The Experts below are selected from a list of 1617 Experts worldwide ranked by ideXlab platform
Xiaolin Wang - One of the best experts on this subject based on the ideXlab platform.
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A Bench Evaluation Test for Refrigeration Oils in a Refrigeration System Using a Screw Compressor
Applied Sciences, 2019Co-Authors: Weifeng Wu, Liangwei Yang, Zhao Zhang, Xiaolin Wang, Quanke FengAbstract:Refrigeration oil has a large effect on the performance of refrigeration systems. However, the physical and chemical indexes of fresh refrigeration oils often fail to reflect the actual operating characteristics, especially with respect to the degradation of refrigeration oils. In this paper, a bench evaluation test of refrigeration oils was carried out to investigate the degradation of synthetic refrigeration oils used with the refrigerant R134a, in a purpose-built, full-scale refrigeration system utilizing a Screw Compressor. To accelerate the degradation process of the refrigeration oil, the discharge temperature at the exit of the Compressor was turned to a high level. Comparison tests of a mature refrigeration oil type A and a newly developed oil type B were performed under the same working conditions with 500 h of operating time. The performance of the Screw Compressor and refrigeration system was analyzed. The abrasion of the Screw rotors and carbon deposition at the discharge port was investigated. Results showed that the bench evaluation test successfully predicted the degradation process of the refrigeration oils. The evolution analysis of the refrigeration oil viscosity and acid value during the bench evaluation test indicated that 15% of the physical and chemical indexes for refrigeration oil drain were too strict. Research work in this paper showed a more practical method to evaluate the performance of refrigeration oils through the bench evaluation test.
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Theoretical study of two-stage water vapor compression systems
Applied Thermal Engineering, 2019Co-Authors: Jiubing Shen, Guozeng Feng, Ziwen Xing, Xiaolin WangAbstract:Water vapor compression is a key technology that greatly affects system performance in heat pump and mechanical vapor compression/recompression applications. In this paper, two-stage water vapor compression methods (cascaded centrifugal Compressors and combined centrifugal and twin-Screw Compressors) were proposed and studied to deal with the water compression process with large suction volume flow rates and high compression pressure ratios. A mathematical model was developed, and the thermal characteristics, achievable volume flow rate and saturation temperature rise of the two water compression systems were presented. The two-stage compression process using cascaded centrifugal Compressors was found to be better for applications with total saturation temperature rise lower than 40 °C. The two-stage compression process using combined centrifugal and twin-Screw Compressors was found to satisfy applications with a saturation temperature rise as high as 80 °C. Further investigation showed that the second method could deliver a suction volume flow rate of 1418 m3/min with a suction vapor temperature of 50 °C using a current market-available twin-Screw Compressor with a capacity of 600 m3/min. The performance of the combined systems was largely affected by the pressure ratio and the Compressor efficiency, system suction vapor temperature, and total vapor saturation temperature rise. The analyses showed that the combined system had high energy efficiency above 3.4 under all studied working conditions.
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performance evaluation of a capacity regulated high temperature heat pump for waste heat recovery in dyeing industry
Applied Thermal Engineering, 2016Co-Authors: Xiaokun Wu, Ziwen Xing, Zhilong He, Xiaolin Wang, Wenqing ChenAbstract:In this paper, a capacity-regulated high temperature heat pump (HTHP) system using a twin-Screw Compressor was designed to recover waste heat in dyeing industry. The performance of the HTHP system was investigated under an on-site skein dyeing process condition. Results showed that the HTHP system could effectively utilize the waste heat at different temperatures to provide the energy required by the dyeing process. The heating capacity of the HTHP system could be well controlled to achieve the desired dyeing liquid temperature rising rate between 0.6 and 2.5 °C/min during different heating processes. The on-site testing results further demonstrated that the HTHP system could be reliably operated to heat the dyeing liquid temperature up to 95 °C with an average system COP of 4.2 during the entire heating process. Economic analysis indicated that the HTHP system could save about 47% of the operating cost in comparison to the traditional steam heating.
