风冷柴油机高负荷轴流冷却风扇气动优化  

Aerodynamic Optimization of a High-Load Axial Cooling Fan for an Air-Cooled Diesel Engine

作　　者：任贵峰 王睿 刘正先[1] 李孝检 REN Guifeng;WANG Rui;LIU Zhengxian;LI Xiaojian(School of Mechanical Engineering,Tianjin University,Tianjin 300350,China;China North Engine Research Institute,Tianjin 300400,China)

机构地区：[1]天津大学机械工程学院,天津300350 [2]中国北方发动机研究所,天津300400

出　　处：《内燃机工程》2024年第5期11-18,27,共9页Chinese Internal Combustion Engine Engineering

基　　金：国家自然科学基金项目(12102298)。

摘　　要：针对某型风冷柴油机的具有负预旋前置导叶的冷却风扇,考虑导叶和转子的耦合效应,基于多项式代理模型和第二代非支配排序遗传算法实施了冷却风扇多目标气动优化。优化后的效率和全压在近失速工况分别提升1.19%、4.78%,在设计工况分别提高0.29%、3.16%。采用Sobol全局敏感性分析辨识了关键设计变量,结合优化前后流场变化,获得了风扇气动性能提升的流动机理:导叶叶根安装角的减小和转子叶根安装角的增大,共同减小了转子进口攻角,从而增大风扇等熵效率,并弥补了因欧拉功减小所致的全压降低;转子叶顶安装角减小,在削弱叶根与叶顶扩压不平衡度的同时补偿了全压的损失。For a cooling fan with negative prewhirl front stator of an air-cooled diesel engine,by considering the coupling effect of the stator and the rotor,the multi-objective aerodynamic optimization of the cooling fan was implemented based on the polynomial surrogate model and the non-dominated sorting genetic algorithmⅡ.The optimized efficiency and total pressure increased by 1.19%and 4.78%respectively under the near-stall condition,and increased by 0.29%and 3.16%respectively under the design condition.The key design variables were identified by Sobol’s global sensitivity analysis method,and the flow mechanisms for improving the aerodynamic performances of the fan were obtained by combining the changes of the flow fields before and after optimization.The decrease of the hub blade angle of the stator and the increase of the hub blade angle of the rotor jointly reduce the angle of attack of the rotor inlet,thereby increasing the isentropic efficiency of the fan,and making up for the total pressure reduction caused by the decrease of Euler work.The tip blade angle of the rotor is reduced,which weakens the imbalance between the hub and the tip regions,and compensates for the loss of total pressure.

关 键 词：风冷柴油机 冷却风扇 气动优化 全局敏感性分析 流动机理 

分 类 号：TK422[动力工程及工程热物理—动力机械及工程]