Abstract: Since only 25% ~ 35% of the heat generated by the combustion of the common automobile engine fuel is converted into effective output work, according to the characteristics of the waste heat of the engine, water is selected as the working medium to study how to avoid the phenomenon of wet liquid impacting the expander and realize the control of waste heat recovery system. Through the Rankine cycle principle, the evaporator superheat control is used to optimize the waste heat recovery system. In order to improve the waste heat recovery cycle efficiency, the solenoid valve control is added to control the speed of the working medium pump and the pressure of the evaporator, which can avoid the liquid collision of the expander. The overheating stability is effectively controlled and the cycle efficiency is improved.

Key words: Engine waste heat; Rankine cycle; Waste heat recovery; Cycle efficiency; Thermal cycle

摘要： 由于常用汽车发动机燃料燃烧产生的热量中只有 25%～35%转化为有效输出功，根据 发动机废热的特性，选择水作为工作介质，研究如何避免湿液冲击膨胀机的现象，实现废热 回收系统的控制。通过朗肯循环原理，蒸发器过热度控制用于优化余热回收系统，为提高余 热回收循环效率，增加了电磁阀控制，用于控制工质泵的转速和蒸发器的压力，可避免膨胀 机液体碰撞，过热稳定性得到有效控制，提高了循环效率。

关键词: 发动机废热；郎肯循环；废热回收；循环效率；热力循环