板翅式机油冷却器的性能仿真与优化

为研究板翅式机油冷却器各层芯片内机油的流动及换热情况,优化板翅式机油冷却器的芯板层数,基于有限元分析软件ANSYS的参数化设计语言,编程建立了不同芯片层数的多个油冷器的有限元模型;翅片简化为多孔介质,借助计算流体力学软件Fluent,得到油冷器各层芯片的流场和温度场分布.仿真结果与实验结果吻合良好.油冷器各层芯片流量分配曲线大致呈S形分布,而换热量分配曲线呈浴盆状分布.引入标准偏差判断各油冷器各层流量和换热量的均匀性,随着油冷器芯片层数的增多,各层芯片流量和换热量分配趋于均匀;总体换热性能略有增大,而单层芯片的平均换热量显著减小.根据仿真结果提出优化建议:在设计油冷器时,应避免单层芯片热负荷过高或过低,在机体内部空间允许的条件下应尽量采用较多层芯片.

The Performance Simulation and Optimization on Plate Fin Oil Coolers

In order to study the flow and heat transfer quantity distributions and optimize the numbers of core layers for plate fin oil coolers,models of oil coolers with various core layers were constructed parametrically,based on the finite element analysis software ANSYS parametric design language.Fin was simplified as porous medium,and with the help of computational fluid dynamics program "Fluent",the flow and temperature distributions were obtained.The calculated and experimental results agree well.The oil flow rate distribution curve mainly has an "S" shape,and the heat transfer rate shows a "bathtub" distribution. Standard deviation was adopted to judge the uniformities of oil flow rate and heat transfer rate.The regulation of oil coolers performance vs numbers of core layers was derived.With the increase of layers,the distributions of oil flow rate and heat exchange rate tend to be even;the global heat transfer performance increases slightly,but the mean heat exchange rate for single core assemblies decreases distinctly.According to the optimization results,it is advised that oil coolers with more core layers be adopted considering enough mount space during the design process.