Journal articles: 'Vortex Tube - Refrigeration System'

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Puangcharoenchai, Phupoom, Pongsakorn Kachapongkun, Phadungsak Rattanadecho, and Ratthasak Prommas. "Experimental Investigation of Performance Enhancement of a Vapor Compression Refrigeration System by Vortex Tube Cooling." International Journal of Air-Conditioning and Refrigeration 28, no. 02 (June 2020): 2050018. http://dx.doi.org/10.1142/s2010132520500182.

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This study aimed to analyze the difference in operation of the vapor compression refrigeration (VCR) system with vortex tube cooling. By using varied loads, experiments were conducted on the evaporator section of a vapor compression refrigeration system. In an attempt to improve the use of subcooling for the refrigeration, the effect of subcooling of refrigerant by vortex tube cooling was likewise examined. The test conditions included various loads (25%, 50%, 75% and 100%) and cold mass fractions (25%, 50% and 75%). This research described coefficient of performance (COP) as one of the significant parameters, in addition to heat rejection and refrigerating effect. The ideal efficiency appeared to be with the cold mass fraction of 25% and load of 100%, as identified by the results. Consequently, the COP could be enhanced by 5.16% along with an approximately 4.36% decline in average power use. Improved guidelines for vapor compression refrigeration systems to enhance the operation of the system are an expected benefit of this study.

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Sreenivasa Kumar Reddy, B., and K. Govindarajulu. "Air Cooling in Automobiles Using Vortex Tube Refrigeration System." Applied Mechanics and Materials 592-594 (July 2014): 1408–12. http://dx.doi.org/10.4028/www.scientific.net/amm.592-594.1408.

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Refrigeration plays an important role in developing countries, primarily for the preservation of food, medicine, and for air conditioning. Conventional refrigeration systems are using Freon as refrigerant. As they are the main cause for depletion of ozone layer, extensive research work is going on alternate refrigeration systems. Vortex tube is a non conventional cooling device, having no moving parts which will produce cold air and hot air from the source of compressed air without affecting the environment.

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Vivek, G. "Performance Analysis of Vortex Tube Refrigeration System by Experimental Method and Using ANN." Asian Review of Mechanical Engineering 11, no. 2 (December 15, 2022): 25–30. http://dx.doi.org/10.51983/arme-2022.11.2.3478.

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Vortex tube is a non-conventional cooling device, having no moving parts which will produce cold air and hot air from the source of compressed air without affecting the environment. When a high-pressure air is tangentially injected into vortex chamber, a strong vortex flow will be created which will split into two air streams, one hot stream at the periphery and the other cold stream at the inner core on both the ends. It can be used in the industrial applications such as spot cooling of cutting tools, heating process, refrigerators etc. It is weightless and requires less space. Also, the initial cost is low and its working expenses are less where compressed air is readily available. The present work is to analysis the performance of vortex tube by changing the mass flow rate of air at inlet and cold outlet. Vortex tube refrigeration system set up is fabricated with the help of instruments such as rotameter, pressure transmitter and RTD temperature sensors. In this experiment, a small vortex tube which is made up of stainless steel is used. The vortex tube is well insulated with a suitable insulating material. The experiment is carried out by varying the thermo-physical properties of the compressed air which is used as working fluid. By regulating the hot end control knob of vortex tube, the pressure, mass flow rate and temperature of air is measured at different points for various inlet working pressure.

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Bedare, Sitaram, Dr Ajay Chavan, Prof Bhushan karamkar, and Prof Mayuri Mhaske. "Experimental Investigation and Analyze the Effect of Varying L/D on Thermal Performance of Vortex Tube." International Journal of Innovative Research in Advanced Engineering 10, no. 06 (June 26, 2023): 403–7. http://dx.doi.org/10.26562/ijirae.2023.v1006.30.

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Traditional vapour compression systems are known to be costly and require regular maintenance due to their numerous moving parts. However, a promising alternative is the vortex tube refrigeration system, which operates without any moving components. This system functions as a miniature refrigerator by effectively dividing the compressed gas into two separate streams: one hot and one cold. In order to maximize the temperature reduction achieved by this system, a study was conducted to assess its thermal performance based on various geometric parameters. Specifically, the investigation focused on the influence of the length-to-diameter (L/D) ratio of the vortex chamber under different inlet pressure conditions. Experimental trials were conducted with different L/D ratios, and the analysis primarily focused on the extent of low temperature fraction attained. The results highlighted the significance of the L/D ratio in determining the overall performance of the vortex tube cooling system

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Li, Jun, Lei Xu, Nian Yong Zhou, Yan Long Jiang, and He Xu Wang. "Design and Research of Vortex-Tube-Ice-Storage System Used in Refuge Chamber." Applied Mechanics and Materials 741 (March 2015): 9–14. http://dx.doi.org/10.4028/www.scientific.net/amm.741.9.

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When disasters occur under coal mines, the electric power system and compressed air system would be highly vulnerable to damage, while heat load will be produced in the chamber because of victims’ metabolism and equipments’ operation, so it is crucial to control temperature in the chamber effectively. This paper presents a new type of vortex tube ice storage refrigeration technology, and the property of a vortex tube is tested and theory of the ice storage system is studied, then the ice making time and the best working state are obtained. It provides theoretical basis for ice storage refrigeration of mine rescue, and it is of important reference value for engineering design.

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Xie, Ying Bai, Kui Kui Cui, Zhi Chao Wang, and Jian Lin Liu. "CO₂ Trans-Critical Two Stage Compression Refrigeration Cycle with Vortex Tube." Applied Mechanics and Materials 52-54 (March 2011): 255–60. http://dx.doi.org/10.4028/www.scientific.net/amm.52-54.255.

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The paper analyses CO2 trans-critical two stage compression refrigeration cycle with vortex tube expansion by thermodynamics method. And compare with CO2 trans-critical two stage compression refrigeration cycle with expansion value. The results show that in the calculated conditions of the paper, the performance of the cycle with vortex tube improves 2.4%~16.3% than the cycle with expansion value. The optimal discharge pressure maximizing COP of the cycle with vortex tube exists. With lower evaporating temperature or higher gas cooler exit temperature, COP of system decreases and COP improvement increases. The effect of cold fluid mass fraction on COP is not significant, but COP improvement increases more quickly with cold gas mass fraction increasing.

