Measurements and CFD Modeling of Temperatures in the Engine Compartment of a Hybrid Electric Vehicle

In this article the temperature distribution within the engine compartment of a hybrid electric vehicle is experimentally and numerically investigated. The aim of this study is to develop a simulation model that captures the thermal behaviour of the electrical components for different driving conditions. For the experimental part, temperature sensors are placed at various locations inside cooling hoses as well as on the hoses and on various components. Using the commercial computational fluid dynamics (CFD) software StarCCM+, a complete vehicle simulation is set up for the same model. A comparison between the measurements and the numerical results shows good results. The increase in cooling media temperature when passing through the CIDD (Combined Inverter and DC/DC converter) is determined with a 10\,\% deviation, also the CIDD surface temperatures are well predicted. For the Electric Rear Axle Drive (ERAD) the surface temperatures lie within the requested 5k interval for the majority of measurement points, especially on the exterior of the cooling channel around the electric machine