Heat transfer process in power system applications mainly refers to the gas in the cylinder through the combustion chamber wall and related parts pass the process of cooling medium, the heat it mainly includes the gas flow and combustion in cylinder, cylinder internal boundary layer heat transfer (gas and wall heat transfer), heated component of thermal load and thermal conductivity, cooling medium heat transfer, and a series of process. Because it is closely related to the working process of the power system, the lubrication cooling system and the structural strength design of components, the heat transfer and its thermal load will directly affect the dynamic performance, economy and reliability of the system. Therefore, the heat conduction of machining in the power system has always been an important field in the power system research.