SUMMARY
Under the pressure of stricter regulations on pollutant emissions, users seeking better fuel economy and better driving comfort, the control of the engine based on the torque were developed. To be able to provide an accurate estimate of the effective torque, friction losses must be modeled. The details of a model that predicts the total instantaneous friction torque for compression ignition engines are described. The model, based on a combination between the dynamic model of the crankshaft and the thermodynamic model. The total instantaneous friction torque is determined, via the instantaneous measurements or numerical predictions of the gas pressure in the combustion chamber, the speed of rotation of the crankshaft and load torque. The experimental data and the results of the numerical simulation have been compared. The comparison between the different variables shows a good agreement between the simulation and the experimental results.