Table of contents

Burning is an inevitable process that happens in nature and has a massive impact on life. Technically, burning or combustion emphasizes on the reaction process that consumes oxidizer and fuel to deliver heat and burnt products. Based on the direction of reaction propagation and fuel orientation, burning or combustion is classified in to forward or reverse combustion. Forward combustion is a process which comprises of movement of air and the propagation of ignition zone in the same direction while in reverse combustion, air moves opposite to the direction of the propagation of the ignition zone. Forward combustion escalates rapidly in solid fuels when compared to reverse combustion. The conductivity of the burning solid fuel, convection due to the atmospheric air around and buoyancy effects which takes place due to the difference in air densities plays a major role in the forward combustion process. In this work, thin uniform cross-sectioned solid materials such as matchsticks, candles and incense sticks have been considered as fuel to investigate forward flaming and smoldering. The experiments were carried out in ambient atmospheric conditions. The results based on visualizations suggest that the orientation of the fuel has a greater impact on burning rates and provides us the information on how to burn it in a beneficial way.

Most of the forest fires and building fires are occurring due to the low-temperature flame-less phenomenon called smoldering combustion. The present study is carried for the understanding of fluid flow patterns over the fuel and also fuel under smoldering combustion. The fuel equipped here is a hexagon since most of the modern architectural shapes for buildings, parking lots, hexagon-shaped houses, honeycomb-patterned facades, etc. Regression rates are calculated for the fuel under smoldering. For experimentation, a tabletop wind tunnel is fabricated, and an axial fan is fixed with a speed regulator to investigate the smoldering combustion under the flow and behavior of the fluid flow. The results suggest that the smoldering phenomenon is significantly dependent on the orientation, flow speed and the direction of smoldering with respect to the flow.

Smoke flow visualization is employed to investigate the behavior of a round jet issuing from a straight tube and impinging on a flat plate or bodies mounted on a support. Smoke jet impingement facility is a tool used in aerodynamic research to provide information about the behavior of a round jet of smoke impinging on a model. The smoke impingement jet facility utilizes smoke as seeding for scattering towards visualization. In this study, an impingement jet facility is designed and fabricated that ought to be of low price and straightforward to use. This project aims to offer educators and students an economical means to demonstrate flow impingement over completely different objects employing an easy variety of construction. This work utilizes a smoke generator that can produce good quality smoke and have sufficient density to be visible. The application of this smoke jet impingement jet facility over several test visualization techniques is that it produces high-quality visualizations. The facility has proven to be an economic addition in supporting other research projects and is anticipated to be a valuable 'hands-on' addition to existing aerospace laboratory teaching.

Controlling devices thermally is an important issue to increase the span of any equipment that converts energy and nowadays available latest automation like LED, computer processers and electric battery. Thermoelectric Cooling Technology (TCT) is best option because it has high reliability and also its usage of energy is low for the cooling of devices, which are working on the basis of Peltier effect. TCT have features such as it is not big in size, very light in weight. Also it has no mechanical moving part which results in no or less noise, eco friendly and it does not has any working fluid. This paper presents a comprehensive review of TCT to understand the state of art in the cooling techniques and its applications on heat pipe cooling, sensible air cool warm fan and solar still productivity enhancements. The challenges and opportunities for future research are also highlighted.

Conventional fuels operated an internal combustion engines are the major sources of carbon emissions and it causes environmental degradation. Electric Vehicles (EVs) offers best efficient and cost effective solution for the above said issue, if the battery charging done by renewable energy conversion base routes when compared to conventional based route. EVs are using lithium-ion batteries for energy storage and it have many challenges like low efficiency at low and high temperatures, decline of electrode's life at high temperature and safety concerns related to thermal runaway in lithium-ion batteries are the directly impact on performance, reliability, cost and safety of the vehicle. Overheating caused by electron's movements during chemical reactions during the charging and discharging process in elevated temperatures can lead to fatal destruction of the batteries. Hence an efficient battery thermal management system (BTMS) is one of the most necessary technologies for success of the electric vehicles in the long term. Hence, in this review paper, various types of battery thermal management system along with opportunities for advancement are reviewed. It is concluded that there is a lot of scope for future research in the BTMS for electric vehicles.

One of the important issues in safety analysis of severe accidents in fast reactors is Molten Fuel Coolant Interaction (MFCI). MFCI is the phenomenon in which fragmentation of the molten fuel takes place when it comes in direct contact with liquid sodium coolant. For complete understanding of MFCI, we need to study the solidification of the molten fuel happening along with fragmentation. Solidification / melting of any material initially held at its melting temperature is the classic Stefan's problem. In the case of a severe reactor accident the molten fuel might have a significant amount of decay heat, even though nuclear fission reactions have been stopped by reactor shut down systems. The presence of decay heat in this case, makes the transient Stefan problem more difficult to solve analytically. Here, an investigation of this special case of Stefan's problem with internal heat generation in nuclear materials has been carried out considering a typical droplet size of 4 mm diameter. The numerical heat transfer analysis has been carried out using the commercial software Fluent. The validation of the problem is done with the steady state analytical solution available for the position of phase change front. Parametric studies have been carried out by varying internal heat generation rates and convective heat transfer coefficient at the surface of the droplet. Temperature profiles and liquid fraction are obtained at different instants. Solidification time and final equilibrium temperature are estimated from the results. It is observed that there is significant increase in drop solidification time for heat generation rates (HG) greater than 100 MW/m³ for the drop size of 4 mm. The maximum HG which is tolerated by the droplet without reaching its boiling point is about 6 GW/m³ when the heat transfer coefficient from its surface is fixed at h=56000W/m²K.

In this work the experiment was carried out to investigate the performance, combustion and emissions by changing the number of nozzle holes of the injector such as 3 hole, 4 hole and 5 hole by maintaining the hole diameter as 0.25mm. The experiments are executed on Kirloskar 4-stroke computerized single cylinder air cooled and electrical dynamometer coupled DI diesel engine with diesel, Rubber seed methyl ester and B20 Blend as fuels at 1500 rpm, with the injection timing of 23.4°BTDC with an injection pressure of 240 bar maintained constant throughout the experiment. It is found that 4 hole nozzle gives higher brake thermal efficiency, lower specific fuel consumption, CO, HC, for Diesel, Biodiesel and B20 Blend compared with other two nozzle holes. However the NO_X got increased which is more for all the tested fuels by varying a number of nozzle hole diameter.

Key features of a diesel engine such as the engine effectiveness, release of toxic gas and ignition are examined while using two methyl esters. One of the methyl ester is abstracted from Eucalyptus and the other from Azadirachta Indica. A trans-esterification process is applied on Eucalyptus and Azadirachta Indica oils. The green fuel is used as substitutes in Thermal barrier coating engine (TBC). The use of TBC increases by the temperature of combustion. Experiments carried by EUME, AIME in TBC Diesel engine. The result shows that, the BTE is reduced to the extent of 5.82% and 6.97% and an increase in BSFC to the extent of 11.68% and 12.61% using EUME and AIME in TBC engine in contrast to ordinary diesel propellant used engine. It has also have been observed that the release of NO_X increases in TBC engine also have higher-level release of CO, smoke and HC. The ignition features it has been discovered that the cylinder pressure of EUME and AIME in TBC engine are similar to that of diesel propellant at conventional engine.

A Test Rig consisting of Combustion Ignition engine fuelled with camphor oil blended in the ratio B50 with 5% and 10% DTE (Diethyl ether) is guided for varying loads in the range of 0%, 25%, 50%, 75% and 100%. The result illustrates that increase in concentration camphor oil increases the Brake thermal efficiency with lower values of Brake specific fuel consumption. Also better emissions were recorded with notable decrease in parameters such as CO, HC and increase in the CO2. The introduction of DTE in the blended fuel has been tested and obtained comparable results to that of addition of pure camphor oil in varying proportions, with increases in brake thermal efficiency and limiting in specific fuel consumption values, the effect on the emission characteristics by addition of DTE results in a lower CO, HC, NOX and Smoke with an increase in the CO2. The effective mixing of camphor oil and DTE yield satisfactory result on the performance characteristics at lower load as well as in higher loads.

Maintenance of drains/gutters is huge problem faced by the entire world and especially our country. Manual scavenging is not only unethical but also leads to a high risk of them catching infections or poisoning due to large amounts of waste/chemicals in them. We have provided a motorized drain gutter cleansing mechanism to tackle the modern day gutter jamming issues. Our system is designed in a manner such that fluids are let to flow through but large solid waste like bottles & plastic are caught and accumulated. So human supervision is only needed to take out the segregated waste for further treatment. Hence these gutter cleaning systems can be installed at various points instead of manual labour for entire gutter floors. Since the world is also facing a fossil fuel crisis, the system will be powered with the help of solar energy so as to make it nature friendly and cost effective in the long run. Solar panels, connected to a battery power the system using the radiation received from sunlight. This makes the system not only completely automated but also, environment friendly.

