This paper solves the selecting calculation of three-port valve with theoretical method and gives the equations for computing the static characteristics of surface cooler, the pulsation of total flow of valve, and the actual adjustable range of valve.

• 本文用理论方法解决三通阀的选择计算,提出表冷器静特性、阀门总流量波动、阀的实际可调范围等计算公式。