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Liu, Yefeng, Ying Sun, and Danping Tang. "Analysis of a CO2 Transcritical Refrigeration Cycle with a Vortex Tube Expansion." Sustainability 11, no. 7 (April 4, 2019): 2021. http://dx.doi.org/10.3390/su11072021.

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A carbon dioxide (CO2) refrigeration system in a transcritical cycle requires modifications to improve the coefficient of performance (COP) for energy saving. This modification has become more important with the system’s more and more widely used applications in heat pump water heaters, automotive air conditioning, and space heating. In this paper, a single vortex tube is proposed to replace the expansion valve of a traditional CO2 transcritical refrigeration system to reduce irreversible loss and improve the COP. The principle of the proposed system is introduced and analyzed: Its mathematical model was developed to simulate and compare the system performance to the traditional system. The results showed that the proposed system could save energy, and the vortex tube inlet temperature and discharge pressure had significant impacts on COP improvement. When the vortex tube inlet temperature was 45 °C, and the discharge pressure was 9 MPa, the COP increased 33.7%. When the isentropic efficiency or cold mass fraction of the vortex tube increased, the COP increased about 10%. When the evaporation temperature or the cooling water inlet temperature of the desuperheater decreased, the COP also could increase about 10%. The optimal discharge pressure correlation of the proposed system was established, and its influences on COP improvement are discussed.

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Sarkar, Jahar. "Exergy analysis of vortex tube expansion vapour compression refrigeration system." International Journal of Exergy 13, no. 4 (2013): 431. http://dx.doi.org/10.1504/ijex.2013.058101.

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9

Liu, Yefeng, and Jun Yu. "Review of vortex tube expansion in vapour compression refrigeration system." IOP Conference Series: Earth and Environmental Science 153 (May 2018): 032021. http://dx.doi.org/10.1088/1755-1315/153/3/032021.

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Pouraria, Hassan, and Warn-Gyu Park. "Numerical investigation on cooling performance of Ranque-Hilsch vortex tube." Thermal Science 18, no. 4 (2014): 1173–89. http://dx.doi.org/10.2298/tsci120610052p.

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A Ranque-Hilsch vortex tube (RHVT) is a mechanical device that separates a high pressure gas stream into low pressure hot and cold streams. In this study, four different two equation turbulence models namely the standard k-?, RNG k-?, Realizable k-? and standard k-? models were compared to identify the appropriate turbulence model for studying the energy separation effect in a RHVT. Comparison between the numerical and experimental results indicates that the standard k-? model is better than other models in predicting the energy separation phenomenon. The distributions of temperature, pressure, and components of velocity have been obtained in order to understand the flow behavior inside the tube. The effect of cold outlet diameter on temperature drop and refrigeration capacity was studied. The effect of cold mass fraction on the movement of stagnation point and refrigeration capacity has been investigated. Moreover, the feasibility of improving the cooling performance of vortex tube using the cooling system was investigated. The present numerical results revealed that using the cooling system, the net energy transfer rate from cold inner region to the hot peripheral region increases, thereby improving the cooling performance of the device.

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11

Liu, Ying Fu, Chun Jing Geng, and Guang Ya Jin. "Vortex Tube Expansion Transcritical CO2 Heat Pump Cycle." Applied Mechanics and Materials 190-191 (July 2012): 1340–44. http://dx.doi.org/10.4028/www.scientific.net/amm.190-191.1340.

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The application of natural refrigerant CO2 is of great significance to reduce the greenhouse effect and ozone depletion. Transcritical CO2 heat pump cycle is presently an important aspect of natural refrigerant alternatives research. In this paper, a vortex tube expansion transcritical CO2 heat pump cycle is established and compared to that of the transcritical CO2 refrigeration cycle with throttle valve. Thermodynamic analysis results indicate that the system performance of vortex tube expansion transcritical CO2 heat pump cycle is better than the transcritical CO2 heat pump cycle with throttle valve, and the COPh improvement is 5.8%~13.9% at given conditions. The gas-cooler outlet temperature has a great impact on the system performance, there is a higher COPh improvement when the cycle at lower evaporation temperature or higher gas-cooler outlet temperature.

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Xu, Qijun, Jinfeng Wang, and Jing Xie. "3D Numerical Simulation and Performance Analysis of CO2 Vortex Tubes." Applied Sciences 11, no. 20 (October 9, 2021): 9386. http://dx.doi.org/10.3390/app11209386.

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In view of the extensive application of swirl flow pipes (vortex tubes) in refrigeration systems, the parameters of swirl flow pipes were investigated to provide optimal cooling and heating conditions. Three-dimensional numerical simulations were carried out using available experimental data and models. The analysis verified that the heat pipe with a length of 175 mm performed better than the swirl flow pipe with a length of 125 mm, confirming experiments by Agrawal. Meanwhile, by comparing different pressures, it was found that in the single-nozzle swirl flow pipe, the greater the increase of pressure (0.1–1.0 MPa), the greater the burden on the vortex chamber and the more serious the wear is, which can be seen in the higher inlet pressure. In order to improve the durability of the swirl flow pipe, we suggest using a swirl flow pipe with more nozzles. Finally, according to the simulation results, with the rise of carbon dioxide pressure potential energy at the inlet, the cooling effect of the swirl flow is first increasing and then decreasing. When the swirl flow pipe is used as a refrigeration device to determine the minimum cooling temperature under the maximum pressure, the lowest temperature of the 125 mm swirl flow pipe was 252.4 K at 0.8 MPa, while the lowest temperature of the 175 mm swirl flow pipe was 246.0 K. Secondly, the distance from the inlet to the hot outlet of the swirl flow pipe had little effect on the cooling temperature and radial velocity, but increasing its distance increased the wall temperature of the swirl flow pipe because it increases the contact time between the airflow and the hot end of the tube wall. When the swirl flow pipe is used as a heat-producing device, increasing the tube length of the swirl flow pipe appropriately increases its maximum heat-producing temperature.