An important factor in the heat exchanger is the enhancement of the heat transfer rate. Heat exchangers succumb to numerous losses resulting because of convection, conduction, and radiation from the experimental set-up which hinders its performance. This project focuses on developing a parallel flow model for the analysis of DOT4 brake fluid considering the numerous energy losses based on experimental results. Various parameters like mass flow rate, inlet temperature on the overall heat transfer rate, and their effects are studied. Basis of the results, parameters are considered for better performance which has been taken into consideration for doing theoretical calculations. This project aims at analyzing the brake fluid both experimentally and theoretically by fabrication of the heat exchanger using mild steel and copper, henceforth experimenting to obtain the analysis of the fluid.

This work investigates the solidification characteristics of deionized water in a stainless steel spherical capsule fitted with rectangular fins immersed in a constant temperature bath. Experiments are carried at three different bath temperatures (-6,-9, and -12°C). Four rectangular fins of size 20.6mm length, width 10.6 mm, and 1mm thick made of copper are fixed on the inner surface of the spherical capsule. Results indicated that fin had a significant reduction in total solidification time. A reduction of 13% in total solidification duration is achieved at -9 and -12°C. However a decrease of 87-90 % in freezing duration is observed while considering 50% of PCM mass at bath temperatures of -6°C,-9°C, and -12°C. It is concluded that fins can be employed in CTES systems at lower bath temperatures to achieve expected energy savings of 9-12% under the partial charging method.

In this experimental work, the Gasoline engine was used to find out the effects of Cu-ZSM5 zeolite coated catalytic convertor on the emission characteristics of iso-butanol additive in ethanol-gasoline blends. The engine was tested under three speeds namely 2000rpm, 3000rpm, and 4000rpm. The volumetric proportion of the fuel samples taken for testing were gasoline (pure gasoline), E10 (90% gasoline, 10%ethanol), IB5 (95% E10, 5% Iso-butanol) and IB10 (90% E10, 10% Iso-butanol). The physiochemical properties of the fuels like heating value, kinematic viscosity, and density were analyzed for these samples as these values influence the emission formation characteristics. The heating value of the samples was decreased with the gasoline concentration in the fuel samples. E10, IB5, and IB10 produced the heating values of 2.34%, 3.13% and 5.05% respectively less than that of the gasoline. However the fuel properties like density, kinematic viscosity tens to increase with the alcohol concentration in the samples. From the performance results, the Brake specific fuel consumption decreased for E10, IB5 and IB10 of about 3.57%, 5.14%, and 7.13% respectively when compared to gasoline. Brake thermal efficiency of the fuel increased to a noticeable level with the addition of the alcohol in gasoline. Initially, the engine was tested by fitting the commercially purchased catalytic converter in the exhaust system and the emissions values were measured with the help of AVL 444 gas analyzer. Then the engine was fitted with the Cu-ZSM5 coated in-house fabricated catalytic convertor and the emission values were measured. At 3000rpm, it has been found that the zeolite coated catalytic convertor reduces HC, CO and NOX emissions by 33%, 9% and 8.3% more than that of the commercial catalytic convertor.

A mathematical model for Solar Flat Plate Collector (SFPC) has been developed to compare the thermal performance between different geometrical profiles of the collector like Flat plate, V-groove absorber plate and with plain and helical strip inserted in the absorber tube. Water, used as working fluid, is passed through the tubes to investigate the thermal performance. Different geometry of the absorber plate and tube are used to increase the heat gain by the collector. The temperatures at inlet and outlet are measured and analysis of collector recovery factor, heat gain, losses like bottom loss, edge loss and efficiency of collector has been done. The comparative study on the thermal performance shows 4% higher collector efficiency for helical strip absorber tube than the other geometric profiles. Also, the results of mathematical analysis closely agree with the experimental results.

In this paper an Organic Rankine cycle is used as waste heat recovery cycle for a 250 x 2 MW thermal power plant. The exhaust flue gas (80 to 130°C) in the thermal power plant is often released into the atmosphere as waste heat. This waste heat can be utilized as a form of heat source for the Organic Rankine Cycle. The treated flue gas form the Flue Gas Desulphurization plant will be fed to the heat exchanger where the heat transfer between the flue gas and the working fluid (e.g.: Ammonia, R245A) will take place. The working fluid will be fed to the (low pressure) turbine where the work done can obtained. After the expansion of the working fluid in the turbine, the working fluid is cooled in the condenser using water. Then this fluid is again sent to the heat exchanger using pump. The flue gas from the heat exchanger after the heat transfer will be then supplied to the stack. The cooling of the condenser water can be done using a cooling tower. As the load varies for the thermal power plant the temperature of the flue gas also changes and hence the turbine shaft output also changes this may result in tripping of the generator. In order to avoid this, a turbine governing system is designed with a step-up gear box and a torque converter. This governing system will keep the generating shaft in motion at constant speed even during low loads and high loads. This cycle will help the thermal power plants to obtain extra power output and will increase the efficiency of the plants.

The increase in surface temperature of solar photovoltaic module due to incident solar radiation has an adverse impact on its performance, reducing its electrical output power and efficiency. Proper cooling can improve the electrical efficiency, and decrease the rate of cell degradation with time, resulting in maximization of life span of photovoltaic modules. Various methods like active cooling, passive cooling and heat pipe cooling are employed to cool the module. In the present work, water passive cooling technique has been used since this method is preferred for small modules and is more efficient because of higher thermal capacity of water. Evaporative cooling is one such technique. Numerical and experimental investigations have been carried out to study the effect of evaporative cooling on the performance of solar photovoltaic module. A two dimensional, steady state, cross flow, heat and mass transfer model has been developed and temperature distribution of air and water across a cooling pad has been studied. An evaporative cooling pad is incorporated at the bottom surface of solar photovoltaic module. Experiments are conducted to evaluate the performance of solar PV module and the results are compared with that of numerical simulation.

Fin and tube heat exchangers are air cooled, cross flow heat exchangers, which have shown broad prospects in places where there is lack of water resources. Research is focused on improving the heat rejection capacity of these exchangers and various enhancement techniques have been studied. Evaporative cooling is one of the techniques employed to improve the performance. Air cooled heat exchangers with evaporative cooling techniques perform better compared to conventional fin and tube heat exchangers. In the present work, a numerical simulation has been developed to investigate heat transfer enhancement in a fin and tube heat exchanger incorporated with evaporative cooling technique. An experimental setup has been built to test the modified heat exchanger and to validate the numerical results. Results indicate 40 to 60% increase in heat duty and effectiveness of enhanced heat exchanger, for cooling water flow rates in the range of 150 to 450 LPH and air flow rate of 300 CFM. Experimental values of heat transfer rate and outlet temperatures of hot water and air are compared with those of numerical simulation and the agreement is generally good.

The utilization of the smoke tunnel for flow visualization of aerodynamics studies needs calibration of the tunnel. This paper aims to describe the characterization of the smoke tunnel using the smoke injection technique. The main phenomenon considered is the wake behaviour occurring at the downstream side of the cylinder. The experiment is conducted by injecting the smoke perpendicular to a circular cylinder placed in the tunnel. The visualized smoke flow lines resemble the streamline patterns which will reveal the wake behaviour. The procedure of smoke based visualization was carried out for various Reynolds numbers and the corresponding physics is described with the limitations of the tunnel.

The recent interests in renewable energy throughout the world has created a need for research in the area of solar technology, specially solar water heating system. A numerical experimental investigation was conducted to develop a model of an active solar water heating system to produce domestic hot water at 90oC using Typical meteorogical year (TMY 2) solar weather condition data of Maiduguri. The numerical experiment was used for simulation and TRNSYS 16 software was also used to determine the hourly thermal performance of the model. The main component of the TRNSYS deck file constructed for this purpose is Type 109, accompanied by other components require for the model. TMY 2 weather data of Maiduguri was processed to obtain the monthly average daily hot water for Maiduguri, and the recommended average day of each months were also used. The weather condition of the month of August was considered for the design. The result of simulation shows that an active solar system collector area of 2.04m2 with inlet flow rate of 120kg/hour for hot water application, tilted at an angle of 12o to the horizontal would be capable of producing daily domestic hot water of 0.1m3 volume to the desired temperature of 90o C. The validation computed by using statistical tool of Nash-Sutcliffe Coefficient Efficiency (NSE) and Root Mean Square Error (RMSE) reveal the system ambient temperature and storage tank temperature of 1.60C,0.82 and 3.60C,0.96 respectively. For the experiment conducted, the model has capacity of predicting the performance of system with 82% and 96% degree of accuracy for that the experiment conducted. The early hours of each months as compared by the collectors showed that the serpentine solar collector has higher thermal performance than the riser-header flat plate collector but after 15:00 hours, Riser-header solar collector performance is better. This means that that riser-header solar collector has higher performance better than serpentine solar collector.

