轴流排汽缸气动性能数值研究与改型优化  

Numerical simulation and optimization of aerodynamic performance for axial exhaust hood

作　　者：初鹏[1,2] 刘龙海[1,2] 辛小鹏[1,2] 马鑫磊[1,2] 隋永枫[1,2,3] 

机构地区：[1]杭州汽轮机股份有限公司工业透平研究院,浙江杭州310022 [2]浙江省工业汽轮机转子动力学研究重点实验室,浙江杭州310022 [3]浙江工业大学机械工程学院,浙江杭州310014

出　　处：《机电工程》2014年第8期1031-1034,共4页Journal of Mechanical & Electrical Engineering

摘　　要：为减小轴流排汽缸内部损失,提高排汽缸的气动性能,以杭州汽轮机股份有限公司新开发的轴流排汽缸为研究对象,考虑末级动叶出口径向速度不均匀性对排汽缸的影响,联合末两级整圈低压级组和排缸进行了数值计算。分析了轴流排汽缸内部流动特点,并根据流场对其进行了改型优化。计算结果表明,轴流排汽缸与低压级叶片之间存在相互作用,排汽缸后部出现两个旋流方向相反的涡,并随着气流向下游扩展;通过对轴流排汽缸结构改型,静压恢复系数提高了40.7%,总压损失系数减少了31.4%。通过优化通油管道的截面形状,使静压恢复系数提高了0.13%,总压损失系数减少了2.2%,改善了排汽缸内部流动,显著提高了轴流排汽缸的气动性能。Aiming at reducing the leaving velocity loss of the axial exhaust hood, improving the aerodynamic performance of the exhaust hood, numerical simulation was used to analysis the flow field of the axial exhaust hood which was designed by Hangzhou Steam Turbine Corporation considering about the influence of non-uniformity radial velocity field at the last blade exit. The axial exhaust hood was also modified for optimization. The results indicate that there are flow interactions between the exhaust system and low pressure turbine stages. There are two vortexes at the back of the exhaust hood. By changing the structure of the exhaust hood, static pressure recovery coefficient increases 40.68%, total pressure loss coefficient reduces 31.43%, by changing the cross section of the oil pipe, static pressure recovery coefficient increases 0.13%,total pressure loss coefficient reduces 2.2% ,also flow condition in exhaust hood outlet is improved.

关 键 词：汽轮机 轴流排汽缸 联合计算 改型优化 

分 类 号：TH122[机械工程—机械设计及理论] TK26[动力工程及工程热物理—动力机械及工程]