Parameters Affecting the Performance of Single Basin Solar Distillation with Parabolic Reflector: A Detailed Review

The freshwater crisis is already clear in many parts of India. The crisis of fresh water is not the result of natural causes but of human activities. The reason for the need for fresh water is quickly due to the increase in population and the change in lifestyles. The Indian government is playing an important role in fresh water. Nearly 100, 000 children die in India directly after drinking unsafe water each year and approximately 45 million people are affected by diseases due to water pollution, such as excess fluoride, iron or salt water. Single basin solar distillation with parabolic reflector is an excellent device to overcome these problems, which produces drinking water from saline water. In this article, we have studied the problem of several parameters to influence the performance of solar energy. In this work, several techniques were studied to increase the productivity of the still.


Introduction
Still, in rural areas, women and girls have to travel longer to drink fresh water at home. So many hours of the day are spent [1]. There are fresh water problems in many areas of Gujarat and Rajasthan state and fortunately, these areas have more sunlight so we can make the salt water drinkable by using this sunlight. In Haryana and Maharashtra, even in the case of high rainfall, saline water is found [2]. Although there are many types of solar still plants which are conventional in construction as single basin still. Their yields are very less of the order of 1.5 to 4.5 litres per day per m 2 [3]. El-Sebaii investigated computer aided modelling of wind flow effect on still productivity daily basis, which termed as passive solar stills, he experience that active as well as passive productivity can be enhanced by flowing wind up to a reasonable velocity [4]. The various design of still with respect to geographical locations where drinking water can be obtained by solar energy ,have been proposed by many investigators [5][6].Single slope still is very popular, and work on this is going on rigorously [7]. Alnaser had studied about the outcome and its efficiency in the context of single and double basin [8]. He did two tests one for still insulation and other has no insulation. They found that insulation gives comparatively good result to produce potable water, mainly with two basins still, which around 41% higher than single basin system. The technologies are existing for water distillation used, are basically run on thermal engineering concept for distillation as phase conversion or by membrane filtration, which can include categories in two groups. In the first group which is based on thermal technology such as multi-state flashing (MSF), other as multi effective distillation (MED), vapour compression (VC) and the cheapest simple in construction still distillation (SD). The Reverse osmosis (RO) is the  [9]. Due to the running cost of energy consumption these technique and environmental hazards as the use of fossil fuels, they need for reconsideration [10]. Nijmeh investigate the key parameter of solar still generation ,absorptive nature of material at the bottom of basin ,how much radiation it capture which transform in to heating water ,he is mainly focussed on the different material absorption capacities with single basin system like dissolved salts, violet dye, and charcoal etc. He notified that around 25% of still water generation can be improve with salts and violet dye gives better result up to 29%. Since the last few years of decades, thermal distillation mainly dependent on solar power has been appreciated by inventors [11]. But the performances of this type of setup required for more improvement by advancing the cooling and evaporative technology.Thermo-electric refrigeration technique can be utilized as a solid state heat pump which are based on the Peltier effect [12,13]. The main feature of this device have no moving parts, and therefore its more reliable, noiseless, compact in size, easy operation, and environmentally good [14][15]. Due to the appreciation performance of thermo-electric devices, it has become more popular one. The water level in the basin is another parameter to consider by others authors concern their research on convective heat transfer coefficient in between under glass and above water surface in the basin [16].The sponge medium inside water may contribute to enhance still water generation suggested by Abu-Hijleh and Rababa'h [17]. Many researchers have focused on enhancing the performance of solar stills. Rahin et al, [18] used to support this type of techniques to improve still yield. This was done by putting away the evaporating and condensing envelopes, with the help of copper tube for condensation, while using the black aluminum plate at the basin bottom for water evaporation. The efficiency was increased by 31.1%. Abu-Arabi et al. [19] of a solar desalination design model by using double glass collector. If water and glass temperature differences are increased the productivity of distilling water will increase. This is by many people are taking an interest in the field of solar still. The performance of concave wick evaporation of solar had been studied by still Kabeel [20]. The still produces 4.1 L/m 2 as the average daily production of his still which has 30% average efficiency. The productivity of a weir-type inclined solar still studied by Sadineni et al. [21]. This still's daily production was 5.5 L/m 2 if thin water films uses and temperature difference of evaporation and condensation increased. Phadatare et al. [22] used the same data to observe the effect of water depth. From last few years more people are coming forward to take part in improving solar still performance and to get more productivity they have made a simple still. Mirza et al. [23] proposed a design of simple basin solar still, properties were measured and its still efficiency was 30% and its daily productivity was was 3.1 L/m 2 . His research said that the outcome of the solar still varies with the factor of insulation and surrounding temperature. Srithar [24] quoted the still productivity increases if wick, fin and sponge con enhance the outcome of the sill, he reported that the productivity of the still increased by 45.5 %, 15.3% and 29% with fin, sponge and wick, respectively. Mathematical modelling was incorporated to estimate the generation of distil water with various aspect of surrounding such as weather, design of setup and operational condition like shallow water basin and insulation had great productivity [25] . Although numerical simulation study based on unsteady Navier-Stokes equation in the conjunction of different fluid properties like Nusselt no. for different pair of medium and temperature differences were studied [26]. Transient model for analytical solution of the energy -balance was investigated by Aboul-Enein [27].During the numerical investigation, the influence of water film covering the top of glass play an important role to increase the still water generation, and around 21% still efficiency increases with it. Computer aided modelling was performed to get futuristic parameters of single slope solar still by taking temperature difference between top and bottom surface temperatures by concluding effect of this on heat convection coefficient [28].