The premixed flames are important with wide range of applications from burners, gas turbine combustor, mixing studies to practical, functional, engineering and scientific research applications. One of the interesting cases of premixed flames is partially premixed flames which has redirected the attention of the scientific community. The partially premixed flames represent incomplete burning, safety hazards, heterogeneous heat and mass transfer. The flame stability of premixed flames comprises an integral role in most of the propulsion applications. For efficient combustion operations and applications, flame stability is mandatory and different approaches have been tried. However, the complexity of the problem has prevented a thorough understanding. One aspect of transitional energy interaction which is yet to be tried is the interaction of magnetic energy with the thermal energy in partially premixed flames. The energy interactions are likely to alter the high energy field supporting flame stabilization and control. The major application includes, enhancement of fundamental understanding and optimization of potential gas turbine combustors, spacecrafts and magnetic nozzles etc. Thorough experimental investigation was carried out utilizing Bunsen burner and designated magnets for varying number of external energy sources, continual variation in interspace distances, and different configurations in repulsion fields. The magnetic effect on the flames is characterized in terms of geometric flame classification viz., Blue flame length (BFL), Yellow flame length (YFL) and Gross flame length (GFL) along with the visible structural changes in the flames. Results clearly state that presence of magnetic energy in the immediate vicinity significantly affect the flame behaviour. With systematic reduction in the separation distance, a non-monotonous drop in the BFL is observed for the cases of 2,3,4 magnet configuration(s) with reduction in the interspace distance.

Acoustics is an integral constituent of most of combustion processes. While combustion advancements have revolutionized human life, acoustics induced combustion also represents a dominant form of instability. Thermo-acoustics, as an intense area of scientific research, covers a wide range of applications viz., industrial (electricity generation), transportation (jet and space propulsion), engineering (system efficiency and operations) and scientific research. The presence of such inept working systems with instability is likely to result in significant loss of resources, infrastructure, property, mankind, nature, with huge amount of money being spent on research activities. Appreciable work has been done before however; the heterogeneous nature of the problem has prevented comprehensive understanding. Thus, the need to investigate and characterize the acoustics imbibed combustion processes to suggest better combustion alternatives/enhance effectiveness and to minimize the resultant hazards. Present work, attempts to resolve the low effectiveness of combustion systems by classification of thermal acoustics and related major hazards. A simple experimental setup was upraised comprising of butane cylinder with nozzle and systematic experimentation was carried out to explore the phenomenon of energy transition in combustion with acoustics. The exploration was carried out for varying fuel mass flow rates, L/D ratios, material of tubes, interspace distance and counter acoustics impingement. The results were observed with acoustics measurement, along with type and structure of flames. The work is primarily motivated by the need to have technologically enhanced combustion understanding and for fire safety applications. The results exhibit that presence of external enclosures have significant effect on thermoacoustics and with coupled redundancy effect, a special pattern noted was both the controlling parameters results in reduction in maximum acoustics rise and increase in maximum drop levels this contributing significantly to enhancement of system efficiency. The results can be of pertinent significance for the testing, validation of conventional systems and designing of the efficient and safer futuristic propulsive systems.

Light weight – thermal insulation concrete has a growing demand in energy efficient building. It can be used in places where there is a requirement for thermal insulation in the form of tiles and weathering coarse for roof as well as in places where there is a need for thermal lining. For the preparation of light weight – thermal insulation concrete, a cement replacement mix consisting of Silica fume, Metakaolin, Egg shell powder, Alccofine were used along with different particle sizes of Cenospheres as a fine aggregate replacement. The test concrete samples were tested for their physical and mechanical parameters like compressive strength and its thermal conductivity were investigated. The light weight – thermal insulation concrete has a reliable compressive strength and a satisfactory thermal insulation property.

Presently, the advancements in the field of rockets and rocket propulsion has been done to such an extent where the mission success rate is surely more than its failure. This has also led to a need for much better efficient materials (propellants) that form a major part of the rockets. The project deals with the combustion and the propulsion characteristics of the rockets. In combustion part, the experiments are conducted on normal paraffin wax candle, coated with different energetic materials in order to calculate the burn rate with the help of videography. This addition of energetic materials enhances the regression rate of candle. The propulsive characteristics, like the specific impulse and characteristic velocity, are studied through simulations carried on the NASA-CEA software in which a base composite propellant (AP/HTPB/Al) is present along with highly energetic materials. The energetic materials considered here are either fuel, binder or oxidiser which helps us to study the variance in the specific impulse and the characteristic velocity. The key parameters here are pressure, temperature, the oxidiser to fuel ratio and the composition of the material. One of the novelties of this study is to create a relation between the combustive and propulsive characteristics as there is not existing correlation between them. Other importance of this study is the concept of Hybridisation put forth to simplify the addition of material in the propellant. This concept has been studied extensively come up with a better hybrid propellant that can be used to improve the efficiency of the rocket.

Scholars and scientists have been trying to find ways to control and alleviate the consequences of concurrent fires such as forest fires, building fires and various space fires but no compelling solutions have been concluded from their studies so far. The basic cause of these kind of fires concerns with the unstable nature of the flames and marked unpredictability associated with it. For example, the breakout of one of the deadliest wildfires in California in 2018 and the Amazon fire of 2019 shows us the gravity of the situation and also the immediate requirement to control such mishaps to save lives and properties valuable to us. This led us to make an attempt to study the behavior of such flames – an experimental setup with rather ideal conditions was devised and a thorough home-scale study was carried out. This present study mainly concerns with the study of fire propagation phenomena and the vitality of fire control in our daily life. This study involves the review of the varying regression rates and fire spread rates of flames as observed in matchsticks when spaced in both linear and non-linear orientation for different configurations. The behavioral instability of the flames will give us an insight into the heterogeneous fire propagation phenomenon and its control. An insight into the heterogeneous fire propagation is expected for essential fire safety and, on its basis, an algorithm for the same is to be formulated. With this knowledge along with the existing information, it might help us quantify the extent of fire propagation by means of a non-dimensional entity which might as well give us some possible solution to the reduction of such kind of fires in forests, buildings, large scale fires in industries, space propulsion systems.

The objective of this paper is to study the effect of spacing ratio on the wake dynamics in an inline arrangement of four cylinders. Different spacing ratios, defined as ratio of distance between center of two cylinders and diameter of cylinder, are considered while. Reynolds number (Re) kept constant. At the chosen Re, far wake is expected to transition to turbulence, and hence κ-ω SST turbulence model is used for turbulence closure. The flow field and associated surface properties such as drag and lift force are strong function of spacing ratio. In the numerical solutions it is observed that, two counter rotating vortices are formed in the gap between the cylinders. These two vortices found to move towards downstream as the spacing ratio is increased. Also, the size of the vortices found increased. The two counter rotating vortices appears symmetric near cylinders, and hence lift coefficient observed to be very low for the first three cylinders. Lift coefficient observed on fourth cylinder found to one order of magnitude higher. The drag coefficient for all cylinders found to be positive except for the second cylinder which has negative drag for all spacing ratios.

This paper deals with evaluation of engine performance using preheated biofuel utilizing the waste heat generated from exhaust gases. The performance characteristics and emission parameters are compared with the trans-esterified biodiesel. It is understood that the preheated biofuel run in the engine was capable of producing appreciable brake thermal efficiency as that of biodiesel run CI engine. This effort simultaneously reduced the heat loss to the environment, thereby improving the exergy of the system. The neem biofuel was heated to 70°C and 80°C before injection by the exhaust gases. HC and CO emissions were reduced by 22.3% and 19.01% respectively. NOx emissions suffered an increase of 18.6%. The improvement in BTE was 5.5% compared to non-heated biofuel.

The effects of Momentum Injection can play a vital role in increasing the efficiency of an aerofoil by increasing its lift and delaying the stall angle. Most of the studies regarding this concept analyzed the effects of momentum injection for higher velocity ratios (cylinder tangential velocity to free stream velocity) only. Almost no or less studies analyzed this effect for lower velocity ratios which created a research gap in this field. In this paper, a rotating cylinder is placed at the leading edge of an asymmetric aerofoil NACA 23018 and the aerodynamic performance with and without a rotating cylinder was studied for lower velocity ratios (<0.2). The experimental analysis was carried out for two Reynolds numbers (Re): 2 × 10⁵ and 2.5 × 10⁵ corresponding to two free stream velocities: 20 m/s and 25 m/s, respectively, for six different angles of attack (−5°, 0°, 5°, 10°, 15° and 20°). The experimental analysis showed that incorporating a leading-edge rotating cylinder increased the maximum lift coefficient by around 24% and delayed the stall angle by around 20%.

Catalytic converters are commonly used for automotive engines to reduce regulatory emissions. Catalysts used in commercial converters are expensive and they work in particular temperature ranges. To overcome those problems, Zeolite 5A powder is chosen and used as a catalytic material in the catalytic converter to reduce the emissions from the Compression Ignition (CI engine). Zeolite 5A was molded into solid by adding distilled water and carboxymethyl cellulose as binder material. The prepared solid mold was used as catalytic material in the exhaust gas after-treatment system. The waste plastics were pyrolyzed into oil and blended equivalently with diesel (50:50 ratios) for this investigation. The performance and emission readings were taken by varying the engine loads (0, 1.32, 2.6, 3.9 and 5.2 kW) in the single-cylinder 5.2 kW CI engine. The NO and HC emission were reduced by 37% and 33% respectively at the full load condition.

