Abstract
After a brief review of the existing formulae for the unsteady heat transfer in I.C. engine cylinders, a new approach is described. It is shown that the existing empirical heat transfer data of forced convective case for the flat plates or pipes can be used to predict the heat transfer. Experimental results obtained on a motored engine are presented which include the measurement of gas velocity, temperature, pressure and metal surface temperature to obtain the convective unsteady heat transfer through the engine cycle. The experimental results are compared with the empirical data on a flat plate and it is concluded that the agreement is within 20 per cent.