机匣相对转动对涡轮叶顶间隙流动的影响  

Effects of endwall relative motion on tip clearance flow in turbine rotors

作　　者：牛茂升[1] 臧述升[1] 

机构地区：[1]上海交通大学机械与动力工程学院叶轮机械研究所,上海200240

出　　处：《空气动力学学报》2009年第5期597-601,共5页Acta Aerodynamica Sinica

基　　金：国家重点基础研究发展计划(2007CB210102)

摘　　要：机匣与叶片的相对转动是影响涡轮叶顶间隙流动的重要因素之一。对LISA 1.5级轴流涡轮内三维流动的数值计算结果表明:当叶片静止时,叶片顶部压力面静压增加,叶片顶部载荷增大。通过间隙的流量增加,同时吸力面侧在叶片前缘、叶片中部各形成一个间隙涡。叶片前缘间隙涡会迅速耗散,同时使得叶片中部形成的间隙涡维持在吸力边附近,上通道涡被排挤到间隙涡下方,导致动叶出口截面上、下通道涡形成的高损失区合并,影响范围增大。Endwall relative motion is one of the most important factors that affect tip clearance flow in turbine rotors, thus this paper presents a numerical investigation of its influence on the complicated flow structures inside LISA 1.5-stage axial turbine. The results indicate that when blades are stationary, the static pressure increases on the pressure surface around blade tip regions, leading to much more tip clearance mass flow. Another more tip clearance vortex appears near the leading edge, which dissipates quickly and keeps the regular one almost near the suction surface. Tip passage vortex is forced to move towards the midspan, resulting in the combination of two high loss regions caused by to tip and hub passage vortex.

关 键 词：间隙流动 间隙涡 叶顶分离涡 通道涡 

分 类 号：TK474.7[动力工程及工程热物理—动力机械及工程]