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Development of a water-injected twin-Screw Compressor for mechanical vapor compression desalination systems
Applied Thermal Engineering, 2016Co-Authors: Jiubing Shen, Ziwen Xing, Zhilong He, Kai Zhang, Xiaolin WangAbstract:The water-injected twin-Screw Compressor is a key component in the mechanical vapor compression (MVC) desalination system, which is a promising technology for small and medium scale water production. This paper presents an experimental study on a water-injected twin-Screw Compressor. A prototype is developed and applied in a 50 m3/day double-effect MVC system. The effect of important parameters (including Compressor rotation speed, water injection flow rate and Compressor inlet temperature) on the Compressor performance is experimentally investigated. It is found that the volumetric flow rate and power consumption of the Compressor increases almost linearly with the rise in Compressor rotation speed. Results also show that the Compressor inlet temperature only affects the power consumption of the twin-Screw Compressor. It has minor effect on the volumetric flow rate, and volumetric and isentropic efficiencies of the Compressor. Study further shows that water injection substantially reduces the Compressor discharge temperature. As the water injection flow rate increases, the vapor compression process more closely approaches saturation vapor compression and hence the isentropic efficiency of the twin-Screw Compressor increases. The analyses demonstrate that the water-injected twin-Screw Compressor can be reliably operated in the MVC system with satisfactory system performance.
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analysis of a single effect mechanical vapor compression desalination system using water injected twin Screw Compressors
Desalination, 2014Co-Authors: Jiubing Shen, Ziwen Xing, Xiaolin Wang, Zhilong HeAbstract:Abstract The mechanical vapor compression (MVC) desalination system is very attractive and competitive for small and medium scale water production. This paper presents a comprehensive analysis of a single-effect MVC desalination system using water injected twin Screw Compressors. The operational characteristics of the twin Screw Compressor including inlet volume flow rate, Compressor pressure ratio, and mass fraction of injected water are investigated. The specific power consumption and the specific heat transfer area of the MVC system are then analyzed based on these characteristics. The results are comparable with data reported in literature for similar single-effect MVC desalination systems. Further comparison is performed for a single-effect MVC system using a twin Screw Compressor with/without water injection. The results demonstrate that the single-effect MVC desalination system using water injected twin Screw Compressor is a very promising technology for water production capacities less than 600 m3/d. It also shows that the temperature difference between boiling vapor and compressed vapor at Compressor exit can be as high as 10 °C.
Ziwen Xing - One of the best experts on this subject based on the ideXlab platform.
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Theoretical study of two-stage water vapor compression systems
Applied Thermal Engineering, 2019Co-Authors: Jiubing Shen, Guozeng Feng, Ziwen Xing, Xiaolin WangAbstract:Water vapor compression is a key technology that greatly affects system performance in heat pump and mechanical vapor compression/recompression applications. In this paper, two-stage water vapor compression methods (cascaded centrifugal Compressors and combined centrifugal and twin-Screw Compressors) were proposed and studied to deal with the water compression process with large suction volume flow rates and high compression pressure ratios. A mathematical model was developed, and the thermal characteristics, achievable volume flow rate and saturation temperature rise of the two water compression systems were presented. The two-stage compression process using cascaded centrifugal Compressors was found to be better for applications with total saturation temperature rise lower than 40 °C. The two-stage compression process using combined centrifugal and twin-Screw Compressors was found to satisfy applications with a saturation temperature rise as high as 80 °C. Further investigation showed that the second method could deliver a suction volume flow rate of 1418 m3/min with a suction vapor temperature of 50 °C using a current market-available twin-Screw Compressor with a capacity of 600 m3/min. The performance of the combined systems was largely affected by the pressure ratio and the Compressor efficiency, system suction vapor temperature, and total vapor saturation temperature rise. The analyses showed that the combined system had high energy efficiency above 3.4 under all studied working conditions.
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performance evaluation of a capacity regulated high temperature heat pump for waste heat recovery in dyeing industry
Applied Thermal Engineering, 2016Co-Authors: Xiaokun Wu, Ziwen Xing, Zhilong He, Xiaolin Wang, Wenqing ChenAbstract:In this paper, a capacity-regulated high temperature heat pump (HTHP) system using a twin-Screw Compressor was designed to recover waste heat in dyeing industry. The performance of the HTHP system was investigated under an on-site skein dyeing process condition. Results showed that the HTHP system could effectively utilize the waste heat at different temperatures to provide the energy required by the dyeing process. The heating capacity of the HTHP system could be well controlled to achieve the desired dyeing liquid temperature rising rate between 0.6 and 2.5 °C/min during different heating processes. The on-site testing results further demonstrated that the HTHP system could be reliably operated to heat the dyeing liquid temperature up to 95 °C with an average system COP of 4.2 during the entire heating process. Economic analysis indicated that the HTHP system could save about 47% of the operating cost in comparison to the traditional steam heating.