The need to obey with increasingly stringent emission regulations has amplified the importance of after treatment devices, and therefore, reliable tools need to be developed for the evolution of better aftertreatment devices. Even though the upcoming regulations paved the way for improved combustion engines, their high carbon monoxide and hydrocarbon emissions increased the load on catalytic converters. Numerical modeling is one such tool which is extremely useful in providing the basic information which helps in designing the reactor, understanding its operation, and predicting the performance. In this context, the utmost aim of the numerical modeling is to simulate the driving cycle where inlet conditions to the catalytic converter vary with respect to time. Such a simulation must include the calculations of transient temperature-field of the monolith substrate and converter-out mass emissions. In this paper, a one-dimensional mathematical modeling of an oxidation catalyst has been implemented to simulate a hot start New European Drive Cycle (NEDC). The transient engine data was taken from the literature, and the measured instantaneous traces at the outlet of the catalyst were compared with the model predictions. This model has been developed to investigate the CO conversion performance of the catalyst. The comparison between model predictions and experiments has shown a satisfactory agreement in terms of both substrate temperature and CO emission at the catalyst outlet, confirming the effectiveness of the methodology applied. The reliability of the 1-D model was also proved with the probability density function of the conversion efficiency.

Heat exchangers are one of the most heavily studied devices and extensive work has been performed over the years to increase their effectiveness. The present work investigates the heat transfer characteristics of an APHE (annular porous heat exchanger) in terms of different parameters. A modified design for the APHE is proposed, which resembles a conventional double pipe heat exchanger, with the annular portion of the outer pipe filled with a specific type of porous medium in order to intensify the heat transfer process. Commercial CFD package ANSYS Fluent has been utilized to investigate the performance of the proposed design numerically. Introduction of porous medium induces an increase in pressure loss which is undesirable; hence, a trade-off is present between hydrodynamic and thermodynamic performance. In the present work different inlet parameters have been modified such as different values of porosity (70% to 90%), different inlet velocities of hot fluid (1 m/s to 9 m/s), different inlet velocities of cold fluid (5 mm/s to 25 mm/s), and different inlet temperature of hot fluid (400 K to 480K), and their effects on the outlet parameters have been studied. The change in heat transfer has been presented quantitatively along with other significant parameters such as mass flow rate, pressure drop and hot gas outlet temperature. These results have been compared with the values for conventional heat exchangers in order to establish the effectiveness of APHE.

Investigation of the combustion process in engines for improved fuel economy and emissions is best done by combining experiments and simulations. In the present work both experiments and simulations are conducted considering a naturally aspirated common-rail direct-injection (CRDI) diesel engine. The CFD model is developed based on experiments conducted at two operating points, representing to a 0.9 l, two-cylinder, diesel engine. The developed CFD model is then used to study the effects of different in-cylinder strategies attempted at reducing emissions, without compromising on performance. Previous researches conducted on diesel engine CFD simulations are generally based on large-bore large-capacity single-cylinder engines, and mostly investigated a single operating point. The present study investigates the effects of combustion chamber geometry, injection timing, multiple injections as well as EGR, individually as well as in combination, on NOx and soot emissions, at two different operating points in a small naturally aspirated CRDI diesel engine.

In-cylinder fluid motion has a substantial impact on air-fuel mixture formation, combustion process and emission formation. In the present paper, a simulation study of the in-cylinder fluid flow is performed using a computational fluid dynamic (CFD) model of a port-fuel-injection (PFI) engine (volume: 110 cc). First, a 1-D model is developed, and validated with the cylinder pressure traces acquired in an optical engine experimentally. The model provided the boundary conditions for multi-dimensional numerical simulations. The predicted velocity fields from CFD are then compared with the measured data obtained using particle image velocimetry (PIV) at various crank angle positions with low throttle opening condition. A good relevance is observed on comparing numerically estimated results with experimental results.

There have been many insects having a tandem wing configuration that gives them a major advantage for maneuvering with various desirable speed, such as dragonflies and butterflies, but subsequently have been used for a wider range of applications. So, it is well known that the tandem airfoil arrangement will have better aerodynamic characteristics than those of the single airfoil arrangement. The present work aims at numerically predicting the aerodynamic characteristics of the single airfoil and tandem airfoil arrangements of the Wortmann FX 63-137 airfoil profile at a Reynolds number of 0.5 x 10⁶. The numerical simulations are performed using commercial CFD software, ANSYS-Fluent. Turbulent flows are modeled using the k-ω RANS model with a second-order upwind scheme. The pressure-velocity coupling is done through the SIMPLE algorithm. In the tandem arrangement, airfoils are positively staggered in the flow direction with variable gaps ranging from 0.1m to 0.7m with an increment of 0.2m and the perpendicular distance between the leading edges of two airfoils is fixed at 0.3 m and simulations are performed for a various angle of attacks with a range of 0 to ± 14°. The aerodynamic characteristics of the single and tandem arrangements of the same airfoil are compared and the effect of wake from the primary airfoil on a secondary airfoil at different angles of attack is also studied for the same conditions.

In modern world, energy is a blessing, but its production is a problem with many human and economic ramifications. Comparing with others, solar and wind energies are much popular but have their own problems, primarily cost. Some of experiments are at MIT's Media Laboratory are happening with cheap alternative energy sources. Wind energy is more efficient according to research, than solar energy. Mathematically it is proven, with the help of a 3 square meter turbine where velocity of wind is 36 km per hour and with 30% of total efficiency about 300 watt can be obtained. The main contents of this project and thesis include the design, construction and calculating the performance of aerofoil shaped turbine blade. To construct the aero foil shaped turbine three blades and a wood-hub are used. A shaft is fitted with hub with 5 cm diameter; a metallic gear is there for supporting the other end. In addition, gearing system is there to make the speed of output shaft are more high. A24 volt generator is also connected to the output shaft. The primary output was 6 watt &amp; can apply this output power in various purposes like to run energy saving lamp, to charge mobile battery &amp; other charge storage battery. A model has been used for simulation since the site of the actual turbine was not feasible for collecting effective data. The model was tested at different wind speeds and rpm of the rotor with respect to the amount of electricity produced.

The present work focuses on the green synthesis of nanoparticles by using bael leaves. It is a naturally occurring material for synthesizing nano additives. Characterization studies such as particle size analyzer and UV spectroscopy are been used to examine the inherent properties of bale leaf to be used as a nano material. The particle size study confirms that the produced nanoparticle has an average particle size of 50 nm with 200 nm diameter. The study by UV spectroscopy confirms that the nano crystal has a BCC structure with a peak absorption of 9.82 a.u. On the other hand, the physical and chemical properties of nano particle doped with B20 such as kinematic viscosity, calorific value, density and flash point are measured and compared with ASTM standard is presented in this paper.

Nowadays there is an increase in the usage of non-renewable products to produce the energy required to sustain in day to day life, which results in the generation of harmful emissions such as greenhouse gases, in turn, leads to an increase in earth's surface temperature and depletion of the ozone layer. On the other hand, the generation of usable energy requires fossil fuels to satisfy the thermal input. So switching to renewable energy for the thermal input for fossil fuels saves the environment for further damage, mainly solar energy which is abundantly available and free of cost. Hence creating much more interest in researchers to establish and enhance the performance of solar energy coupled reactor. By implementing solar energy as the input for the reactor there will be a decrease in the consumption of fossil fuels to produce heat energy. In this present study solar concentrated power is used as an input fuel supply to the reactor process where the dish type concentrator used of diameter 1.4m and has a focal length of 0.28m which is focused towards the preferred conical shape reactor because of the effective flux distribution inside the reactor than the other shapes. The reactor volume of 13.9m³ is fixed at the focal distance where the receiver absorbs more amount of radiation from the concentrator, leads to an increase in the temperature inside the reactor and the specimen inside the reactor will generate gases. by using the coal ash as a catalyst there is a temperature increase of 10%. That is without any catalyst the reactor inside temperature is 100°C and with coal ash as catalyst 110°C.

Global warming is one of the major concerns of the modernera. It is caused bythe surplus presence ofgases like CO₂, CH₄, NO_x, and SF6, which can entrap the sun's warmth within our atmosphere leading to the greenhouse effect. Past surveys showthat the atmospheric CO₂levels, which has been on a steady rise due to burning of fossil fuels as well as incomplete combustion in IC engines, is the key factor to the climate change problem the world is facing right now. One of the ways to reduce thisCO₂crisis is to capture carbon emissions at the source itself. This paper deals with a process to reduce CO₂ levels by employing a combination of zeolite, activated carbon and monoethanolamine (MEA) with the help of Aluminium fine wire mesh. The properties of zeolite 5A have been adapted in capturing the CO₂ due to their high micro porous structure and MEA due to its high CO₂ absorbing characteristics. A slurry is prepared and the aluminium wire mesh is dipped in it, dried and is later kept in the exhaust pipe for the results. A comparison of the carbon emission with and without mesh is tabulated and presented with discussions.

Increase in energy demand, stringent emission norms and depletion of oil resources has led to find alternative fuels that are compatible with internal combustion engines. This paper presents the study of performance and emission characteristics of CI engine fuelled with pine oil and cotton seed oil blended in the blending ratio 70:30, 50:50 and 30:70 respectively. The experiment was carried out in four stroke single cylinder diesel engine by varying the load from 0% to 80%. The result shows the blend of cotton oil and pine oil used as a fuel has increased the brake thermal efficiency with reduction in exhaust gas temperature and specific fuel consumption. By using different blends, it shows the reduction in emission parameters such as CO, CO₂, NO_X and smoke and yields satisfactory results.

