A general model to evaluate mechanical losses and auxiliary energy consumption in reciprocating internal combustion engines

The increasingly stringent emissions regulations and the climatic change as consequence of green house gases emissions have moved the research interest towards the optimization of the internal combustion engine. Hence, the reduction of the energy losses of the engine sub-systems like friction and parasitic energy consumption are of especial interest. In this work, a model to determine the friction losses and the engine accessories energy consumption is developed based on parameters obtained in standard test benches. A description of the models to estimate friction in the piston assembly, bearings and valve train, and energy consumption of the coolant, oil and fuel pump is provided. Finally, a brief application to demonstrate the model potential in diagnosis and predictive applications is discussed.