Real-time friction torque estimation on a diesel engine using the crankshaft speed fluctuation

Abstract

Under the pressure of stricter regulations on pollutant emissions and the desire of users for lower fuel consumption and more comfortable driving, engine control based on torque has been developed. To provide an accurate estimate of 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 is based on a combination of the dynamic model of the crankshaft and the thermodynamic model. The total instantaneous friction torque is determined using the instantaneous measurements or numerical predictions of the gas pressure in the combustion chamber, the rotational speed of the crankshaft and the load torque. The experimental data and the numerical simulation results were compared. The comparison between the different variables shows a good agreement between the simulation and the experimental results.

Total loss torque waveform estimation for a turbocharged diesel engine

“…The sum of the friction torque and load torque (including auxiliary) is called the total loss torque and constitutes the target to be reached. The equation (1) indicates that the total loss torque evaluation amounts the estimation of the in-cylinder pressure because the total torque (𝐽𝜃 ̈) and the mass torque 𝑇 𝑚 (𝜃, 𝜃 , 𝜃 ) are easy to determine them, where only the geometry, the moving masses and the kinematic of the engine are occurring (see the reference [11]):…”