Numerical study was conducted on the LOX-RP1 engine bell nozzle to replace the dual bell nozzle for determining the optimum expansion ratio and greater thrust at sea level. Here base nozzle is a conventional Rao's TIC nozzle, where throat radius, exit radius, inflection angle and exit angles are 138mm, 826mm, 33° and 8° respectively. The total length of dual bell nozzle and existing bell nozzle are kept same. Numerical analyses were carried out in ANSYS FLUENT software on different dual bell nozzle geometry to evaluate the thrust and expansion ratio. Numerical analysis is performed by two dimensional, axi-symmetric, steady state, pressure based solver with SST k-ω turbulence model at different ambient pressures to recreate the patterns of flow in the nozzle at different nozzle pressure ratio (NPR) and expansion ratio. The profile has made by commercial software SOLID WORKS^TM. Numerical simulations and flow separation locations are validated with the experimental data published earlier. It is observed that with area ratio 150 and inflection angle 15° the thrust has increased by 5.46% at sea level and around 10.5% in vacuum, where the increase in exit radius and mass is only 96 mm and 6 kg respectively.

The current study aims to analyze the solidification and melting characteristics of nanofluid phase change material (NFPCM) for building cooling applications. The NFPCM were prepared by using graphene nanoplatelets (GNP) in different concentrations (0.2, 0.4 & 0.6 Wt. %) and DI water as base PCM. The NFPCM was prepared using two step methods and stability of the NFPCM was analyzed using visual sedimentation method. The experimentation was conducted in -12 °C and -9 °C surrounding bath temperatures. The Sub-cooling was eliminated completely for the addition of SDBS and GNP in maximum concentration. The experimental results showed that the 10 % and 8.5 % reduction in solidification time for 0.6 wt. % GNP in base PCM for the surrounding bath temperature of -12 °C and -9 °C respectively. Also, the DSC analysis was conducted for the heating rate of 5 K/min and the reduction of enthalpy during heating and cooling was noticed 14 % and 11 % respectively. It is observed that the reduction of overall solidification time of the NFPCM will have the predominant effect in the chiller operation time.

The efficiency and power output of the solar PV panel decreases with an increase in temperature. The efficiency of a monocrystalline photovoltaic panel decreases around 0.3% for every degree rise in temperature after 30°C. By using different techniques we can reduce temperature. A heat sink made up of aluminium plate with fins attached to the PV panel which enhances heat rejection. The analysis of the system was done in computational fluid dynamics (CFD). The static and transient analysis was done and an optimal heat sink was designed. The silicon plate which is designed to simulate the PV panel was maintained at a temperature of 60°C for the analysis. It was found that the optimal fins of heat sink have 1.5 mm thickness and each of 40 mm height and 30 mm spacing between the fins and the natural air flow is maintained through the fins which is parallel to fins. There is a reduction in temperature of panel by 4°C in static conditions by natural convection.

Fresnel lens reduces the amount of material required compared to a conventional lens. By employing this technology to two of the ubiquitous resources available almost everywhere – sunlight and brine water - we produce steam. Focused sunlight by sun tracking was used to boil water from a copper tube while a spiral piping is used as a condenser. With LDR sensors and a high torque servo motor, the solar irradiance was maximised. This was done using 'Adruino Uno' micro controller coded to use real time data obtained from the LDR sensors. The apparatus was tested on sunny, partially cloudy and cloudy days in manually set to North – South direction manually. The amount of water distilled was proportional to the solar irradiance and were highest, mediocre and lowest respectively for three sample days of varying solar albedo. Though black paint on copper boiler helped to increase distilled water productivity, loss in heat from the system was evident. An average of 1.6 litres of water was produced per day by the system with boiler volume 3.18 litres and rectangular Fresnel lens of size 345 x 345 mm. Heat loss from system may be further controlled by larger aperture lens and selective insulation of copper duct. Addition of baffle for heating and fins at condenser may increase heat transfer rate.

In this paper, we have conducted a study in a 2.2 kW variable speed SI engine coupled with electrical loading, whose main objective is to reduce the NO_x emissions coming out of the engine. To achieve this outcome, we have opted for the EGR technique. We have opted for this technique because firstly it is a proven technique that has been successfully implemented in CI engine and secondly as it reduces the peak engine temperature leading to increased engine life. EGR is implemented by using EGR manifold which replaces the regular intake manifold. Also, a flow control valve is used to control the percentage flow of exhaust gases. From this study, we can conclude Cold EGR is effective in reducing NO_x but lowers the efficiency. Additionally, a reduction in CO₂ percentage is also observed at the cost of the increase in HC.

A three dimensional computational study of the thermo-hydraulic characteristic of the fin-tube heat-exchanger with the upward rectangular winglets vortex and the elliptical tube of various elliptical ratios are analyzed in the study. The ratios are b/a=1.0, b/a=0.333 and b/a=0.307. The numerical studies is performed with the Reynolds no (R_e,) within the range of 500-3000.The temperature contour and streamline patterns were presented to explain the reason for the pressure drop and heat transfer and to analyze the flow in different arrangement. It is demonstrated that the upward rectangular winglets vortex and the elliptical tube design in case of lesser pressure loss and less separate flow which is preferred in the heat-exchanger application in order to save energy.

In the World, perhaps the most significant issue as far as people understood, non-renewable sources would be extinguished. Apart from that, non-renewable energy sources are one of the critical factors for pollution, global warming. To address such issues, it is vital to shift to sustainable power sources, for example - sunlight, wind, etc. are essential in the present century. To examine the available solar tracking methods and algorithm, which have better accuracy and high output power efficiency. Multiple databases were searched for English literature and limiting to last ten years. The keywords selected for the search were a combination of the solar tracking algorithm, PLC, maximum power point tracking system, and solar tracking. The search results suggested that research on solar tracking is required to increase the generation of electricity. Many International research institutions conducted research related to solar tracking systems and tracking algorithms. The solar tracking is done, by utilizing mechanical sensors to maintain the PV module perpendicular to the sun's irradiation. Proficient solar tracking methods are investigated by directing various analyses. The usage of renewable energy sources is lacking. Also, by designing an optimized solar tracking system for the generation of better output power is recommended.

This paper reveals the numerical investigation of the helical capillary tube. The study is carried out for an adiabatic, homogenous capillary tube with the R744 refrigerant. The basic principles of conservation of mass, momentum, and energy are used to develop the mathematical model. The results of the present coiled capillary tube model are verified with previously published test results. The refrigerant properties of R744 are employed from CO2PROP. The influence of various geometric parameters of the capillary tube-like tube diameter, roughness, and coil diameter on the performance of the tube been computed. The consequence of the tube diameter on the tube performance is larger than other geometric parameters. As the tube diameter increase by 18%, the mass flow rate increase by nearly 55%. Similarly, as an increment in the coil diameter took place by 10%, the mass flow rate increase by 5%. The negligible change is observed owing to the change in surface roughness. While the surface roughness increases by 18%, the mass increases by 1%. Moreover, the influence of various operating factors is evaluated. A significant variation in the tube and system performance is seen owing to the change in gas cooler temperature. As the gas cooler temperature rises by 5%, the drop in mass flow rate is about 18%. Comparatively, less effect is recorded due to an evaporator temperature. As the evaporator temperature rises by 15%, the mass flow decreases by nearly 11%. The considerable impact is perceived owing to the change in pressure of the gas cooler. As the gas cooler pressure increases by 4%, the mass flow rate increases by nearly 7%. Similarly, the influence of operating and geometric parameters on the coefficient of performance and cooling capacity of the transcritical R744 system is evaluated. For optimum performance of the R744 cycle, the selection of proper gas cooler temperature and gas cooler pressure is a key factor. This work is useful to design the helical capillary tube with R744 refrigerant.

The transonic flow field over a launch vehicle is complicated due to presence of a normal shockwave on the heat shield. To predict the aerodynamic loads, the shockwave position needs to be predicted accurately. The present work aims at predicting the flow field over a typical launch vehicle at an angle of attack (AOA), and analyzing the effect of AOA on flow field, shockwave position and aerodynamic and moment coefficients. The launch vehicle considered here is a long slender body with spherical nose followed by the conical, cylindrical and boat-tail portions. Simulations are performed at a Mach number of 0.95with AOA of 0°, 2°, and 4°. Commercial Computational Fluid Dynamics package ANSYS Fluent is used for simulations. Density-based algorithm is used to obtain the steady state solutions with explicit time stepping.κ-ω SST turbulence model is used to close the turbulent stresses terms. The surface pressure distribution in axial direction is analyzed to understand the effect of AOA on the aerodynamic and moment coefficients. It is observed that as AOA increases, the normal shockwave moves towards nose. The drag coefficient and pitching moment coefficients are found to increase with increase of AOA.

Recent days the availability of a conventional source of energies are limited dueto overexploitation of resources. This can be prevented by replacing the conventional source of energy to renewable energy which is believed to be the future. In renewable energy, there are many types among which solar energy is the best and most effective as it is abundant, freely available, and it has a lot of versatile applications. The main objective of the research is to study the suitability of antenna dish for thermal application by optimizing the various parameters to achieve maximum thermal collector efficiency. Considerable enhancement in the performance of the solar dish collector was observed by altering various absorbents on the receiver.

