空气域与流体域耦合作用下双层电池包散热特性

多层垒叠电池包内空气域的存在使各层模组热流场耦合在一起，从而影响电池模组的散热性能。以方形双层电池包为研究对象，建立考虑电池模组与空气对流换热的液冷热模型。该模型中电池发热功率基于试验测定结果，前处理软件采用ANSA确保仿真精度，后处理软件采用CFX，对在不同放电倍率、冷却液进液方向和进液流量下双层电池结构中空气域对液冷热管理系统热行为的影响进行了研究，并与不考虑空气域同工况仿真结果对比。结果表明:空气域的存在不会对液冷双层电池包上下层模组温度分布产生影响；但可以降低上下层模组间的温差，其中上下层模组最高温升的差值最大可降低49.1%，改善了整包电池温度的一致性。 

Heat dissipation characteristics of double-layer battery pack under coupling of air and fluid domains

The existence of the air domain in the multi-layer stacked battery pack makes the heat flow field of each layer module coupled together, thus affecting the heat dissipation performance of the battery module. A liquid-cooled heat transfer model for a square double-layer battery pack is established with considering the convection heat transfer between the battery module and the air. The thermal power of the battery in this model is based on the experimental results. ANSA is used as the pre-processing software to ensure the simulation accuracy, and CFX is used as the post-processing software. The effect of air domain in double-layer battery structure on the thermal behavior of liquid-cooled thermal management system is studied under different discharge rates, cooling fluid inlet directions and liquid flow rates. It is compared with the simulation result without the consideration of air domain under the same working condition. The comparison results show that the presence of the air domain does not affect the temperature distribution of upper and lower module of the liquid-cooled double-layer battery pack, but reduces the temperature difference of the upper and lower modules, and the difference of the maximum temperature rise in the upper and lower modules can be reduced by 49.1% to a largest extent, which improves the temperature consistency of the whole battery pack.