Improving the vortex tube parameters using CFD analysis for sustainable manufacturing

Sustainable development will provide innovative methods to lessen manufacturing’s negative environmental effects. Due to the rising desire for a more environmentally conscious populace, sustainability is becoming increasingly crucial in today’s world. Without using power or refrigerant, vortex tubes are a green method of spot cooling. Vortex tubes don’t need to be maintained and are maintenance free. Through this effort, the tube’s parameters will be optimized to raise the cooling temperature. Via CFD study, different vortex tubes with different lengths. Through CFD simulation, the ideal parameters for achieving the lowest cold gas temperature are discovered, including the ideal length of the tube to diameter of the tube ratios, freezing air collection tube diameter (dc), and parameters. By examining the behaviour of vortex tubes with various profiles, length-to-diameter ratios, icy orifice diameters, also a hot end areas using a computerized fluid dynamic tool, it will be possible to demonstrate that they are an alternative and long-lasting instrument for spot cooling in machining operations.


Introduction
In order to cool the cutting edge during the machining operation, the study discussed in this paper is designing a viable clean and renewable tool vortex tube also used to cool the circuit board of a fully automated machine.The vortex tube of Exair brand is shown in figure 1.Sustainable construction referred to by the term making of industrially produced item by utilizing pollution-free techniques, preserve fossil fuels and a variety of sources, and are both financially sensible as well as worker safety., Additionally to battle of market, revenue growth, and yield` care for the environment and sustainable developments referred collectively as the three pillars of sustainability.In order to provide pinpoint chilling, vortex tubes are a viable instrument.Rudolf Hilsch, a German engineer, refined it after French scientist Ranque created it in 1933.Having no working parts, a vortex tube is a simplest gadget.In the vortex tube, cold and warm air under increased pressure separated.The vortex tube is made up of orifices, swirling chambers, inlet nozzle, and central tubes, as well as a control valve and an orifice.High pressure air enters through tangential nozzles in the vortex tube, where it expands and reaches high angular velocities, creating turbulence.With two exit points, a hot end and a cold side, each with a divergent outlet, a vortex tube.The regulating valve is situated on the hot side.At the warm exhaust a control valve manages the rate of mass flow.It's challenging to understand the swirling tube's energy splitting phenomenon.Swirling flow with greater rotational velocities provide a stronger and more effective energy separation effect, which is connected to a power exchange among the two zones that form within the vortex tube.According to Eiamsa-ard [1], the ideal range for cold mass friction (c) is 30% to 40% for maximum cooling temperatures.but so far It is unclear how the energy separates in the vortex tube.The typical and non-invasive flow imaging approaches are challenged by the recirculation nature and high velocity whirling flow described by Aljuwayhel et al [2].A preliminary quantitative tube design technique can be accomplished to attain the important characteristics of the main tube, such as length, diameter, and diameter of the cold exit, based on a basic description of the counter flow structure in a restricted thin tube according to Xiangji Guo et al [3] research.Yunpeng Xue et al [4], show a clear connection between how hot and cold streams are created and how the tube's vortex changes.The temperature drops at the cold side due to the pressure differential in the anterior vortex tube, The heated end's temperature goes up as a result of the inter flow arrangement in the primary tube's periphery.The dimensional parameter of the EXAIR Medieval style with a 15 SCFM vortex tube is given in the Table 1.

CFD Simulation
The Ansys ICEM CFD is used to construct the volume mesh for our component design.It makes use of the common k-epsilon turbulence model.Skye et al. [6] learn about the RNG k-epsilon turbulence model, Yet the outcomes would not match the observational evidence, for this simulation, as well, walls are taken into account as the friction less limit constraint, thus the Reynolds stress equation also cannot converge.The forced and free vortex zones develop within the pipe due to the velocity in the axial direction.Tria components are used in the ICEM mesh generation tool to texture the threedimensional object.Ansys Fluent 14.5 is the volume-based solver used in the current work.In order to solve the vortex tube issue, the solver employed a three-dimensional stable, compressible, pressure-based setup.To record the energy and heat spread, the energy equation was activated.There is a K-epsilon model.In order to calculate the wall friction on a fluid, a two-equation model can be utilized.By using the viscous heating function, it is possible to find the heat loss between the layers.As a material body, air is employed.The ideal gas equation is utilized since it is believed that the flow is compressible.
There is no connection between the surrounding and the energy separation realm.The air temperature is provided as an input in the model along with the definitions of the vortex tube's cold and hot outlets as well as its entrance as a pressure inlet and output as a pressure outlet.We suppose that the wall is an adiabatic state.The mass, momentum, and energy equation was solved using the fluent programme.

Mass balance equation
Momentum balance equation Energy balance equation Ideal gas equation The input values for the intake pressure and inlet ambient temperature are 5.5 bar and 27°c, respectively.Both the hot outlet and the cold outlet have their pressures tuned to the environment.Due to the twofold whirling flow arrangement, the vortex tube separates its energy.The cold end's negative pressure, which is necessary for reverse flow, is formed as a result of pressure differences in the whirling part, hot and cold outlet flow.
In T° The separation of two phases demonstrates a reliable energy transfer among systems, with motion serving as thermal energy in the internal core.
Different gas properties have been linked by research to the influence of the temperature separation.P.Ambedkar et al. [7] so in this project air is taken as a medium for the sustainable cooling system.

Change in design
Although convergent type vortex inlet is employed for length and diameter ratio 5.38 and 2.33 mm orifice radio, the cold end temperature is not improved.Due to wall friction, convergent nozzle lowers entrance velocity.Figure 6 show the vortex inlet with converging inlet nozzle.  2 This result shows that out temperature at cold end is minimum for 5.38 L/D ratio.Energy Separation in the cold end and hot end is shown in Figure 7.

Conclusion
The optimal ratio for the vortex tube length and diameter is found to be 5.39 based on the numerical results of the L/D 19.7, 14.5, 11.76, 11.37, 10.39, 9.31, 8.33, 7.35, and 6.37.At the hot end, 48 degrees Celsius, and at the cold end, 2.37 degrees Celsius were measured length and diameter ratio below the5.39 increase the temperature at cold end.The converging 6 number of tangential inlet also produce high vortex compared to previous single and double inlet.

Figure 1 .
Figure 1.Vortex tube of the EXAIR Medieval style with a 15 SCFM vortex generator

Figure 2 .
Figure 2. Vortex tube designThe circular tube, vortex chamber, vortex generator, barrier, hot side check valve, and six tangential bays make up this whirling pipe.Utilized to regulate the mass movement at the chilly end.By use of the hot side control valve.The mathematical characteristics of the vortex tube, we look at factors

Figure 5 .
Figure 5. Separation of energy in the vortex tube L/D=5.38

Figure 6 .
Figure 6.Vortex inlet that is converging 5. Simulation result Different length and diameter ratio and the cold end out is listed in the Table2This result shows that out temperature at cold end is minimum for 5.38 L/D ratio.Energy Separation in the cold end and hot end is shown in Figure7.

Figure 7 . 6 Figure. 8
Figure 7. Line of energy separation between the cold and hot sides

Figure 9 .
Figure 9. L/D 14.22 Depiction of the outside heat in °C

Figure 11 .7
Figure 11.Two input nozzles Figure 12.L/D 5.38 Cold side heat ranges in degrees Celsius for both holes.

Table 1 .
Vortex tubes Size

Table 2 .
Cold side temperature and thus length and diameter ratio Path line T°c for L/D=5.39