The baseline performance prediction model was validated with steady state physical test data of limiting ambient temperature (LAT) for motor inlet. The objective of this work was to develop a radiator fan speed based logic as a function of vehicle operating conditions, ambient conditions and traction motor inlet coolant temperature, to reduce the battery pack power consumption. A radiator and fan assembly is used to reject the heat absorbed by an ethylene glycol - water based coolant from the traction system components. traction motor, traction inverter and auxiliary inverter. This work focuses on building a vehicle level one dimensional (1D) traction cooling system (TCS) model which simulates the cooling performance of the traction system components viz. In reality, airflow over coolpack is highly non-uniform, but it is considered as uniform in 1D analysis, which results into favorable PTC performance. With consideration of all above phenomena, 1D CAE predicts the performance up to an accuracy of ~93% to 95%. Additionally, hot air recirculation and correction factor for engine bench test data are also considered while simulating the 1D model. Hence, air mass flow rates over coolpack predicted by 3D CFD at various test conditions are directly used as an input in the 1D model. This eliminates the need of modeling the coefficient of pressure (Cp), built-in resistance (BiR) and coolpack fan in the 1D model for simulating airflow, as the combined effect of underhood restrictions and upstream heat rejection is already considered during the 3D CFD analysis. As the vehicle program matures, with availability of component level geometrical and functional data, airflow over coolpack is predicted in 3D CFD considering all underhood restrictions (grill, heat exchangers, engine block, etc.) and upstream components heat rejection.
To evaluate the HVAC and PTC performance at vehicle concept stage, airflow over coolpack (condenser, intercooler and radiator) from benchmark or similar platform is considered. Vehicle Level Thermal Performance Prediction Accuracy Enhancement by Modeling Non-Uniform Airflow Over Coolpack in 1D In order to consider all thermal effects for the proposed optimal hybrid strategy all information from Kuli is used in a Co-Simulation framework within Matlab and consequently the Kuli model information also influences the decisions of the applied optimal hybrid operation controller.
Hence, within this work Kuli is used as thermal modelling environment which enables detailed modelling of each component.
Due to the fact that all powertrain subsystems are connected by the cooling system, especially this behavior and its influences on the whole powertrain has to be investigated in all details. Consequently there is a high interest to investigate the behavior of the different interacting components (E-Motor, ICE, battery…) already in simulation. As consequence of the increasing hybridization and electrification in the automotive industry and the large variation of different concepts, the complexity of the powertrain is significantly increasing.
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