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Hasan, Sahira, and Zianab H. Naji. "AUGMENTATION HEAT TRANSFER IN A CIRCULAR TUBE USING TWISTED - TAPE INSERTS: A REVIEW." Journal of Engineering and Sustainable Development 27, no. 4 (July 1, 2023): 511–26. http://dx.doi.org/10.31272/jeasd.27.4.8.

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Heat transfer enhancement is the process of increasing the heat-transfer coefficient, which enhances the system's performance. Enhancing heat transfer is a major problem for saving energy and is also beneficial economically. Many passive devices are used inside tubes to improve heat transfer such as twisted tape inserts, rough parts, extended surfaces, additives for liquids wire plugs, etc. This research reviewed one of the most effective passive devices which are twisted tape inserts. Since it has many advantages such as simple fabrication, simple operation, and ease of maintenance. The twisted tape inserts generated swirl flow and vortex inside the tube. Therefore, the internal convective heat transfer process is significantly improved. The current research article provides an overview of different twisting tape inserts that can improve heat transfer rates. By reducing boundary layer thickness near tube walls. Which lead to reduce the size and cost of many industrial applications, including heat exchangers, refrigeration systems, air conditioners, reactors, thermal power plants, spacecraft, and automobiles. A summary of previous experimental and numerical studies is presented as well. The primary results indicated that the twisted tape inserts are demonstrated to be efficient in enhancing heat transfer inside the tube for laminar and turbulent flow. But during a turbulent flow, twisted tapes increased pressure loss more than laminar flow because of flow obstruction.

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14

Liu, Ying Fu, and Guang Ya Jin. "Vortex Tube Expansion Two-Stage Transcritical CO₂ Refrigeration Cycle." Advanced Materials Research 516-517 (May 2012): 1219–23. http://dx.doi.org/10.4028/www.scientific.net/amr.516-517.1219.

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Use of vortex tube as an expansion device in transcritical CO2 cycle could reduce the throttle loss and improve the coefficient of performance. In this paper, a vortex tube expansion two-stage transcritical CO2 refrigeration cycle(VTTC) is established and compared to that of the two-stage transcritical CO2 refrigeration cycle with throttle valve(TVTC). Thermodynamic analysis results indicate that there is also an optimum heat rejection pressure for the vortex tube cycle, and the COP improvement is 2.4%~16.3% at given conditions. Decrease in evaporation temperature or increase in gas-cooler outlet temperature decrease the COP, but the COP improvement will increase. The effect of cold mass fraction on the COP is negligible, but the COP improvement will increase fast with the increase of cold mass fraction.

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15

Ahlborn, Boye K., and Jeffrey M. Gordon. "The vortex tube as a classic thermodynamic refrigeration cycle." Journal of Applied Physics 88, no. 6 (September 15, 2000): 3645–53. http://dx.doi.org/10.1063/1.1289524.

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Raghu Vamsi, B. V. S., Repalle Jithendra Kumar, M. R. C. Sastry, T. Siva Krishna, and M. Kamal Tej. "Experimental Investigation on the Performance of Vortex Tube." Advanced Materials Research 1148 (June 2018): 115–21. http://dx.doi.org/10.4028/www.scientific.net/amr.1148.115.

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Non-conventional systems are developed to produce cooling effect which use eco-friendly refrigerants and consuming less energy as input. In this work, a vortex tube refrigerator is fabricated from CPVC material, to which air is supplied through five tangential inlet nozzles at different inlet pressures. The inlet pressure is varied over a span of 1 kg/cm2 to 8 kg/cm2 with an interval of 1 kg/cm2. The difference between the temperatures of hot and cold air streams at outlet is observed to be increasing with time as well as for different inlet pressures. In addition the COP for the cold end side is observed to be more than at the hot end side and isentropic efficiency is observed to be increasing with inlet pressures.

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Yakubov, Sabir, Abdusaid Isakov, Rashida Pirova, and G. Shadmanova. "Automatic control of active ventilation systems in agricultural products storage facilities." E3S Web of Conferences 365 (2023): 04026. http://dx.doi.org/10.1051/e3sconf/202336504026.

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The article recommends automatic control of active ventilation systems in agricultural product storage facilities. The search for rational solutions for ventilation, heating, and automatic control systems (ACS) that improve product storage quality and methods and means of storage is considered. As a result of the analysis of the requirements for air-cooling storage units that operate for no more than 25 days per annual storage cycle, it was proved that refrigerating arrangements that are based on the principle of operation of vortex energy separators - vortex tubes (VT) meet these requirements most fully. In terms of temperature effect, the VT is inferior to the expander by 1.3 ... 1.5 times, in terms of cooling capacity by 3.0 ... 3.5 times. Compared to the throttling process, vortex tubes, when operating in air, are about 30 times better in terms of temperature effect and 15 times better in terms of cooling capacity.

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Liu, Yefeng, Ying Sun, and Dongliang Wang. "Research on carbon dioxide transcritical refrigeration cycle with vortex tube." IOP Conference Series: Earth and Environmental Science 267 (June 8, 2019): 022010. http://dx.doi.org/10.1088/1755-1315/267/2/022010.

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Isakadze, Tamaz, and Givi Gugulashvili. "Carbon Dioxide Recuperation Using a Ranque-Hilsch Vortex Tube for Refrigerated Food Processing." Works of Georgian Technical University, no. 3(521) (September 29, 2021): 109–14. http://dx.doi.org/10.36073/1512-0996-2021-3-109-114.

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The disadvantage of the technological process of freezing food products using carbon dioxide is the irrational use of its waste vapors. From the authors’ point of view, it is desirable to use carbon dioxide not only directly on the line for freezing and cooling food raw materials. Cooling of carbon dioxide vapors after processing on freezing lines with further use for refrigeration looks promising, for example, for freezing food materials, for which the freezing temperature according to the technological instructions can be higher than the boiling point of carbon dioxide -78 ℃. An innovative refrigeration machine based on a Ranque-Hilsch vortex tube has been developed for cooling waste carbon dioxide for further use in the refrigeration processing of food products. It is based on carbon dioxide recovery technology.

