基于集群效应的独立式冷却模块气动特性研究

为了研究独立式冷却模块中多热交换器气动特性之间的集群效应，以典型双热交换器工程机械独立式冷却模块为例进行试验与数值仿真研究. 采用多孔介质模型模拟热交换器，利用多重参考坐标系方法模拟风扇性能，建立4种不同热交换器布置方案下的独立式冷却模块数值模型，对比分析气动特性，并进行冷却模块气动性能试验；通过改变热交换器间面积比与厚度比，完成独立式冷却模块气动特性主动控制方法的数值仿真研究. 研究结果表明:独立式冷却模块气动特性上具有独特的集群效应，即当热交换器呈对置方式布置时，不论两者的倾斜角度如何，气动阻力都相等；数值仿真发现相比于面积比控制，当采用厚度比控制的主动控制策略时，改变独立式冷却模块热交换器之间的厚度比，流量比变化更为平缓，且受风扇转速的影响更小，并据此得到两热交换器之间冷却风量、气动阻力与结构参数之间的试验关联式. 

Study of Aerodynamic Characteristics in Detached Cooling Module Based on Cluster Analysis

Numerical and experimental studies were conducted to investigate the cluster effect of aerodynamic characteristics in detached cooling modules with multiple types of heat exchangers, considering the typical dual heat exchangers in construction machinery cooling modules as examples. The porous media model was used to simulate the heat exchanger, and the multiple reference frame method was used to simulate fan performance. Numerical analyses and further experimental research of the cooling modules were conducted under four different heat exchanger arrangements. Using numerical methods, the control method for the aerodynamic characteristics of an independent cooling module was studied by adjusting the area and thickness ratios of the heat exchanger. The experimental and numerical simulation results show that the aerodynamic characteristics of the independent cooling module is unique: when the two heat exchangers are arranged in opposing positions, the aerodynamic drag is equal regardless of the inclination angles of the exchangers. Numerical simulations of the active control method for aerodynamic characteristics show the following: Compared to modifying the area ratio of the heat exchanger, thickness ratio modification is a active control strategy because the flow rate ratio changes more gently and is less affected by the fan speed. Based on these findings, the experimental correlations among cooling air volume, aerodynamic drag, and structural parameters of the two heat exchangers are obtained.