Abstract: “Modelling of heat transfer losses to the engine wall of diesel engine involves the employment of heat transfer correlations in quasi one-dimensional thermodynamic simulation. In this study, four common existing heat transfer correlations - Woshni, Sitkei and Ramaniah, Hohenberg and Assanis - are utilised in a quasi one-dimensional thermodynamic simulation. Results are compared with experimental data from existing literature. The results indicate that Woshni’s correlation shows the best results as it includes a parameter that characterize the bore size of combustion chamber, while others exclude it. Attempt has been made to improve Woschni’s correlation by altering value of constants and power values in the velocity and temperature variables, in order to reduce the error from the experimental results. This finding reveals the current heat transfer correlations have inadequate representation of gas flow characteristics in the correlation especially in the near wall region, where velocity”

Keywords: convective heat transfer, correlation, modelling, compression- ignition engine