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Jain, Gaurav, Akhilesh Arora, and S. N. Gupta. "Performance analysis of a transcritical N2O refrigeration cycle with vortex tube." International Journal of Ambient Energy 40, no. 4 (November 13, 2017): 350–56. http://dx.doi.org/10.1080/01430750.2017.1399449.

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Raja, Niraj N., and Avinash D. Khanderao. "Experimental Investigation on the Effect of Capillary Tube Geometry on the Performance of Vapor Compression Refrigeration System." Asian Journal of Engineering and Applied Technology 5, no. 2 (November 5, 2016): 29–35. http://dx.doi.org/10.51983/ajeat-2016.5.2.802.

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The study of the expansion device in simple vapor compression refrigeration system is necessary in order to understand the parameters which can enhance the overall performance of system. It is essential to study the effect of capillary tube geometry on the performance of refrigeration systems. The literature review focuses on the effect that geometrical parameters like capillary tube length, bore diameter, coil pitch, number of twist and twisted angle have on the pressure drop, coefficient of performance (COP) and mass flow rate of the system. The parameters stated above can be further optimized in order to enhance the performance of the refrigeration system. The present work is focused on the influence of tube diameter, tube length, coil pitch, and inlet condition on mass flow rate of refrigerant through helical coil capillary tube and also on investigation about the Coefficient of Performance (COP) of the system due to coiling effect of capillary tube. The use of helical capillary tube reduces the space for the refrigeration system which is the need for more compact refrigeration system in the current trend.

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Jain, Gaurav, Akhilesh Arora, and Shambhu Nath Gupta. "Exergy analysis of the transcritical N2O refrigeration cycle with a vortex tube." International Journal of Green Energy 15, no. 9 (June 18, 2018): 507–16. http://dx.doi.org/10.1080/15435075.2018.1486315.

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Sairamakrishna, B., T. Gopala Rao, and N. Rama Krishna. "Cop Enhancement of Vapour Compression Refrigeration System." Indian Journal of Production and Thermal Engineering 1, no. 2 (June 10, 2021): 1–6. http://dx.doi.org/10.35940/ijpte.b2004.061221.

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This experimental investigation exemplifies the design and testing of diffuser at compressor inlet and nozzle at condenser outlet in vapour compression refrigeration system with the help of R134a refrigerant. The diffuser with divergence angle of 12°,14° and the nozzle with convergent angle 12°,14° are designed for same inlet and outlet diameters. Initially diffusers are tested at compressor inlet diffuser is used with inlet diameter equal to exit tube diameter of evaporator and outlet tube diameter is equal to suction tube diameter of the compressor. Diffuser helps to increases the pressure of the refrigerant before entering the compressor it will be helps to reduces the compression work and achieve higher performance of the vapour compression refrigeration system. Then nozzles are testing at condenser outlet, whereas nozzle inlet diameter equal to discharging tube diameter of condenser and outlet diameter equal to inlet diameter of expansion valve. Additional pressure drop in the nozzle helped to achieve higher performance of the vapour compression refrigeration system. The system is analyzes using the first and second laws of thermodynamics, to determine the refrigerating effect, the compressor work input, coefficient of performance (COP).

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B, Sairamakrishna, T. Gopala Rao, and Rama Krishna, N. "Cop Enhancement of Vapour Compression Refrigeration System." Indian Journal of Production and Thermal Engineering 1, no. 2 (June 10, 2021): 1–6. http://dx.doi.org/10.35940/ijpte.b2004.06122.

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This experimental investigation exemplifies the design and testing of diffuser at compressor inlet and nozzle at condenser outlet in vapour compression refrigeration system with the help of R134a refrigerant. The diffuser with divergence angle of 12°,14° and the nozzle with convergent angle 12°,14° are designed for same inlet and outlet diameters. Initially diffusers are tested at compressor inlet diffuser is used with inlet diameter equal to exit tube diameter of evaporator and outlet tube diameter is equal to suction tube diameter of the compressor. Diffuser helps to increases the pressure of the refrigerant before entering the compressor it will be helps to reduces the compression work and achieve higher performance of the vapour compression refrigeration system. Then nozzles are testing at condenser outlet, whereas nozzle inlet diameter equal to discharging tube diameter of condenser and outlet diameter equal to inlet diameter of expansion valve. Additional pressure drop in the nozzle helped to achieve higher performance of the vapour compression refrigeration system. The system is analyzes using the first and second laws of thermodynamics, to determine the refrigerating effect, the compressor work input, coefficient of performance (COP).

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Sairamakrishna, B., T. Gopala Rao, and N. Rama Krishna. "Cop Enhancement of Vapour Compression Refrigeration System." Indian Journal of Production and Thermal Engineering 1, no. 2 (June 10, 2021): 1–6. http://dx.doi.org/10.54105/ijpte.b2004.061221.

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This experimental investigation exemplifies the design and testing of diffuser at compressor inlet and nozzle at condenser outlet in vapour compression refrigeration system with the help of R134a refrigerant. The diffuser with divergence angle of 12°,14° and the nozzle with convergent angle 12°,14° are designed for same inlet and outlet diameters. Initially diffusers are tested at compressor inlet diffuser is used with inlet diameter equal to exit tube diameter of evaporator and outlet tube diameter is equal to suction tube diameter of the compressor. Diffuser helps to increases the pressure of the refrigerant before entering the compressor it will be helps to reduces the compression work and achieve higher performance of the vapour compression refrigeration system. Then nozzles are testing at condenser outlet, whereas nozzle inlet diameter equal to discharging tube diameter of condenser and outlet diameter equal to inlet diameter of expansion valve. Additional pressure drop in the nozzle helped to achieve higher performance of the vapour compression refrigeration system. The system is analyzes using the first and second laws of thermodynamics, to determine the refrigerating effect, the compressor work input, coefficient of performance (COP).

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Roy, Prokash C. "THERMODYNAMIC MODELING OF A PULSE TUBE REFRIGERATION SYSTEM." Journal of Thermal Engineering 4, no. 1 (December 12, 2017): 1668–79. http://dx.doi.org/10.18186/journal-of-thermal-engineering.364889.

