Abstract:

The air conditioner of diesel vehicles consumes the fuel of engine, which reduces the economic benefits of diesel vehicles especially in areas with strong solar radiation. To solve this problem, a set of solid sorption vehicle air-conditioning system driven by the exhaust gas of engine is built. The system consists of two solid sorption beds filled with CaCl₂/MnCl₂/expanded natural graphite treated with sulphuric acid (ENG-TSA) composite sorbent, an evaporator, a condenser, a liquid storage tank, and valves. It uses ammonia as refrigerant. Natural wind cools the solid sorption bed and provides continuous cooling effect to the cabin, while the heating phase for generation is completed by exhaust gas. The system is simulated, and the refrigeration effect is tested by experiments. The simulation results show that the optimal cycle time of the system is 45 min, and theoretical average cooling power of the system can reach more than 3.5 kW, while the system COP is between 0.2 and 0.25. The experimental results show that the system can generate an average cooling capacity of 3 kW under the exhaust gas temperature of 230℃. Under the ambient temperature of 40℃, the average temperature difference of the system at the inlet and outlet of the evaporator is 6.5℃, and the average cooling capacity is 3.2 kW.

Key words: sorption refrigeration, diesel vehicles, engine exhaust, heat recovery, sorbents

摘要：

针对在高太阳辐射地区，柴油车驾驶室内使用车载空调会增加车辆发动机的耗油量、降低柴油车经济效益的问题，搭建了一套由发动机尾气余热驱动的吸附式车载空调系统。系统由填充有氯化钙/氯化锰/硫化膨胀石墨复合吸附剂的吸附床、蒸发器、冷凝器、储液罐和阀门组成，使用氨作为制冷剂，利用车辆在行驶时接触到的自然风为吸附床冷却，在发动机尾气余热的驱动下，为驾驶室内提供连续的制冷效果。结合仿真和实验测试，对所设计系统的制冷性能进行了分析，仿真结果表明，系统最优循环时间为45 min，系统的理论平均制冷功率可达3.5 kW以上，系统COP处于0.2~0.25之间。实验结果表明，在230℃的尾气温度条件下，系统能产生3 kW的平均制冷量。在40℃环境温度条件下，系统在蒸发器进出口处的平均温差为6.5℃，平均制冷量为3.2 kW。

关键词: 吸附式制冷, 柴油车, 尾气, 余热利用, 吸附剂