Theoretical and experimental analysis of a new refrigerant mixture BY-3 was conducted based on a single-stage vapor compression refrigeration system. The water-water heat pump system used BY-3 to produce hot water whe...Theoretical and experimental analysis of a new refrigerant mixture BY-3 was conducted based on a single-stage vapor compression refrigeration system. The water-water heat pump system used BY-3 to produce hot water when the low temperature was 20 ℃. The following results were obtained: the highest temperature at the condenser outlet reached about 85 ℃; when the difference between the water temperatures at the condenser outlet and the evaporator inlet was less than 40 ℃, the coefficient of performance (COP) was larger than 4; when the difference reached 55 ℃, the COP still kept 3; the discharge temperature of BY-3 was lower than 100 ℃, and the refrigerant vapor pressure kept lower than 1.8 MPa. When the water temperature at the condenser outlet reached over 85 ℃, nearly a 5 ℃ superheating temperature was maintained.展开更多
The liquid molar volumes of nonazeotropic refrigerant mixtures(NARM), calculated with Peng Robinson (PR) equation, were compared with vapor-liquid equilibrium experimental data in this paper.Provided with coreaction c...The liquid molar volumes of nonazeotropic refrigerant mixtures(NARM), calculated with Peng Robinson (PR) equation, were compared with vapor-liquid equilibrium experimental data in this paper.Provided with coreaction coefficient kij, the discrepancies of liquid molar volume data for R22+R142b and R22+R142b using PR equation are 7.7% and 8.1%, respectively. When HBT (Hankinson-Brobst-Tholnson) equation was joined with PR equation, the deviations are reduced to less than 1.5% for both R22+R114 and R22+R142b.展开更多
Nucleate pool boiling heat transfer data of the HFC23/CFC13 system have been systematically measured in a wide range of pressures and heat fluxes. The experimental results are also compared with the measured data of R...Nucleate pool boiling heat transfer data of the HFC23/CFC13 system have been systematically measured in a wide range of pressures and heat fluxes. The experimental results are also compared with the measured data of R508A and R508B. It is found that the heat transfer coefficient of R503 （HFC23/CFC13=0.511/0.489） is higher than that of R508A and R508B. Furthermore, the measured data were compared with the predicted results with three well-known correlations. Correlation by Fujita and Tsutsui can provide acceptable results. Most of the data fall within ±20% of this correlation.展开更多
Cryosurgery is an effective way of curing many diseases including tumors and cancers. It can be applied using a variety of systems and cryogens. Cheap, convenient, reliable equipment still needs to be developed so tha...Cryosurgery is an effective way of curing many diseases including tumors and cancers. It can be applied using a variety of systems and cryogens. Cheap, convenient, reliable equipment still needs to be developed so that cryotherapy may be accepted by surgeons and hospitals. This paper presents a cryosurgery apparatus that utilizes an auto-cascade refrigeration system. Refrigerant mixture R50/R23/R600a was selected as the working fluid. The mixture composition was altered to achieve lower temperatures and higher capacity. The lowest temperature at the cryoprobe could be as low as -100℃, and 8 W refrigeration capacity could be obtained at -80 ℃. An ice ball of 11.6 mm diameter could be formed when the cryoprobe was immersed in a water bath at 37 ℃.展开更多
基金Supported by Major State Basic Research Development Program of China ("973" Program, No. 2009CB219907)the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT0936)
文摘Theoretical and experimental analysis of a new refrigerant mixture BY-3 was conducted based on a single-stage vapor compression refrigeration system. The water-water heat pump system used BY-3 to produce hot water when the low temperature was 20 ℃. The following results were obtained: the highest temperature at the condenser outlet reached about 85 ℃; when the difference between the water temperatures at the condenser outlet and the evaporator inlet was less than 40 ℃, the coefficient of performance (COP) was larger than 4; when the difference reached 55 ℃, the COP still kept 3; the discharge temperature of BY-3 was lower than 100 ℃, and the refrigerant vapor pressure kept lower than 1.8 MPa. When the water temperature at the condenser outlet reached over 85 ℃, nearly a 5 ℃ superheating temperature was maintained.
文摘The liquid molar volumes of nonazeotropic refrigerant mixtures(NARM), calculated with Peng Robinson (PR) equation, were compared with vapor-liquid equilibrium experimental data in this paper.Provided with coreaction coefficient kij, the discrepancies of liquid molar volume data for R22+R142b and R22+R142b using PR equation are 7.7% and 8.1%, respectively. When HBT (Hankinson-Brobst-Tholnson) equation was joined with PR equation, the deviations are reduced to less than 1.5% for both R22+R114 and R22+R142b.
基金This project is supported by the National Natural Science Foundation of China under the contract number of 50576102.
文摘Nucleate pool boiling heat transfer data of the HFC23/CFC13 system have been systematically measured in a wide range of pressures and heat fluxes. The experimental results are also compared with the measured data of R508A and R508B. It is found that the heat transfer coefficient of R503 （HFC23/CFC13=0.511/0.489） is higher than that of R508A and R508B. Furthermore, the measured data were compared with the predicted results with three well-known correlations. Correlation by Fujita and Tsutsui can provide acceptable results. Most of the data fall within ±20% of this correlation.
基金Project (No.50606032) supported by the National Natural Science Foundation of China
文摘Cryosurgery is an effective way of curing many diseases including tumors and cancers. It can be applied using a variety of systems and cryogens. Cheap, convenient, reliable equipment still needs to be developed so that cryotherapy may be accepted by surgeons and hospitals. This paper presents a cryosurgery apparatus that utilizes an auto-cascade refrigeration system. Refrigerant mixture R50/R23/R600a was selected as the working fluid. The mixture composition was altered to achieve lower temperatures and higher capacity. The lowest temperature at the cryoprobe could be as low as -100℃, and 8 W refrigeration capacity could be obtained at -80 ℃. An ice ball of 11.6 mm diameter could be formed when the cryoprobe was immersed in a water bath at 37 ℃.
