工程车辆散热器的传热特性分析与结构优化

为提高某工程车辆用管片式散热器性能,提出在散热器热管外壁增加导流结构作为改进方案。首先,采用Fluent15.0对原始散热器单元体进行仿真,对比试验数据验证仿真的准确性;其次,在原始散热器单元体的热管外壁增加导流结构作为改进模型,对比改进前后散热器的综合性能;最后,分析导流结构各参数的传热特性并优化导流结构。仿真结果表明:在入口风速为2～12 m/s时,仿真结果与试验数据的压力损失和换热系数的最大偏差在5%以内;入口风速为12 m/s时,改进模型的综合评价因子高出原始模型约6.73%;导流结构的长度、半径与散热器的压力损失和换热系数成正比,而安装位置则与之成反比,结合正交试验与信噪比分析得出的最优导流结构参数为半径r=0.5 mm,长度h=3.0 mm,位置p=5.8 mm。该研究为导流结构在散热器中的应用提供了新的经验认知。

Analysis and optimization of heat transfer characteristics about radiator diversion structure

In order to improve the performance of the fin-and-tube radiator for a project vehicle, adding a diversion structure to the outer of the radiator tube is a new improvement scheme. First, fluent15.0 was used to simulate the original radiator unit, and the experimental data were compared to verify the accuracy of the simulation. Secondly, the tube of the original radiator unit was added with a diversion structure as the improved model to compare the comprehensive performance of the radiator before and after the improvement. Finally, the heat transfer characteristics of the structure parameters were analyzed and the structure was optimized. The simulation results show that the maximum deviation of pressure loss and heat transfer coefficient between simulation results and test data is within 5% in the range of 2-12 m/s of velocity. When the velocity is 12 m/s, the comprehensive evaluation factor of the improved model is about 6.73% higher than that of the original model. The length and radius of the diversion structure are directly proportional to the pressure loss and heat transfer coefficient of the radiator, while the installation location is inversely proportional to it. The optimal diversion structure parameters obtained by combining orthogonal test and SNR analysis are radius r= 0.5 hmm, length h= 3.0 mm, and position p= 5.8 mm. This study provides a new empirical understanding for the application of diversion structures in radiators.