排汽缸全局气动优化及设计知识挖掘方法  

Global Optimization of Aerodynamic Design and Knowledge Discovery Method of an Exhaust Hood

作　　者：祝培源 郭振东[1] 陈红梅[1] 宋立明[1] 李军[1] 

机构地区：[1]西安交通大学叶轮机械研究所,西安710049

出　　处：《西安交通大学学报》2015年第11期26-32,共7页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(51106123)

摘　　要：为了提高排汽缸的气动性能,探索排汽缸的设计规律,耦合基于子元模型的全局优化算法、三阶贝塞尔曲线的三维排汽缸参数化方法、RANS(Reynolds-Averaged Navier-Stokes)方程求解方法与基于总变差分析的数据挖掘技术,提出了健壮高效的排汽缸设计优化与知识挖掘方法。在考虑末级叶片和排汽缸之间相互作用的基础上,选取静压恢复系数最大为目标函数,对低压排汽缸进行了设计优化与知识挖掘。优化得到的排汽缸静压恢复系数从0.165提高到了0.516。采用基于总变差分析的数据挖掘技术并结合排汽缸气动性能分析,阐明了设计变量与目标函数之间的相互影响机制。研究结果表明:扩压器出口宽度、排汽缸外缸宽度、外导流环高度和外导流环出口角度对排汽缸气动性能有显著影响。所建立的排汽缸优化设计方法和知识挖掘技术为高性能排汽缸设计提供了工具。To improve the aerodynamic performance and explore design guidelines for an exhaust hood, a robust and efficient design optimization and data mining method, which combines meta- based global optimization algorithm with a 3rd-order Bezier curve-based 3D parameterized method, Reynolds-Averaged Navier-Stokes （RANS） solver technique and data mining technique based on variance analysis, is proposed for the aerodynamic optimal design of an exhaust hood. By fully taking into account the interaction between the last turbine stage blades and exhaust hood, design optimization and knowledge discovery of a low-pressure exhaust hood are carried out for maximizing the static pressure recovery coefficient. The static pressure recovery coefficient of the optimal exhaust hood is improved from 0. 165 to 0. 516. The interactions among design variables and objective function are illustrated using the data mining technique combined with detailed aerodynamic analysis. The research results indicate that the diffuser outlet width, the outer hood width, the outer flow guider＇s height and the outer flow guider＇s outlet angle have significant effects on the performance of the exhaust hood. The proposed design optimization and data mining method for the exhaust hood provide a basis for the design of high-performance exhaust hood.

关 键 词：排汽缸 静压恢复系数 全局优化设计 知识挖掘 

分 类 号：TK474.7[动力工程及工程热物理—动力机械及工程]