An unsteady thermal boundary layer analysis over a heat source (flat plate) has revealed that first order temperature change in source and core flow temperatures affects the time average or RMS value of h'S. It also emphasize that 1st order changes are important. Analysis also indicates that a phase difference between pressure and temperature exists at the source in order to increase the RMS value of h'S. Value of h'S is directly proportional to the tan/sine of the above phase difference, This implies that entropy oscillations must exist at the heat source. The purpose of this paper is to compare the result of 2nd order analysis previously done, with the 1st order study carried out in this paper. In second order analysis time average of h"S depends upon 2nd order change due to 1st order effects. Finally, existence of phase difference between pressure and temperature, thus having entropy oscillations are evident, comparison implies although there is similarity between 1st order and 2nd order results but first order effects are more important than 2nd order effects.

The present escalating demand for the hydrocarbon fuel and its lack of availability move the automotive industries and the oil companies to urge the search for alternative resources and feedstocks to emerge a fuel for transportation to keep going. This paper deals with the examination of properties of the Tamarind seed Biodiesel and the petroleum diesel fuel with biodiesel oils of significant feedstocks. The raw oil extracted from Tamarind Seed was trans-esterified with methanol in the presence of potassium hydroxide to obtain biodiesel. The oil yield was 35%. The study was to figure out the variation in the physicochemical properties of the biodiesel for their progressive blend percentages with the petroleum diesel. The blends investigated were B20, B40, B60 and B80. The vital physicochemical properties of the biodiesel evaluated were a flashpoint, fire point, kinematic viscosity, and the calorific value. Importantly, the calorific value of B100 is 45.83 MJ/Kg and diesel is 45.49 MJ/Kg. The increasing biodiesel concentrations show, the kinematic viscosity of the blended fuel decreases to 2.4 cSt at B80 from 2.63 cSt for Diesel, which is 13%. The flash and fire point value of the diesel fuel which is 37.4 and 56.7°C, was incremented with the higher concentrations of biodiesel as 41.2°C and 57.7°C at B80.

With the ever-increasing pollution rate, we have considered the need to control automobile emissions which are responsible for global warming. In this paper, we aim to propose a cost effective and sustainable design prototype of a catalytic converter. Design was done by considering some of the problems in existing catalytic converter like back pressure, cold start emissions and cost. The new design of the Catalytic converter includes a new catalyst i.e. Lanthanum Strontium Manganite (LSM) with a piecewise placement approach and a hexagonal random cell shape which is in contrast with the existing platinum-palladium catalyst and honeycomb structure. Analysis of the design of Catalytic converter was done which included the ANSYS CFD and mode shape analysis. The cold start emissions were reduced by using a method to pre - heat the air at the input of the converter shell using Arduino controlled heat plug. The testing of the converter assembly was done on a single cylinder Briggs & Stratton Engine and results were taken using Exhaust Gas Analyser which gave us the emission outputs with and without catalytic converter at idling and full rpm of the engine.

The objective of this paper is to study the effect of spacing ratio on the wake dynamics in an in-line square array of four cylinders. Two dimensional incompressible CFD simulations are done with commercial CFD software Ansys-Fluent. Diameter of cylinder is 0.01 m, and the four cylinders have identical diameter. The spacing ratios considered are 1.5, 2.0, 2.5 and 3.0, where spacing ratio is defined as ratio of distance between center of two cylinders and diameter of cylinder. Simulations are performed at a Reynolds number (Re) of 200. Water is considered as fluid medium, and velocity of water corresponding to Re of 200 is 0.0178 m/s. SIMPLE algorithm is used to solve incompressible Navier-Stokes equations, and second order accuracy is used for spatial discretization. At the chosen Re, far wake is expected to transition to turbulence, and hence κ-ω SST turbulence model is used for turbulence closure. The flow field and associated surface properties such as drag and lift force are strong function of spacing ratio. The impingement of shear layers of upstream cylinders onto to the downstream cylinders is strongly influenced by spacing ratio. The impingement and resulting flow interaction leads to asymmetry in the surface pressure distribution. This leads to generation of lift force on the cylinders. For spacing ratio of 1.5 and 2.0, the top row cylinders have positive lift coefficient, and bottom row cylinders have negative lift coefficient. For spacing ratio of 2.5 upstream cylinders have positive lift coefficient, and downstream cylinders have negative lift coefficient. All four cylinders have positive lift coefficient for spacing ratio of 3.0. Drag coefficient found to be positive for all cylinders and for all spacing ratios.

The extremely high demand for energy and increased demand for fossil fuels has led us to shift our concentration towards new and renewable sources of energy, which are seemingly unlimited sources. They are zero-carbon emitting, thus eco-friendly for the environment. Several issues have been addressed before regarding different topologies for standalone and grid connected inverters with and without microcontroller circuits. Some of them have addressed the introduction of multilevel inverter input using buck boost converters for improving the efficiencies of the output circuit. This paper enlightens the design of single stage photovoltaic inverter which is needed to run AC appliances as loads, which are mostly used as consumable purposes. The design implements MOSFETs as switching devices, which have considerably high switching frequency of 40 KHz, power diodes, inductors, capacitors, solar panel and a battery. The proposed inverter converts the DC output of the PV module into AC directly while maintaining the stability in the output voltage. PSIM software has been used for inverter design. The improved efficiency resulting in 75-90% is due to the minimized voltage drop over the inductor. High frequency operation of the MOSFET switch enables minimized switching losses.

An Oxygen Generator is developed to interface with Home Air Conditioner that serves for Home Oxygen Therapy & it is controlled by a Microcontroller which is connected to an IoT app through which users can monitor and control the whole system. Oxygen levels are to be maintained as per OSHA cited acceptable levels. For generating oxygen we are using Pressure Swing Adsorption Technique with two bed molecular sieve columns with Zeolite filled inside in it which acts as a Filtering component of Nitrogen. When a Pressurized air is passed through the Zeolite it filters out Nitrogen (due to its chemical nature Nitrogen molecules gets trapped inside its pores) and allows rest of the Air components pass through it so that we can get oxygen enriched air at the outlet and it is given to home.

This study aims to investigate the solidification characteristics of water based nanofluid NFPCM (Nanofluid phase change material) with an aim to form an efficient CTES (Cool Thermal Energy Storage) system. Here we have taken base PCM as deionized water and Graphene is taken as nanoparticle because of its property of high thermal conductivity. The PCM was prepared by adding surfactant (0.2wt%) which is used to reduce the surface tension of the solution and then various concentration of graphene nanoparticle are added i.e. 0.2wt% and 0.4wt%, and the effect in solidification time and reduction of sub cooling is seen and studied. The enhanced heat transfer rate of NFPCM without sub cooling is advantageous for many CTES applications. So, finally it is constructed from experimental results that by embedding this technology with chiller systems which is used to cool large spaces can help us to conquer our motive to save energy and provide effective and efficient cooling.

A shell and tube device is deployed for the applications such as oil refinery processes, chemical processes and high pressure technologies. The hot fluid flows to the tubes in the heat exchanger, and the cool fluid moves through the shell section. Hence, heat is transferred from the tube section to the shell section of the heat exchanger. This article is deals with the modelling and analysis of mini shell and tube heat exchanger (MSTHE) for low temperature applications which is less than 250°C. The design of the heat exchanger is made with nine tubes which are of 6 mm diameter and shell of 41 mm diameter. As conventional design does not result in the internal heat transfer, computational fluid dynamics scheme is adopted to design the modified heat exchanger by adopting the conditions such as velocity of tube fluid and pressure drop. The modelling of MSTHE is done by Pro/E whereas CFD analysis is done with ANSYS. The contour obtained from the analysis proves that the MSTHE is applicable for the temperature less than 250°C and have the potential to transfer heat effectively.

The present study is an experimental investigation of compressible jet flow from a pipe with a hexagonal cross-section. The pipe is fixed to a settling chamber which is supplied with compressed air by a storage tank via a pressure regulator. The experimental methodology includes the measurement of centreline variation of stagnation pressure and the visualization of shock structures. The results from the present pipe shape considered for the present study will be compared with the results of jet flow experiments from a circular pipe. The diameter of the circular pipe is taken as 15mm and the same is fixed for the hexagonal pipe. The L/D ratio of the pipe is chosen as 5. The nozzle pressure ratio will be varied according to the source available and the measurements will be taken via a Pitot tube connected to a Pressure Scanner. The positioning is controlled by a traverse mechanism which can move in axial and transverse directions. The results obtained will be discussed in detail with the help of relevant literature.

Jet flow through pipes/nozzles has been successfully applied in various fields and has a further wide scope in fields of Flow Control and Acoustic Suppression. In the past few decades, jet flow through pipes and nozzles have been widely exploited, researchers found that non-Circular Pipes possess some unique properties, with which the need for research in this field increased. This work presents the properties of jet flow from a Square Pipe (L/D=5) over the Circular ones. Experiments are done in Compressible flow conditions using 3-D fabricated Pipes of Circular and Square cross sections. The cross sectional area of the pipe exit is maintained same for both the Pipes to facilitate comparison of results. This study highlights the advantages of Square Pipes over the conventional ones via pressure measurements.

