Coupled Engine/Cooling System Simulation and its Application to Engine Warm-up

Coupled system modeling is increasingly advantageous as the consideration for vehicle system interactions intensifies. Significant interactions can occur between an engine and cooling system. Vehicle cooling systems can be coupled to the vehicle powertrain in many locations, including the cylinder structure, oil cooler, mechanical coolant pump, mechanical fan, EGR cooler, and charge-air-cooler. To enable the analysis of coupled systems, a linking capability was added to a cooling system simulation tool, GT-COOL, to tie it into an engine simulation tool. The paper describes the linkage methodology and its application.

This coupled simulation was applied to the study of a new concept, where the engine exhaust back pressure (and thus engine load) was artificially increased, in order to speed up the engine warm-up. The simulation was used to predict the effect of this concept on the rate of warm-up of the coolant and of the cylinder structure.