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Jain, Gaurav, Akhilesh Arora, and S. N. Gupta. "Performance characteristics of a two-stage transcritical N2O refrigeration cycle with vortex tube." International Journal of Ambient Energy 41, no. 5 (May 21, 2018): 491–99. http://dx.doi.org/10.1080/01430750.2018.1472646.

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Raut, Ashish, and Uday Wankhede. "Review of investigations in eco-friendly thermoacoustic refrigeration system." Thermal Science 21, no. 3 (2017): 1335–47. http://dx.doi.org/10.2298/tsci150626186r.

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To reduce greenhouse gas emissions, internationally research and development is intended to improve the performance of conventional refrigeration system also growth of new-fangled refrigeration technology of potentially much lesser ecological impact. This paper gives brief review of research and development in thermoacoustic refrigeration also the existing situation of thermoacoustic refrigeration system. Thermoacoustic refrigerator is a novel sort of energy conversion equipment which converts acoustic power into heat energy by thermoacoustic effect. Thermoacoustic refrigeration is an emergent refrigeration technology in which there are no moving elements or any environmentally injurious refrigerants during its working. The concept of thermoacoustic refrigeration system is explained, the growth of thermoacoustic refrigeration, various investigations into thermoacoustic refrigeration system, various optimization techniques to improve coefficient of performance, different stacks and resonator tube designs to improve heat transfer rate, various gases, and other parameters like sound generation have been reviewed.

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Liu, Xinhui, Yan Yan, Jiping Lu, and Yafeng Han. "Numerical simulation study on the influence of scroll design parameters on helicopter intake system." Journal of Physics: Conference Series 2383, no. 1 (December 1, 2022): 012001. http://dx.doi.org/10.1088/1742-6596/2383/1/012001.

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Based on the numerical simulation theory, this paper establishes the two-phase flow calculation model of sand and air mixture in the sand control vortex tube, and combined with CFD numerical simulation, studies the influence rules of various design parameters of the vortex tube on the total pressure loss and sand dust separation efficiency of the helicopter intake system, optimizes the structural parameters of the vortex tube separator, and puts forward a set of vortex tube design method, it provides a basis for the design optimization of vortex tube.

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Guo, Qianjian, Xiaoni Qi, Zheng Wei, Pengjiang Guo, and Peng Sun. "3D Numerical Simulation and Analysis of Refrigeration Performance of the Small Diameter Vortex Tube." International Journal of Heat and Technology 34, no. 3 (September 30, 2016): 513–20. http://dx.doi.org/10.18280/ijht.340324.

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DABAS, J. K., SUDHIR KUMAR, A. K. DODEJA, and K. S. KASANA. "EXPERIMENTAL INVESTIGATION OF A REFRIGERATION SYSTEM WORKING UNDER TRANSIENT CONDITIONS." International Journal of Air-Conditioning and Refrigeration 22, no. 03 (September 2014): 1450013. http://dx.doi.org/10.1142/s2010132514500138.

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The impact of transient conditions along with varied capillary tube length and charge quantity over the performance of a simple refrigeration system under all time transient operations has been investigated in a specially designed experimental setup. A maximum drop of 75% in the coefficient of performance (COP) of the system was recorded by the end of the transient cooling period. The continuous deterioration in performance from start to end of the transient cooling job can be well minimized by the optimum selection of capillary tube length and charge quantity. This paper refers some of the existing methods to determine the appropriate length of the coiled capillary tube and charge quantity for a newly designed refrigeration machine working under steady state conditions and compares the experimental results of transient operation with these. Optimum charge quantity for transient operation in the present study is 3.5% to 5% less than that calculated by the existing analytical and numerical methods. The optimum length of coiled capillary tube for transient operation as found in this experimental study matches approximately with the length predicted by the existing dimensionless correlation on the basis of design parameters as estimated towards the end of the transient cooling period.

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Salim, Thamir K. "The Effect of the Capillary Tube Coil Number on the Refrigeration System Performance." Tikrit Journal of Engineering Sciences 19, no. 2 (June 30, 2012): 18–29. http://dx.doi.org/10.25130/tjes.19.2.03.

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The capillary tube performance for (R134a) is experimentally investigated. The experimental setup is a real vapor compression refrigeration system. All properties of the refrigeration system are measured for various mass flow rate from (13 – 23 kg/hr) and capillary tube coil number (0-4) with fixed length (150 cm) and capillary diameter (2.5mm).The results showed that the theoretical compression power increases by (65.8 %) as the condenser temperature increases by (2.71%), also the theoretical compression power decreases by (10.3 %) as the capillary tube coil number increases.The study shows also that the cooling capacity increases by (65.3%) as the evaporator temperature increases by (8.4 %), and the cooling capacity increases by (1.6%)as the capillary tube coil number increases in the range (0-4).The coefficient of performance decreases by (43.4 %), as the mass flow rate increases by (76.9%), also the coefficient of performance increases by (13.51 %) as the capillary tube coil number increases in the range (0-4).Through this study, it was found that the best coil number in refrigeration cycle at the lowest mass flow rate (31 Kg/hr) and at high mass flow rate (23 Kg/hr) is (coil number = 4), this will give the highest performance, cooling capacity and lowest theoretical compression power.An experimental relationship has been adopted between the coefficients of performance (COP) against (- 5.6032+e 0.0413*nco. /0.0051*m ).

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Yang, Juan Juan, Ke Li, and Xin Yang Cui. "Experimental Study on Miniature-Refrigeration System." Key Engineering Materials 531-532 (December 2012): 584–87. http://dx.doi.org/10.4028/www.scientific.net/kem.531-532.584.

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A prototype of miniature cooling system was developed, which mainly consists of the miniature compressor from DONG YUAN and a spiral-tube evaporator designed by ourselves. The performances of the prototype with different parameters were tested. The influence of ambient temperature, chilled water temperature on the performance of the cooling system were analyzed. The best operating conditions and the optimum amount of refrigerant were obtained. Conclusions were gotten as follows:1) With environment temperature rising, compression ratio increases, system power consumption increases and refrigerating capacity COP decreases. 2) With chilled water temperature rising, compression ratio and power consumption decrease, refrigerating capacity increases, and COP increases rapidly.3) Paper gets system performance: refrigerating capacity is 63 W, compressor power consumption is 24.5 W, COP value is 2.57. in operation condition: refrigerant amount is 40g, environment temperature is 30°C, chilled water temperature is 40 °C, chilled water mass flow is 45 kg/h.

