某PHEV车型电池热管理系统的1D/3D耦合分析

1D/3D Coupled Analysis for Battery Pack Thermal Management System in a Plug-in Hybrid Vehicle

采用1D/3D耦合仿真的手段对某PHEV车型电池包热管理系统进行了研究。1D建模方法用于建立电芯的等效电路模型,模型用试验数据标定,能预测电芯的发热量,并为3D仿真提供输入。3D仿真能够计算电芯内部的温度分布,而温度会影响1D等效电路的模型参数,进而影响发热量,以这种方式建立了仿真模型的1D/3D双向耦合。利用此模型,以一组高温恶劣工况下实测电池电流和电池包进口处冷却液温度为边界条件进行了瞬态分析,并将冷却液出口水温仿真结果与试验数据进行对比,结果显示两者平均偏差在1℃以内,体现出较好的预测效果。研究结果还显示,电池包外表面空气对流传递的热量在总散热量的5%以内,对结果影响不大。研究证明1D/3D耦合仿真是新能源车型电池包开发过程中的有力工具。

The battery pack including the battery cells and the thermal management cooling jacket in a Changan plug-in hybrid vehicle(PHEV)was investigated with a 1D/3D coupled approach.The 1D equivalent circuit model(ECM)is established and validated for a battery cell and is used to predict the heat generation,which is applied in the 3D CFD analysis.The 3D analysis determines the temperature distribution inside the cell that affects the ECM parameters,which in turn affects the battery heat generation.In this way,a twoway coupling between 3D and 1D was achieved and the accuracy of both models was improved.The transient simulation was then performed under extreme working cycles,choosing the experimentally measured values of battery current and coolant temperature as boundary conditions.The comparison of the simulated coolant outlet temperature and the experimental data shows a satisfying result of average deviation within 1-degree Celsius.The convective heat transfer in airflow was proved to be insignificant as it is less than 5% of the overall heat dissipation.The proposed 1D/3D coupled method is a useful tool for the future development of PHEVs and EVs.