Abstract:

In electric vehicles, a battery thermal management system is essential to guarantee the safety of the battery pack. In the present study, an optimization method is developed to design the shape of the divergence and convergence plenums in an air-cooled battery thermal management system (BTMS) with parallel channels. The control points are used to describe the plenum shape, and the numerical simulation method is introduced to evaluate the performance of the BTMS. The height distribution of the control points is adjusted one step by one step, with the target of minimizing the temperature difference of the battery pack. Finally, the designed plenum shape is obtained according to the optimized height distribution of the control points. The results of typical cases show that the heat dissipation performance of the air-cooled BTMS with Z-type flow can be significantly improved after the plenum shape optimization using the proposed optimization method. Compared with those in the original system, the maximum temperature of the battery pack in the optimized system is more than 3.7 K lower, and the temperature difference is reduced by more than 85%, while the pressure drop of the system is only increased by 20% under different inlet flow rates. Compared with those in the optimized system in the literature, the temperature difference of the battery pack in the present optimized system is reduced by more than 48% without increasing the pressure drop.

Key words: heat transfer, numerical simulation, optimal design, air-cooled system, plenum shape

摘要：

针对并行流道风冷式动力电池热管理系统，开发了一种导流板形状优化方法。采用控制点描述导流板的形状，结合数值模拟方法，以电池组温差极小化为优化目标，通过逐步调整控制点高度优化导流板形状。典型算例结果表明，采用提出的优化方法优化Z形风冷系统的进口导流板形状，可显著提高系统的散热性能。在不同冷却空气流量下，与原始系统相比，优化后系统在压降增加20%的情况下，电池组最高温度下降了3.7 K以上，最大温差减小了85%以上；与文献中的Z形流道优化系统相比，本研究的优化系统在保证系统压降基本不变的情况下，电池组温差减小了48%以上。

关键词: 传热, 数值模拟, 优化设计, 风冷系统, 导流板形状