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Stanescu, George. "Twice Optimized Evaporative Cooling System with Vortex Tube." Defect and Diffusion Forum 370 (January 2017): 103–12. http://dx.doi.org/10.4028/www.scientific.net/ddf.370.103.

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A new configuration of a hybrid system for cooling electronics using a Vortex Tube is presented. The optimization of the geometry and functional parameters is based on the assumption that the thermal interaction between the moist air stream and the heat-generating electronic board, and the phase change of liquid water vaporization occurs simultaneously. The first step of this analysis is focused on the optimal geometry of the system, while the second step identifies the Vortex Tube regime that maximizes its coefficient of performance. The cooling below the adiabatic air saturation temperature and the increase of moisture transport explain the high performance of the new device. Our results shed some light on the practical procedure for the optimal configuration of the new system.

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Rui, Huang, Zhou Kang, Pengcheng Guo, and Ma Wei. "Investigation of Transcritical Carbon Dioxide Power Generation System Based on Vortex Tube." Energies 16, no. 9 (April 26, 2023): 3723. http://dx.doi.org/10.3390/en16093723.

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In this paper, a transcritical carbon dioxide power generation system based on a vortex tube is studied, which has the advantage of the self-condensation of carbon dioxide. The thermodynamic performance of the system was investigated by establishing a mathematical model. The results showed that under fundamental working conditions, the system could output a net power of 271.72 kW, and the thermal efficiency as well as the exergy efficiency of the system could reach 7.38% and 27.09%, respectively. Exergy analysis showed that the turbine had the greatest exergy loss among the system’s components, followed by the vortex tube, pump, heater and cooler. Parameter analysis showed that increasing the outlet pressure and inlet temperature of the vortex tube can improve the thermal efficiency and exergy efficiency of the system. In addition, the improvement in the turbine component’s efficiency is the most beneficial to the system’s performance, among which the turbine’s efficiency has the greatest impact. Carbon dioxide can be effectively liquified by expanding it in the vortex tube, and its liquefaction ratio increases with the decrease in the vortex tube’s inlet temperature and the increase in the vortex tube’s inlet pressure.

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BALAMURUGAN, PASUPATHY, and ANNAMALAI MANI. "NUMERICAL STUDIES ON VERTICAL TUBULAR GENERATOR IN VAPOR ABSORPTION REFRIGERATION SYSTEM." International Journal of Air-Conditioning and Refrigeration 19, no. 02 (June 2011): 121–29. http://dx.doi.org/10.1142/s2010132511000454.

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A model has been developed based on Colburn–Drew type formulation to analyze a vertical tube in tube stainless steel generator with forced convective boiling. Desorption of refrigerant vapor from refrigerant–absorbent solution takes place in the inner tube of the generator, when hot water through the annulus is used as heating medium. Simultaneous heat and mass transfer phenomena of desorption are described mathematically using the mass and energy balances, considering the heat and mass transfer resistances in liquid as well as vapor phases. Model equations are solved simultaneously by means of initial value problem solvers using explicit Runge–Kutta method with 4th order accuracy. A computer code has been developed in MATLAB to obtain the results. A parametric analysis has also been performed to study the effect of various parameters on the performance of the generator.

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Rattanongphisat, Waraporn. "Efficiency of Vortex Tube Enclosure Cooling." Applied Mechanics and Materials 666 (October 2014): 154–58. http://dx.doi.org/10.4028/www.scientific.net/amm.666.154.

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A vortex tube offers an alternative cooling with advantages of simplicity and compact. Using a natural refrigerant, a vortex tube enclosure cooling is environmentally benign. In this paper, the performance of a vortex tube enclosure cooling, VTEC, is investigated experimentally. The VTEC system comprises of the vortex tube cooling, an enclosure with a volume space of 0.045 m3, an air compressor, a compressed air storage tank and a compressed air line. The VTEC system is tested for its efficiency and cooling potential in the laboratory. An operating condition is controlled by a pressure regulator for an inlet air pressure of 3 bars, for energy saving, and a cold flow rate is adjusted by a needle valve near the hot exit of a vortex tube for the cold fraction between 0 and 1. Accordingly, the analysis of experimental data shows the maximum isentropic efficiency of the vortex tube enclosure cooling is 0.37 at the cold mass fraction of 0.45. Air temperature in the enclosure is about 13°C in average.

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Gill, Jatinder, and Jagdev Singh. "Experimental Analysis of R134a/LPG as Replacement of R134a in a Vapor-Compression Refrigeration System." International Journal of Air-Conditioning and Refrigeration 25, no. 02 (April 4, 2017): 1750015. http://dx.doi.org/10.1142/s2010132517500158.

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This paper presents an experimental analysis of a vapor compression refrigeration system (VCRS) using the mixture of R134a and LPG with mass fractions of 28:72 as an alternative to R134a. In this work, we compare the energy performance of both refrigerants, R134a/LPG (28:72) and R134a, in a monitored vapor compression refrigeration system under a wide range of experimental conditions. So, the System with R134a/LPG (28:72) was tested by varying the capillary tube length and refrigerant charge under experimental conditions. Performance comparisons of both the systems are made taking refrigerant R134a as baseline, and the results show that the compressor power consumption, compressor discharge temperature and pull down time obtained with R134a/LPG (28:72) of 118[Formula: see text]g and capillary tube length of 5.1 m in vapor compression refrigeration system are about 4.4% 2.4% and 5.3%, respectively, lower than that obtained with R134a in the studied range. Also, when using R134a/LPG (28:72), the system shows values of refrigeration capacity and COP are about 10.6% and 15.2% respectively, higher than those obtained using R134a, In conclusion, the mixing refrigerant R134a/LPG proposed in this study seems to be an appropriate long-term candidate to replace R134a as a new generation refrigerant of VCRS, because of its well environmentally acceptable properties and its favorable refrigeration performances.

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Zhai, Xiaowei, Yu Xu, Zhijin Yu, and Kai Wang. "Proposed liquid CO2 cycle refrigeration system for heat hazard control." MATEC Web of Conferences 240 (2018): 05038. http://dx.doi.org/10.1051/matecconf/201824005038.