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Development of a water-injected twin-Screw Compressor for mechanical vapor compression desalination systems
Applied Thermal Engineering, 2016Co-Authors: Jiubing Shen, Ziwen Xing, Zhilong He, Kai Zhang, Xiaolin WangAbstract:The water-injected twin-Screw Compressor is a key component in the mechanical vapor compression (MVC) desalination system, which is a promising technology for small and medium scale water production. This paper presents an experimental study on a water-injected twin-Screw Compressor. A prototype is developed and applied in a 50 m3/day double-effect MVC system. The effect of important parameters (including Compressor rotation speed, water injection flow rate and Compressor inlet temperature) on the Compressor performance is experimentally investigated. It is found that the volumetric flow rate and power consumption of the Compressor increases almost linearly with the rise in Compressor rotation speed. Results also show that the Compressor inlet temperature only affects the power consumption of the twin-Screw Compressor. It has minor effect on the volumetric flow rate, and volumetric and isentropic efficiencies of the Compressor. Study further shows that water injection substantially reduces the Compressor discharge temperature. As the water injection flow rate increases, the vapor compression process more closely approaches saturation vapor compression and hence the isentropic efficiency of the twin-Screw Compressor increases. The analyses demonstrate that the water-injected twin-Screw Compressor can be reliably operated in the MVC system with satisfactory system performance.
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analysis of a single effect mechanical vapor compression desalination system using water injected twin Screw Compressors
Desalination, 2014Co-Authors: Jiubing Shen, Ziwen Xing, Xiaolin Wang, Zhilong HeAbstract:Abstract The mechanical vapor compression (MVC) desalination system is very attractive and competitive for small and medium scale water production. This paper presents a comprehensive analysis of a single-effect MVC desalination system using water injected twin Screw Compressors. The operational characteristics of the twin Screw Compressor including inlet volume flow rate, Compressor pressure ratio, and mass fraction of injected water are investigated. The specific power consumption and the specific heat transfer area of the MVC system are then analyzed based on these characteristics. The results are comparable with data reported in literature for similar single-effect MVC desalination systems. Further comparison is performed for a single-effect MVC system using a twin Screw Compressor with/without water injection. The results demonstrate that the single-effect MVC desalination system using water injected twin Screw Compressor is a very promising technology for water production capacities less than 600 m3/d. It also shows that the temperature difference between boiling vapor and compressed vapor at Compressor exit can be as high as 10 °C.
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experimental study on p v indicator diagrams of twin Screw refrigeration Compressor with economizer
Applied Thermal Engineering, 2004Co-Authors: Huagen Wu, Xueyuan Peng, Ziwen XingAbstract:This paper presents the experimental investigation on the effects of the superfeed pressure together with economizer type on the performance of the twin-Screw refrigeration Compressor by means of the indicator diagram. With a pressure sensor embedded into the groove at the root of the female rotor on the discharge side, the pressure within the working chamber of a semi-hermetic twin-Screw Compressor with an economizer is recorded and then transformed into the indicator diagram. The results thus obtained are utilized to investigate the thermodynamic process of the Compressor. It is shown that the Compressor with an economizer has higher pressure during almost the whole compression process than without an economizer, resulting in the increase in the indicated power. Under different superfeed pressures, the pressure within the compression experiences different changes. This results in an optimal superfeed pressure for maximized Compressor efficiency, which can be identified from the calculated Compressor efficiency based on the indicator diagrams. It is also found that the pressure has a rapid increase at the beginning of superfeed process, and then a slow rise even a slight drop at the end of superfeed process, which is caused by the dynamic effect during superfeed process. Furthermore, if the superfeed pressure keeps the same, the pressure during compression in the Compressor with the heat exchanger economizer is slightly higher than with the flash tank economizer, due to the higher temperature of superfeed refrigerant gas in the former case.
Zhilong He - One of the best experts on this subject based on the ideXlab platform.
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performance evaluation of a capacity regulated high temperature heat pump for waste heat recovery in dyeing industry
Applied Thermal Engineering, 2016Co-Authors: Xiaokun Wu, Ziwen Xing, Zhilong He, Xiaolin Wang, Wenqing ChenAbstract:In this paper, a capacity-regulated high temperature heat pump (HTHP) system using a twin-Screw Compressor was designed to recover waste heat in dyeing industry. The performance of the HTHP system was investigated under an on-site skein dyeing process condition. Results showed that the HTHP system could effectively utilize the waste heat at different temperatures to provide the energy required by the dyeing process. The heating capacity of the HTHP system could be well controlled to achieve the desired dyeing liquid temperature rising rate between 0.6 and 2.5 °C/min during different heating processes. The on-site testing results further demonstrated that the HTHP system could be reliably operated to heat the dyeing liquid temperature up to 95 °C with an average system COP of 4.2 during the entire heating process. Economic analysis indicated that the HTHP system could save about 47% of the operating cost in comparison to the traditional steam heating.
