THE HEAT TRANSFER DURING THE COMPRESSION PROCESS IN AN INTERNAL COMBUSTION ENGINE

At the beginning of the compression process the fresh charge is at a lower temperature than the one of the inner walls of the combustion chamber. The heat transfer takes place from the inner walls to the working fluid. The temperature of the fresh charge rises during the compression process and at one moment equals the one of the walls. Further gas temperature continues to rise and heat transfer takes place from the working fluid to the walls. So compression is a complex process with variable polytropic exponent This paper proposes a model to calculate heat transfer during the compression process.