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Liquid CO2 can absorb heat via phase change and generates cryogenic CO2 which can effectively solve the problem of thermal damage in the deep coal mining process. The CO2 cycle refrigeration device system is designed to effectively cool down the working surface of the mine in which CO2 is cyclically utilized. COMSOL Multiphysics simulation software is used to characterize the CO2 cycle refrigeration system in mine of the heat transfers process between CO2 and the air flow in tunnel. The results show that the reduction of steady air flow temperature reach at 8 °C in the tunnel by CO2 cycle refrigeration system before the air flow into work face. we analyzed the influence of main parameters on refrigeration system and gets the results:1) The refrigeration system get higher cooling efficiency of cryogenic CO2 when the ventilation velocity of local fan is increased, and the temperature of outlet CO2 and steady air flow in tunnel has increased; 2) Increasing the CO2 flow, the refrigeration effect of the system is enhanced obviously, but CO2 refrigeration capacity utilization ratio is reduced; 3) Increasing the length of helical tube would led to use CO2 refrigerating capacity more efficiently; 4) The cooling effect of the cooling system can be improved obviously by lowering the the CO2 cooling temperature.

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Sarkar, Jahar. "Performance improvement of double-tube gas cooler in CO2 refrigeration system using nanofluids." Thermal Science 19, no. 1 (2015): 109–18. http://dx.doi.org/10.2298/tsci120702121s.

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The theoretical analyses of the double-tube gas cooler in transcritical carbon dioxide refrigeration cycle have been performed to study the performance improvement of gas cooler as well as CO2 cycle using Al2O3, TiO2, CuO and Cu nanofluids as coolants. Effects of various operating parameters (nanofluid inlet temperature and mass flow rate, CO2 pressure and particle volume fraction) are studied as well. Use of nanofluid as coolant in double-tube gas cooler of CO2 cycle improves the gas cooler effectiveness, cooling capacity and COP without penalty of pumping power. The CO2 cycle yields best performance using Al2O3-H2O as a coolant in double-tube gas cooler followed by TiO2-H2O, CuO-H2O and Cu-H2O. The maximum cooling COP improvement of transcritical CO2 cycle for Al2O3-H2O is 25.4%, whereas that for TiO2-H2O is 23.8%, for CuO-H2O is 20.2% and for Cu-H2O is 16.2% for the given ranges of study. Study shows that the nanofluid may effectively use as coolant in double-tube gas cooler to improve the performance of transcritical CO2 refrigeration cycle.

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Wu, Zhi Jiang. "The Experiment on System Performance Comparing Analysis and Displacement between R1270 and R22." Applied Mechanics and Materials 799-800 (October 2015): 770–73. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.770.

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The refrigeration circle performance of air conditioning comparing analysis and displacement between R1270 and R22 is studied in this paper. In addition, the system performance optimization of R1270 refrigeration circle is discussed.The experimental results show that the smaller tube diameter of heat exchanger for R1270 system is easy to improve the energy efficiency ratio in the unimproved system.These results are important for theory and reality to research this type of air conditioning.

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Pinheiro Ferreira, Vitor, Micael Lima Conceição, and William Souza dos Santos. "EXPERIMENTAL EVALUATION OF A CASCADE REFRIGERATION SYSTEM USING R-134a AND R-404a." RECIMA21 - Revista Científica Multidisciplinar - ISSN 2675-6218 3, no. 2 (February 7, 2022): e321127. http://dx.doi.org/10.47820/recima21.v3i2.1127.

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Cascade refrigeration system is an attractive technology for low-temperature requirement, allowing operation under these conditions with positive suction pressures and a moderate condensation pressure at ambient temperature. This work describes a performance analysis of a cascade refrigeration prototype equipped with hermetic compressors working with R-134a and R-404a as refrigerants, thermally connected by a tube-in-tube-type cascade-condenser. Energy flows and performance parameters were evaluated under different evaporating temperature conditions of the low temperature cycle (LTC). The results showed an increase in energy efficiency ratio (EER) and coefficients of performance (COP) of cascade system as well as of each cycle with the increase of LTC evaporating temperature, even with a simultaneous increase of temperature difference in cascade-condenser.

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Sidney, Shaji, Rajendran Prabakaran, and Mohan Lal Dhasan. "Thermal analysis on optimizing the capillary tube length of a milk chiller using DC compressor operated with HFC-134a and environment-friendly HC-600a refrigerants." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 234, no. 4 (August 25, 2019): 297–307. http://dx.doi.org/10.1177/0954408919871385.

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In this work, the thermal analysis on optimizing the capillary tube lengths of a dual circuit refrigeration system was carried out experimentally. Two refrigeration circuits were individually operated using two DC powered compressors (HFC-134a and HC-600a) instead of conventional AC powered compressors. The capillary tube optimization was done to maximize the coefficient of performance and exergy efficiency. From the results, it was found that the power consumption and the refrigerant mass flow rate decreases with the increase of capillary tube length for both the HFC-134a and HC-600a circuits, while the refrigeration capacity and coefficient of performance increased up to the capillary tube length of 4.57 m and then decreased. The maximum refrigeration capacity, ice formed, power consumption, and coefficient of performance experienced in the HC-600a circuit were 9.65%, 19.03%, 3.53%, and 7.34% lower than those of the HFC-134a circuit at the optimum capillary tube length. It was also found that at the optimum capillary length, the COP was maximum for the HFC-134a circuit while the exergy efficiency was maximum for the HC-600a circuit. The exergy efficiency of the HC-600a circuit was 11.13% higher than that of the HFC-134a circuit. At the optimum capillary tube length, the total equivalent warming impact values of the HFC-134a and HC-600a circuits were 961.13 kg CO2-eq and 785.77 kg CO2-eq, respectively.

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Pan, Hua Chen, and Shu Li Hong. "Improving the Efficiency of a Hydro-Turbine System by Vortex Generators." Advanced Materials Research 354-355 (October 2011): 636–41. http://dx.doi.org/10.4028/www.scientific.net/amr.354-355.636.