This paper addresses the various design parameters of an atmospheric boundary layer (ABL) wind tunnel and also explains the approach taken to construct the various parts of the wind tunnel. The paper tries to explain the different design stages in the tunnel construction and methods to replicate turbulent boundary layer profiles in it. Rather than using conventional material like wood, a new approach of using aluminum profiles for the basic framework has been used. These profiles have proven advantageous to tweak the dimensions of the tunnel to obtain varying flow profiles.

Studies on turbulent inlet flows have a wide variety of applications, Backward Facing Step (BFS) facilitates this study. The phenomena of flow separation occur due to an abrupt change in geometry, causing the creation of a re-circulation zone and a flow reattachment point. The present numerical study focuses on the assessment of different turbulence models. The flow velocity is in the turbulent region characterized by the Re=7000. Steady State Reynolds Averaged Navier Stokes equations are solved along with various turbulence models using OpenFOAM® which is an open-source Computational Continuum Mechanics toolbox for conducting numerical simulations. The simulated data is processed using Paraview and the assessment of the turbulence models is performed via quantitative (reattachment length) and qualitative (Line Integral Convolution visualizations) methods.

The purpose of the present work is to study the solidification behaviour of a di-water based PCM for cold energy management applications. Thickening agents such as agar, gelatin and cornstarch are examined at various mass fractions. The experiment is carried out in a low temperature bath of -7°C inside which the PCM sample is kept spherically encapsulated for uniform distribution. The behaviour and effect of addition of the nucleating agents are compared. The analysis showed that the subcooling of di-water was substantially reduced and its crystallisation occurs at a faster rate. It is concluded that faster crystallisation and reduction in subcooling can help increase the efficiency of a cool thermal energy system and can be applied to any commercial system in the society to help alleviate the electrical load.

The fluid flow and heat transfer characteristics for a laminar flow in a two-dimensional grooved microchannel has been numerically investigated. A suitable range of parameters such as Reynolds numbers, volume fraction, and groove offset are studied. The characteristics are investigated for various offsets in the grooved microchannel. The results specify an increase in heat transfer performance with increase in volume fraction, Reynolds number, and offset between upper and lower grooves. The offset 1 (δ_x=1) is found to be the most efficient groove arrangement with a high Nusselt number maintaining the least pressure drop coefficient.

In today's world, where reduction in the carbon footprints is emphasised, people are looking for alternative source of energies for power production and heat treatment of metals and alloys. One such alternative source is solar energy but due to intermittent nature a thermal energy storage (TES) is required in order to deal with heat flux that varies throughout the day so as to supply a constant power. In the present study, the characterization of the sensible heat thermal energy storage (SHTES) packed with sensible heat storage material are considered. The size of pebbles varies between 20-25mm with porosity of the SHTES as 40%. The flow rate is 40 LPM and TES was charged for 8 hours. It has been noticed that when the temperature of the inlet air is around 180°C, the temperature of the top surface of the TES is around 70°C which states that for TES high thermal conductivity materials are required so that charging and discharging can take place at faster rate. The azimuthal and axial variation of temperature is also shown and it is concluded that even after low thermal conductivity of the material azimuthal variation can be neglected for the sake of modeling the TES.

Cold Thermal Energy Storage is an upcoming need for sustainable energy consumption and storage. It finds application in wide variety of energy need in the sub-zero temperature zone. This work aims to study the effect of various surfactants on solidification characteristics of spherically encapsulated DI water with different surfactants. A constant temperature bath at -7°C is used to charge spherical encapsulated PCM using VCR system. Tween 80, Gum Arabic (also known as Gum Acacia) and PVP K30 are selected as surfactants and samples are prepared at various concentrations. To check the feasibility of the sample for thermal energy storage application its thermal properties are determined. Tween 80 and Gum Arabic showed no super cooling and subsequent reduction in super cooling was observed in case of PVP.

Innumerable Nations are enduring biohazard complications because of potable Water contamination. Water contamination is due to the presence of heavy metals like Nickel, Lead, Mercury, copper, iron, manganese, Cadmium, and Zinc in ppb (parts per billion) level. The most effective MEMS-based cantilever design capable of detecting Mercury and Cadmium ionic pressures with better geometry is highly demanded. Heavy metal ion detection in the vapor phase at a particular temperature is highly recommended. The project primly proposes a comparative study of divergent MEMS-based micro-cantilever beam structures with an active layer coating for heavy-metal Mercury and Cadmium ion detection and the structures were appraised based on the mechanical displacement under the pressure influence of target ions. The project proposes a concernment study of the laminar flow of water (liquid) through divergent structural designs. The laminar flow characteristics of water are engaged to find the maximal and minimal velocity and pressure positions. On altering the Inlet flow rates; the outlet flow rate, maximal and minimal velocity and pressure positions vary. Laminar structures were appraised based on the variation of outlet flow rate and pressure with respect to inlet flow velocity. The MEMS-based micro-cantilever structure with superior mechanical displacement is lodged at a maximal pressure locus of laminar flow structures. The pressure quantification at the locus of the micro-cantilever structure is calibrated for Heavy metal: Mercury and Cadmium ions pressure concentration. The finite element analysis of heavy metal Mercury and Cadmium Ion detection is executed using COMSOL Multiphysics 5.4

Producing power in Solar PV panel is simple as all the required data on the performance of various types of panel are available in the field scientific research. As we advance into the future newer and newer technologies are created and evolved according to the needs of the generation. Similarly, in the field of Solar Photovoltaics we have evolved the face of power production from one side to double side. Bi-facial panels are the latest trends which not only produces power on the side facing the sun but also the side facing away. Experimenting on the Bi-Facial Panels to determine the performance, the orientation and placement for the highest LCOE (Levelized cost of electricity) by obtaining the power and radiation data. In this project we have developed various experimental approach to acquire the data required for a Bi-Facial panel setup. The results derived have proved that the new vertical mounting's performance is slightly below the latitude mounted Bifacial Pv panel for the equator regions. Even though the daily comparisons led to a reduction in power level the continuous running of the system proved otherwise.

The heat transfer enhancement in shell and tube heat exchanger can be done by adding Nano particles to the base fluid. The heat transfer rate between hot and cold fluid shows increasing sign with low to high mass flow rate.. Mass flow rate can be controlled and monitored with the help of valve fixed to the shell inlet. Comparing volume concentration of Titanium Nitride from low to high heat enhancement lies linearity. As volume concentration rises in base fluid affect the viscosity of exchange fluid in turn friction of contact fluid increases. Increased mass flow rate and heat transfer helps to find efficiency. The result shows for the controlled same flow rate with common inlet temperature transfer rate of nano fluid is slightly higher with water. Efficiency increase for about 7.47% for water to nanofluid. The effectiveness increase for about 36.6% for water to nanofluid. The LMTD increased for about of 33.6°C and heat transfer rate increases for about 0.4879 kW for three concentrations at one flow rate. Rising the mass flow rate of nano fluid inference in increasing heat transfer.

The present work attempted to analyze the flow structures behind a circular cylinder of different shapes at the subcritical flow regime using unsteady Reynolds averaged equation. Shape ratio variation, circular to an elliptical shape, has been obtained by changing its major to minor axis ratio at Reynolds numbers 200 and 4000. Various flow parameters like drag coefficient, lift coefficient, Strouhal number along with pressure and velocity flow field are analyzed. The primary bulk quantities indicate that the flow characteristics are highly dependable for circular cylinders' shape ratio (SR). The frequency obtained from the vorticity magnitude resembles the natural frequency observed by force coefficients. The formation length increases with increase in Reynolds number, as obtained through the frequency spectrum analysis in the wake region, is highly depends on the shape of the bluff body.

A substantial share of energy goes into building air-conditioning under harsh climatic conditions. The climate control load could be decreased by several means; the proper structure and choice of the building envelope and its components are noteworthy among them. Due to the growing global warming and energy crisis, energy analysis is becoming a major factor to be considered in the industry these days. During the design process, power forecasting is on the rise use and alternative energy is considered as conservation measures and considerations for creating a more energy-efficient building. To minimize the annual energy use and annual cost, the study of the commercial school building has been done by employing various alternatives in the conventional school building model. The different parameters taken for the study are (heating load, cooling load, orientation and lighting control). Analysed the alternative scenarios, and the findings were collected. Each case comparison is based on energy use and the annual cost. The result shows that from the combined use with Autodesk Revit and a Green Building Studio, the integrated energy analysis and design alternatives can provide more building with energy-efficient. The accuracy of the data can greatly affect the results obtained.

Huge competition of the developing countries opens the challenge to create to new technique which make them as super powers. Most of the developing countries economics are mainly depends on the energy sectors which make them to seek alternate. Biofuel is best element which brings them to Independence on other countries. This study investigate the performance and emission characteristics of four stroke diesel engine fuel with mahua oil and Pine oil blend. The fuel was prepared in the volume ratio M30P70, M50P50 and M70P30 and compared with diesel fuel. The experiment was carried out by varying the loading conditions. The experimental results shows M30P70 has higher brake thermal efficiency, lower BSFC because of the lower viscosity of the Pine oil. The emission results show that adding of pine oil in the blend leads to higher Nox emissions because of its lower cetane number of the Pine oil. Co and HC emissions shows reduction pattern because of the lower viscosity of pine oil.

