Abstract
Keywords:Engine Modelling, Thermal management, Cooling, Combustion, Heat losses
The replacement of the "traditional" water pump driven by the crankshaft with an electrical one used to hold the cylinder head temperature below 150°C has shown high potential for fuel economy benefits. To assess such a strategy, a global thermal model was built from combustion to natural convection between the engine and the ambiance. With this kind of model, the impact of cooling strategies on indicated and mechanical efficiency can be assessed. This paper shows how the model was developed (thermodynamic model, nodal models of oil circuit, coolant circuit and engine parts), validated on the 1.9l HDI PSA engine and used to assess cooling strategies. The results show how the coolant mass flow can be significantly reduced and indicate the efficiency increase that can be expected from such a strategy.