文档介绍:第 卷 第 期 合 肥 工 业 大 学 学 报 自 然 科 学 版
45 5 nfluence of node tempera-
ture difference on the performance coefficient of automobile air conditioning refrigeration system under
different evaporator outlet air temperature and condenser outlet air temperature.And the total heat
transfer area of parallel flow heat exchanger is optimized with the system performance coefficient per
unit heat transfer area as the objective function.The results show that for the selected refrigerants,
with the increase of the node temperature difference,the performance coefficient of the refrigeration
system decreases,the area of the heat exchanger decreases,and the objective function value first in-
creases and then decreases,suggesting that there is an optimal node temperature difference which
makes the best of the economic performance of the refrigeration system.Under the set operating con-
ditions,the optimal condenser node temperature differences of R245fa,R1234ze,R134aand R123are
4 ℃,4 ℃,6 ℃ and 4 ℃,respectively,and the optimal evaporator node temperature differences are
22℃,20℃,20℃ and 24℃,respectively.As for R134arefrigerant,when the outlet air tempera-
ture of evaporator is 15℃ and the outlet air temperature of condenser is 45℃,the performance coef-
ficient per unit heat transfer area is the largest.
Key w