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This paper studies the effect of vortex generators on hydro-turbine working performances. The study was carried out on a hydro-turbine system provided by Waterpumps Oy, Finland. First, the performance of the hydro-turbine system was analyzed with a CFD solver under different working conditions. Then, the hydro-turbine performance was examined with several vortex generators installed uniformly on the inside wall of the draft tube near its inlet. The turbine system’s efficiencies were compared for cases with and without vortex generators. Results show that turbine performs better when there are vortex generators installed in the draft tube of which the pressure recovery factor is much higher.

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Coumaressin, T., K. Palaniradja, and K. Velmurugan. "Optimize the Evaporating Heat Transfer Coefficient of Refrigeration System Using Nano Fluid." Applied Mechanics and Materials 592-594 (July 2014): 951–55. http://dx.doi.org/10.4028/www.scientific.net/amm.592-594.951.

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Improving heat transfer characteristics in refrigeration and air conditioning systems has been intensively studied by many investigators. In the present work the effect of using CuO-R134a in the vapour compression system on the evaporating heat transfer coefficient is investigated by CFD heat transfer analysis using the FLUENT software. An experimental test rig is designed for this purpose. The test section is a horizontal tube in the tube heat exchanger made from copper. The refrigerant is evaporated inside an inner copper tube and the heat load is provided from hot water that passing in an annulus surrounding the inner tube. Heat transfer coefficients were evaluated using FLUENT for heat flux ranged from 10 to 40 kW/m2, using nanoCuO concentrations ranged from 0.05 to 1% and particle size from 15 to 70 nm. The measurements indicated that for a certain nanoconcentration as heat flux or mass flux increases the evaporating heat transfer coefficient increases and also that the evaporating heat transfer coefficient increases with increasing nanoCuO concentrations up to certain value then decreases. The obtained evaporating heat transfer coefficient result have been optimized at its maximum value for the best CuOnano particles concentration in R134a refrigerant.

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Belov, G. O., S. S. Dostovalova, E. О. Barbonov, D. A. Uglanov, P. A. Chertykovtsev, and R. A. Panshin. "The Vortex Aircooler System for Cutting Materials in Aerospace Industry." MATEC Web of Conferences 179 (2018): 02007. http://dx.doi.org/10.1051/matecconf/201817902007.

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In aerospace industry there is a situation, when it is not possible to use liquid cooling of cutting zone, because we have special material or special construction. How often in that case used air fluent, but it has some problems with life cycle tools, quality and cutting time. For solving these problems was use the vortex effect, it was open less than one hundred years ago. The unit for making vortex effect is could vortex tube. It was done the design the vortex tube of air cooler system for cutting using some researching [1-5]. Some experimental dates gave verification. The construction was made by metal materials and now is using on JSC «Salut», Samara..

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Reddy, B. N. C. Mohan, J. A. Sandeep kumar, and A. V. Hari Babu. "Performance Analysis of Alternative Refrigents Inside Capillary Tube of Refrigeration System." International Journal of Mechanical Engineering 4, no. 12 (December 25, 2017): 8–21. http://dx.doi.org/10.14445/23488360/ijme-v4i12p103.

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Traipattanakul, Bhawat, Jessadaporn Krongsinpinyo, Thanapol Lupkim, Patiya Pluemchit, and Yanisa Wunvisut. "Study of a Thermoacoustic Refrigeration System with a Spiral Rubber Stack." IOP Conference Series: Earth and Environmental Science 1050, no. 1 (July 1, 2022): 012016. http://dx.doi.org/10.1088/1755-1315/1050/1/012016.

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Abstract Thermoacoustic refrigeration technology converting sound energy into thermal energy offers environmental benefits including zero risks of ozone depletion or global warming potential due to the absence of hazardous refrigerants in the process. This study aims to investigate the effects of a spiral rubber stack on the cooling performance of a thermoacoustic refrigeration system made from an acrylic resonator tube. Air is used as a working gas. The results show that as time progresses, the temperature on the hot side of the stack increases, while that on the cold side of the stack reduces, leading to an increase in temperature difference across the stack. The findings of this study can potentially further expand knowledge and scientific experimental data in the field of thermoacoustic refrigeration.

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Joy, J., M. Raisee, and M. J. Cervantes. "Draft tube guide vane system to mitigate pressure pulsations." IOP Conference Series: Earth and Environmental Science 1079, no. 1 (September 1, 2022): 012048. http://dx.doi.org/10.1088/1755-1315/1079/1/012048.

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Abstract The present study introduces the concept of mitigating pressure pulsations in a hydro-turbine draft tube. The concept refers to using an adjustable guide vane system in the draft tube. The adjustability relates to its ability to rotate around an axis. The test rig for the experimental study is a high-head Francis model turbine. Three sets of guide vanes are distributed evenly circumferentially in the draft tube. Each guide vanes consists of two hydrofoils. The upper hydrofoil can move around an axis. The lower hydrofoil is fixed. The turbine operating head for the experiments was 12 m. The operating condition considered is at part load, for Q/Q BEP = 0.71. The results indicate that using the guide vanes in the draft tube, the plunging mode of the rotating vortex rope becomes insignificant for nearly all upper hydrofoil configurations considered. The reduction in the rotating mode of the vortex rope is between 50% and 80%. The vortex rope frequency shifts from 0.307·f 0 and varies between 0.33·f 0 to 0.617·f 0 , which is a function of upper hydrofoil angles

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Ji, A. Min, Tian Tian, and Bo Ning Tang. "Study on Solar Energy for Pre-Cooling Technology of Fruit and Vegetable." Applied Mechanics and Materials 700 (December 2014): 37–41. http://dx.doi.org/10.4028/www.scientific.net/amm.700.37.

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This paper discusses the importance of per-cooling vegetable and fruit, establishes a mathematical model of the solar adsorption refrigeration system collector bed. It applies activated carbon - methanol as working pairs, takes solar vacuum tube－water cooled collector bed for refrigerating, adsorption temperature and adsorption rate versus time are calculated , draw the corresponding curve figure. Analyses solar adsorption refrigeration system performance and puts forward the improvement direction.

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Journal articles on the topic 'Vortex Tube - Refrigeration System'

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