一种以水为工质的两级喷射制冷系统回收汽车废热研究

摘要

以氟利昂类物质为工质、回收汽车废热的喷射制冷技术得到了较广泛的关注和研究。但是氟利昂类工质在发生器高温受热时存在比较高的热解风险，氟利昂往往也具有温室效应。水作为自然工质，热稳定性好，具有氟利昂工质无法比拟的环保优势。为此，根据水喷射制冷系统的实际应用经验以及车载空调系统的特性，提出一种以水为工质、使用 U 型管作为节流装置的风冷两级喷射制冷系统。通过建立系统的数学物理模型和数值模拟分析，比较了系统在不同工况下的性能。结果表明，新系统既可以有效地利用汽车发动机的废热，作为汽车空调系统也具有可行性。%Jet refrigeration technology with chlorofluorocarbon as working medium for recycling automotive waste heat is widely used. But there is pyrolysis risk when the temperature of generator is high. Chlorofluorocarbon has a greenhouse effect. Water as a natural refrigerant has heat stability and is better than chlorofluorocarbon. So according to the practical application experience of water jet refrigeration system and feature of vehicle air conditioning system, the paper puts an air cooled two -stage ejector refrigeration system making water as working medium and making a u-tube as throttling device. Through establishing systematic mathematical-physical model and taking numerical simulation analysis, it compares the system's function at different condition. The result shows that the new system can effectively recycle the waste heat of automobile engine, and is feasible as automotive air conditioning system.