Rapid increment in the energy sector is forcing all countries to look forward to find an alternate solution for their improvements. Biofuel is best alternative which can be easily used in the CI engines. This paper deals with emissions and performance characteristics of CI engine fuelled with Mahua oil blended Camphor Biofuel blend (M70C30, M50C50 and M30C70). Blending the Camphor oil with mahua oil will increase the Brake thermal efficiency. BSFC for M70C30 was found higher than other blended Fuel. Increasing the percentage of camphor in blended fuel will escalate the NOx emissions and will lower the CO, HC and Smoke emissions. M30C70 has higher Thermal efficiency and lower BSFC and which also supports for lowering the HC, CO, Smoke Emissions and high NOx emissions

Economic and Environment constraint of the developing countries brings them in position to find the new substitute for Fuel which is more economic, ecofriendly, higher efficient and sustainable. Many research was carried in the field of high viscous Biofuel which has been changed into straight oil to Biodiesel to suit the Diesel engine. This project deals with CI engine fuelled with low viscous Biofuel and narrate the characteristics of performance and emissions. This paper deals with Mahua oil – Diesel blend (M50), karanja oil – Diesel blend (K50), Turpentine oil-Diesel Blend (T50), Lemon grass oil – Diesel Blend (L50) and Camphor Oil – Diesel Blend. Low Viscosity and high calorific value of T50 supports for higher thermal efficiency and Lower BSFC when Compare to Diesel, C50, L50, K50 and M50. The High Viscous Biofuels M50, K50 has the Higher CO emissions because of improper. Diesel has the lower HC emission than T50, C50, L50, K50 and M50. Low viscous Biofuel T50 and C50 has lower Smoke emissions and higher Nox emissions. The T50 and C50 has the higher heat release rate and higher peak pressure which supports for proper combustion and results in higher BTE, NOx emissions.

Increment in vitality exaction, serious outflow gauges, and consumption of the oil resources prompted chase for elective powers for traditional CI Engines. The examination prompts the exhibition and outflow attributes of CI engine fuelled with linseed oil and diesel is blended inside the mixing proportion B20, B40, B60, B80 with 5% ETBE. The Examination was controlled inside the four stroke single chamber diesel by changing the heap from 20% to 80%. The outcomes delineate that expansion of linseed oil increases the Brake thermal efficiency (BTE) with decrease in Brake Specific Fuel consumption (BSFC) and Temperature of Fumes Gas. Higher concentration of linseed oil within the blends also reduces the emission parameter but with an increment in the Hydro Carbon discharge. The expansion of ETBE in mix with diesel fuel has comparative impact thereto of expansion of unadulterated linseed oil in shifting extents, that increases the brake thermal efficiency with decrease in specific fuel utilization and fumes gas temperature, the impact on the emission characteristics by expansion of lamp oil brings about a lower CO, CO₂, NOx and Smoke with an increase inside the HC discharge. The powerful blending of linseed oil and diesel yield agreeable outcome on the ignition qualities at lower load which shows signs of improvement on increasing the heap.

Nowadays, the consumption of household electricity has been increased with the cost per unit of energy. Due to this, the consumers are pushed in seeking an alternate source of energy such as renewable energy. Thus, solar photovoltaic (PV) systems being small and economically viable modules are coming into action. Even though designing a PV system is has been proven to be a tedious work, not due to the complexity but due to various options that are laid down. Basically, PV systems are divided to standalone, hybrid and grid-connected systems. Solar PV panels are considered as the only source in generating the electricity. Using the simulation software PVSyst, the economic viability of a typical household backup system connected to grid and as a standalone system are analysed. The reliability, performance and financial values of both the systems are compared and presented here.

The ingestion of fossil fuels such as diesel has augmented immeasurably with transformation and increase in the use of automobiles ^[1]. Biodiesel derived from renewable resources such as non-edible vegetable oil is used as a substitute for the conventional diesel fuel. Amplified demand for energy, abridged emission standards and diminution of resources which cannot be renewed claimed in discovering of alternative and non-conventional fuels for IC engines ^[2]. In the subsequent paper, the performance, radiation and characteristics of emission in CI engines powered with turpentine oil. The DEE inclusion has tolerable chattels on the performance characteristics of the fuel, augmented brake thermal efficiency is conquered by the intensification in the extent of DEE and thus consuming the divergent effect on the specific fuel ingesting. The experiment was supported in a 4-stroke, diesel engine of single cylinder by fluctuating the load. Adding Turpentine Oil in diesel raises the aggregate of density, viscosity and level of oxygen content present in it, but diminishes its calorific value ^[2]. Liberation arches depict the same physiognomies as tallying of Turpentine oil which reduces the amount of CO, CO₂, NO_x and O₂ upsurge to quantity of these HC.

Developing countries like India spending huge money in the energy sector and reliable on the other countries which act as the barrier for its own improvement. The developing countries has the constraint in either economic and environment impact because of the higher pollutant released the energy sector like Automobiles. This paper deals with fuel of neem oil and turpentine oil blend in the Proportional of N30T70 (30% of Neem oil and 70% of Turpentine oil) N50T50 ( 50% of Neem oil and 50% of Turpentine oil) and N70T30 ( 70% of Neem oil and 30% of Turpentine oil). Experiment was conducted in four stroke diesel engine by varying load from 0% to 100%. The results shows that increasing the turpentine oil in the blend reduces the viscosity, density and increase the Calorific value blended fuel supports for better combustion. Increase the turpentine oil in blended fuel increase the efficiency, decrease CO and increase the Nox emissions.

To select an alternative fuel suitable for operating an IC diesel engine for real world usage without any major modifications. The need to reduce the use of fossil fuels ignites interest in renewable fuels such as biodiesels. Preventing direct substitution of bio fuels is the higher viscosity of bio fuels. The performance and emission characteristics of CI engine are studied when fuelled with neem oil with diesel blends of ratios B10, B20 and B30 and also with M10% & M20% where methanol is used as the blending agent. The tests were carried out in the 4 stroke, single cylinder diesel engine by varying the load from 25% to 100%.

An aim of project work is to investigate the effect on solidification of phase change material (PCM) in a spherical capsule for cool thermal storage applications. The PCM used as Deionized (DI) water and low-density polyethylene (LDPE) spherical capsule is used as an encapsulation material. It is filled with three different concentration of PCM with NaCl of 0.5, 1.0 and 1.5 wt., % of total volume of encapsulation. An experiments are conducted by immersing the spherical capsules in the constant temperature bath which is maintained at -7°C temperature for all samples. The solidification time is observed in each capsule at various radial locations which correspond to 50%, 75%, and 100% of the mass solidified. The results obtained reveal that the PCM of NaCl has a great influence in reducing the solidification duration. Further, the capsule with 0.5wt.%, shows better results till the solidification of 75% mass than all the other capsules and slows down thereafter. Hence it is concluded that the consideration of DI water with 0.5wt.%, mass of NaCl in the spherical capsule for the design of the energy storage would increase energy efficiency of the system and reduce the energy consumption the chiller.

The purpose of this study is to analyze the impact of the material of the spherical capsule on the solidification characteristics of deionized water as the phase change material(PCM) filled with 90% of its fill volume. The experiment was performed with two same sized balls measuring 86mm diameter made of LDPE(Low density polyethylene) and Stainless Steel kept at distinct bath temperatures(-6,-9 and -12°C). It was noticed that the material of the spherical capsule had an influence on the solidification characteristics of the PCM. The Stainless Steel capsule froze significantly faster than the LDPE capsule for all the mass fractions. This effect was prominent in the lower mass fraction of 50%. It was also inferred that the percentage by which the Stainless Steel capsule froze faster than the LDPE capsule escalated by 32.63%, 40.90% and 43.18% at higher potential temperatures for 50% mass fraction.

As world oil reserves is going down rapidly and the world energy demand is going up, along with the increasing Greenhouse emission, we need to support the initiative by minimizing the emission and maximising the efficiency. We need to grow awareness among people of the importance of Biofuels which will be one of the energy source in the near future. This paper deals with fuel of kapok-Ester oil and Diesel oil blend in the Proportional of (10% of kapok-ester oil and 90% of diesel oil) and B20 (20% of Kapok-ester oil and 80% of Diesel oil).The properties of the blended fuel were measured according to the ASTM standards. The Experiment setup includes of single cylinder four stroke CRDI diesel engine with varying load at constant speed. The experiment results show that increasing the Kapok-ester oil proportion increases the brake thermal efficiency, decrease CO and increase the NOx emission.

In the current study an experimental investigation was carried out with cottonseed oil ester and mineral turpentine oil blend as an alternative fuel in a diesel engine. This study gives the comparative characteristics of performance and emission for the fuel blends and compared with diesel at various injector opening pressures of 190 bar, 210 bar and 230 bar. The experiment was conducted on 5.2 kW single cylinder Compression Ignition engine. Fuel blends in various ratios has been tested. The Turpentine oil was first blended with 20%, 30%, 40% and 50% of cottonseed oil ester to improve the performance of pure turpentine oil as fuel. It was found that the blend T80 which contains 80 % turpentine and 20 % cottonseed oil ester at 210 Bar gives the optimum brake thermal efficiency among all the blends.