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Development of a water-injected twin-Screw Compressor for mechanical vapor compression desalination systems
Applied Thermal Engineering, 2016Co-Authors: Jiubing Shen, Ziwen Xing, Zhilong He, Kai Zhang, Xiaolin WangAbstract:The water-injected twin-Screw Compressor is a key component in the mechanical vapor compression (MVC) desalination system, which is a promising technology for small and medium scale water production. This paper presents an experimental study on a water-injected twin-Screw Compressor. A prototype is developed and applied in a 50 m3/day double-effect MVC system. The effect of important parameters (including Compressor rotation speed, water injection flow rate and Compressor inlet temperature) on the Compressor performance is experimentally investigated. It is found that the volumetric flow rate and power consumption of the Compressor increases almost linearly with the rise in Compressor rotation speed. Results also show that the Compressor inlet temperature only affects the power consumption of the twin-Screw Compressor. It has minor effect on the volumetric flow rate, and volumetric and isentropic efficiencies of the Compressor. Study further shows that water injection substantially reduces the Compressor discharge temperature. As the water injection flow rate increases, the vapor compression process more closely approaches saturation vapor compression and hence the isentropic efficiency of the twin-Screw Compressor increases. The analyses demonstrate that the water-injected twin-Screw Compressor can be reliably operated in the MVC system with satisfactory system performance.
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analysis of a single effect mechanical vapor compression desalination system using water injected twin Screw Compressors
Desalination, 2014Co-Authors: Jiubing Shen, Ziwen Xing, Xiaolin Wang, Zhilong HeAbstract:Abstract The mechanical vapor compression (MVC) desalination system is very attractive and competitive for small and medium scale water production. This paper presents a comprehensive analysis of a single-effect MVC desalination system using water injected twin Screw Compressors. The operational characteristics of the twin Screw Compressor including inlet volume flow rate, Compressor pressure ratio, and mass fraction of injected water are investigated. The specific power consumption and the specific heat transfer area of the MVC system are then analyzed based on these characteristics. The results are comparable with data reported in literature for similar single-effect MVC desalination systems. Further comparison is performed for a single-effect MVC system using a twin Screw Compressor with/without water injection. The results demonstrate that the single-effect MVC desalination system using water injected twin Screw Compressor is a very promising technology for water production capacities less than 600 m3/d. It also shows that the temperature difference between boiling vapor and compressed vapor at Compressor exit can be as high as 10 °C.
Jiubing Shen - One of the best experts on this subject based on the ideXlab platform.
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Theoretical study of two-stage water vapor compression systems
Applied Thermal Engineering, 2019Co-Authors: Jiubing Shen, Guozeng Feng, Ziwen Xing, Xiaolin WangAbstract:Water vapor compression is a key technology that greatly affects system performance in heat pump and mechanical vapor compression/recompression applications. In this paper, two-stage water vapor compression methods (cascaded centrifugal Compressors and combined centrifugal and twin-Screw Compressors) were proposed and studied to deal with the water compression process with large suction volume flow rates and high compression pressure ratios. A mathematical model was developed, and the thermal characteristics, achievable volume flow rate and saturation temperature rise of the two water compression systems were presented. The two-stage compression process using cascaded centrifugal Compressors was found to be better for applications with total saturation temperature rise lower than 40 °C. The two-stage compression process using combined centrifugal and twin-Screw Compressors was found to satisfy applications with a saturation temperature rise as high as 80 °C. Further investigation showed that the second method could deliver a suction volume flow rate of 1418 m3/min with a suction vapor temperature of 50 °C using a current market-available twin-Screw Compressor with a capacity of 600 m3/min. The performance of the combined systems was largely affected by the pressure ratio and the Compressor efficiency, system suction vapor temperature, and total vapor saturation temperature rise. The analyses showed that the combined system had high energy efficiency above 3.4 under all studied working conditions.
