基于CFD的液冷板数值模拟与优化研究

Numerical simulation and optimization of liquid cooling plate based on CFD

通过对动力锂电池温度的控制,可以大大提高电动汽车用锂电池的性能,有效的热管理系统对于控制电池温度至关重要。液冷板常用在锂电池液冷系统中,具有高效的冷却能力。液冷板通常为薄的金属件,包括一个或多个内部通道,冷却液通过泵送的形式在液冷系统中流动,热量从电池组传导到液冷板,再由冷却液输送出去。液冷板散热特性取决于其内部通道的几何形状、流道路径、流道长度、宽度等参数。文中建立了液冷板流道的参数化模型,基于计算流体动力学(CFD)对液冷板的内部流场进行了数值模拟。确定了出口支路流量一致和进出口压差最小的目标函数,通过建立出入口总宽度和支路宽度的约束来进行数值优化。采用最优拉丁超立方设计方法对设计变量均匀分布样本点,并通过Isight求解出满足优化目标的液冷板结构。优化结果表明,所采用的优化方法成功用于液冷板的多目标优化,设计者可根据优化结果权衡各目标,以指导热管理系统的开发。

By controlling the temperature of lithium batteries,the performance of lithium batteries used in electric vehicles greatly improves;an effective system of thermal management is essential for temperature controlling.Liquid cooling plates are commonly used in lithium batteries’liquid cooling systems and have efficient cooling capability.Liquid cooling plates are usually thin metal parts,including one or more internal channels.The coolant flows through the liquid cooling system in the form of pump;heat is conducted from the battery pack to the liquid cooling plate,and then transported out by the coolant.The heat-dissipation characteristics of the liquid cooling plate depend on the internal channel geometry,channel path,channel length,width and other parameters.In this paper,a parametric model of the liquid cooled plate’s flow channel is set up,and the internal flow field is numerically simulated based on the computational fluid dynamics(CFD).The objective functions of the uniform flow rate and the minimum pressure difference between the inlet and outlet are determined,and numerical optimization is performed by establishing constraints on the total width of the inlet and outlet as well as the width of the branches.The optimal Latin hypercube method is adopted to evenly distribute the sample points of design variables,and the liquid cooling plate’s structure that meets the optimization requirements is solved by means of Isight.It’s shown that this method is successfully applied to the multi-objective optimization of liquid cooling plates.Designers can handle the trade-off between the objectives according to the optimization results,in order to provide guidance for development of thermal-management systems.