客车空调平行流蒸发器研制

对用于客车的顶部安装的空调中使用的平行流蒸发器进行了研究设计和实验验证。通过建立仿真模型模拟平行流蒸发器的换热能力,调整翅片参数优化结果,并制作了两组样件,对冷凝水、分液等问题进行实验验证和对比。实验结果表明,优化参数的百叶窗翅片在实验中几乎未见冷凝水沉积,同时分液的流路数为4分路的分液均匀性优于8分路,换热效果比8分路高11.2%。新设计的百叶窗翅片平行流蒸发器基本解决了冷凝水排除和两相流分液两大研究难点,体积较原来减少了57.6%,重量减轻了38%,充注量降低了10.5%,换热能力达到行业要求,从而达到取代旧式翅片管式蒸发器的目的。

Development of Micro-channel Evaporators for Bus Air Conditioner

Parallel flow evaporator with louver fins for roof top bus air conditioner was designed to replace the fin-and-tube evaporators. The capacity of parallel flow evaporator was simulated and the fin parameters were optimized by the established simulation model. Two sets of samples were experimentally investigated to verify the simulation results. The experiment results show that little condensate water was seen during the experiments, and the evaporator with 4 flow paths is of better homogeneity in refrigerant distribution and 11.2% higher in heat transfer than that with 8 flow paths. The newly designed evaporator is 38% lighter, 57.6% less volume and 10.5% less refrigerant charge than the traditional fin-and-tube evaporator, and almost solved the two serious problems of the application of parallel flow evaporator in bus, i.e., the removal of condensate water and the uniform distribution of two-phase-flow refrigerant, which indicates that the newly designed evaporator has reached the requirement of industry and can be used to replace the traditional fin-and-tube evaporator.