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Development of a water-injected twin-Screw Compressor for mechanical vapor compression desalination systems
Applied Thermal Engineering, 2016Co-Authors: Jiubing Shen, Ziwen Xing, Zhilong He, Kai Zhang, Xiaolin WangAbstract:The water-injected twin-Screw Compressor is a key component in the mechanical vapor compression (MVC) desalination system, which is a promising technology for small and medium scale water production. This paper presents an experimental study on a water-injected twin-Screw Compressor. A prototype is developed and applied in a 50 m3/day double-effect MVC system. The effect of important parameters (including Compressor rotation speed, water injection flow rate and Compressor inlet temperature) on the Compressor performance is experimentally investigated. It is found that the volumetric flow rate and power consumption of the Compressor increases almost linearly with the rise in Compressor rotation speed. Results also show that the Compressor inlet temperature only affects the power consumption of the twin-Screw Compressor. It has minor effect on the volumetric flow rate, and volumetric and isentropic efficiencies of the Compressor. Study further shows that water injection substantially reduces the Compressor discharge temperature. As the water injection flow rate increases, the vapor compression process more closely approaches saturation vapor compression and hence the isentropic efficiency of the twin-Screw Compressor increases. The analyses demonstrate that the water-injected twin-Screw Compressor can be reliably operated in the MVC system with satisfactory system performance.
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analysis of a single effect mechanical vapor compression desalination system using water injected twin Screw Compressors
Desalination, 2014Co-Authors: Jiubing Shen, Ziwen Xing, Xiaolin Wang, Zhilong HeAbstract:Abstract The mechanical vapor compression (MVC) desalination system is very attractive and competitive for small and medium scale water production. This paper presents a comprehensive analysis of a single-effect MVC desalination system using water injected twin Screw Compressors. The operational characteristics of the twin Screw Compressor including inlet volume flow rate, Compressor pressure ratio, and mass fraction of injected water are investigated. The specific power consumption and the specific heat transfer area of the MVC system are then analyzed based on these characteristics. The results are comparable with data reported in literature for similar single-effect MVC desalination systems. Further comparison is performed for a single-effect MVC system using a twin Screw Compressor with/without water injection. The results demonstrate that the single-effect MVC desalination system using water injected twin Screw Compressor is a very promising technology for water production capacities less than 600 m3/d. It also shows that the temperature difference between boiling vapor and compressed vapor at Compressor exit can be as high as 10 °C.
Chunlu Zhang - One of the best experts on this subject based on the ideXlab platform.
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dynamic simulation of air to water dual mode heat pump with Screw Compressor
Applied Thermal Engineering, 2003Co-Authors: Long Fu, Guoliang Ding, Chunlu ZhangAbstract:Abstract A dynamic model of air-to-water dual-mode heat pump with Screw Compressor is presented here. The high-pressure and low-pressure segments are divided into three control volumes, including the refrigerant inside tube, the tube wall and the fluid outside tube that is water or air. Time dependent ordinary differential equations are obtained from the mass and energy balances for each control volume. As the Compressor, thermostatic expansion valve (TEV) body, and reversing valve have very small thermal inertias, steady-state models are applied for the compression, throttling, and leakage processes. The relationship between the temperature of the saturated liquid–vapor mixture in TEV’s bulb and the temperature of the refrigerant vapor at the evaporator exit is described with a time dependent ordinary differential equation. System simulation is finally carried out with ‘predictor–corrector’ and ‘adaptive integration step’ methods. Simulated results are in good agreement with the measured data, which lead to conclusion that the model can be used as a tool for the product development.
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dynamic simulation of air to water dual mode heat pump with Screw Compressor
Applied Thermal Engineering, 2003Co-Authors: Long Fu, Guoliang Ding, Chunlu ZhangAbstract:Abstract A dynamic model of air-to-water dual-mode heat pump with Screw Compressor is presented here. The high-pressure and low-pressure segments are divided into three control volumes, including the refrigerant inside tube, the tube wall and the fluid outside tube that is water or air. Time dependent ordinary differential equations are obtained from the mass and energy balances for each control volume. As the Compressor, thermostatic expansion valve (TEV) body, and reversing valve have very small thermal inertias, steady-state models are applied for the compression, throttling, and leakage processes. The relationship between the temperature of the saturated liquid–vapor mixture in TEV’s bulb and the temperature of the refrigerant vapor at the evaporator exit is described with a time dependent ordinary differential equation. System simulation is finally carried out with ‘predictor–corrector’ and ‘adaptive integration step’ methods. Simulated results are in good agreement with the measured data, which lead to conclusion that the model can be used as a tool for the product development.