Working principle of single basin solar distillation with parabolic reflector
Sunlight is collected in a variety of ways in which the saltwater located on it is converted into vapour. In this study, we have also used a reflector with single basin solar still. When sunlight strikes on the glass of solar still, the water in the basin becomes warm. The use of parabolic reflectors increases the 3 rate of warm. The hot water turns upwards. This vapour is collected un remain in the basin; steam gets cond the gravity or slope the glass, these d 3. Factors affecting the productivi Particular effects are influencing the of sun controlled radiation, wind sp without water covering a zone, cent and glass spread point. The intensi can't be controlled in light of how climbed to improve the sun based s sun organized still benefit, distinct capacity [29].

Area of the solar basin still
The zone of sun oriented still assu event that the region builds, the effic

Depth of water in solar basin
Khalifa and Hamood led investigate profundity in the sun oriented still b expanding water profundity in the b into the vapour, and this vapour goes the inner su nder the glass as small droplets. By which almost al densed and convert into water droplet/like a sheet o droplets begin to fall and collect it in one place. ity single basin solar distillation with parabolic re e sun filled still preferred standpoint, for instance, t peed, ordinary temperature, glass -water temperatu trality of water, sound water temperature, a territory ity of sun based radiation, wind speed and tradema they are metrological determinants. Exchange para still ampleness. By isolating the unmistakable piece tive adjustments have been made to develop the umes a fundamental job in the generation of refined ciency of sun powered still keeps on expanding. e sun powered still that utilization distinctive dimen bowl [30]. They inspected that the rate of vanishing d owl.

Inlet saline water temperature
Studies have shown that from highe more. So by applying the parabolic will be increased.

Glass inclination and thickness o
Jordan, Khalifa and Hamood direct outcome that efficiency can increm of glass is equivalent to the scope o [32] analyzed, if the point of the gla stretch of May.

Temperature gradient between g
In the event that the temperature co of saline water is increment. This t water, which go about as a main utilizing twofold glasses, splash of w  570N) ent up to 63% [30]. Singh and Tiwari [31] inspecte of the spot; the efficiency of refined water will be hi ass is 35 degrees, the most noteworthy refining happ Still with Glass inclination and thickness of glass glass cover and water ontrast among glass and water is expanded, the rate temperature contrast assumes a fundamental job am thrust for the buildup. Temperature distinction ac water on the upper side on glass [33][34].
ith Temperature gradient between glass cover and wa e execution of the solar still ar still by utilizing energy absorption and putting awa   nd wick material out the execution of sun based still with different su wipe, quartzite shake and trademark shake and sur ageous effectiveness. Nafey et al. [36] inspected th e and contemplated that the productivity of sun po 37] thought about the execution of sunlight based sti solidified steel, mica, and aluminum and assu % for mica. Sakthivel  framework contains a hilter kilter, light based gatherer and field storin sun based authority was coursed by with a measurement plate pro. The preheated water to the bowl water.

Figure Conclusion
There are following conclusions afte A. Factors affecting the produc 1. Insulation thickness pla can be increase with Ins 2. In production of distille glass is same of latitude 3. Solar still productivity α 4. Solar still yield α Intens B. Techniques used to improve 1. By utilizing Sponge cub 2. Productivity of sun orie single-influence sun energized still, a joined a mea ng up tank as appeared in Figure 7. The preheated y a barrel through the bowl water or sun orchestra barrel is filling in as a sparkle exchanger, and trade