• CN:11-2187/TH
  • ISSN:0577-6686

机械工程学报 ›› 2017, Vol. 53 ›› Issue (10): 193-200.doi: 10.3901/JME.2017.10.193

• 交叉与前沿 • 上一篇    下一篇

大子午扩张变几何动力涡轮流场及损失特性分析

高杰1, 郑群1, 赵旭东2, 岳国强1, 王付凯1   

  1. 1. 哈尔滨工程大学动力与能源工程学院 哈尔滨 150001;
    2. 中国船舶重工集团公司第七零三研究所 哈尔滨 150078
  • 出版日期:2017-05-15 发布日期:2017-05-15
  • 作者简介:

    高杰(通信作者),男,1985年出生,博士,副教授,硕士研究生导师。主要研究方向为叶轮机械气动热力学。

    E-mail:gaojie_d@hrbeu.edu.cn

  • 基金资助:
    * 国家自然科学基金(51406039)和黑龙江省自然科学基金(QC2016059)资助项目; 20160605收到初稿,20161207收到修改稿;

Analysis of Flow Field and Loss Characteristics of High Endwall Angle Variable-geometry Power Turbine

GAO Jie1, ZHENG Qun1, ZHAO Xudong2, YUE Guoqiang1, WANG Fukai1   

  1. 1. College of Power and Energy Engineering, Harbin Engineering University, Harbin 150001;
    2. The 703 Research Institute of CSIC, Harbin 150078
  • Online:2017-05-15 Published:2017-05-15

摘要:

针对四级大子午扩张变几何动力涡轮开展数值计算研究,描述可调静叶端部间隙泄漏涡的形成过程,研究可调静叶转动前后可调静叶级三维流场结构及其损失机理的变化情况,分析静叶可调对动力涡轮各级总体性能的影响。研究结果表明:涡轮变几何引入了可调静叶端部部分间隙以及泄漏涡和通道涡的相互干扰,且泄漏涡涡核主要是由旋转轴后侧的泄漏流线组成;可调静叶转动不仅导致静叶自身出现攻角流动,还导致下游动叶前缘附近产生了大攻角分离流动,并且可调静叶关闭导致的动叶吸力侧大分离流动是由轮毂端壁附近分离泡螺旋向上运动产生,表现出强烈的三维特性,严重恶化变几何涡轮性能;可调静叶转动改变了静叶的喉部面积,导致涡轮级间焓降重新分配,从而在不同程度上影响动力涡轮各级流动性能,整体上对可调静叶级的影响最为明显。

关键词: 变几何, 流动分离, 损失特性, 泄漏流, 子午扩张, 动力涡轮

Abstract:

Numerical investigation is applied to a high endwall angle variable-geometry power turbine. The forming process of the variable vane endwall clearance leakage vortex is described. Then, the changes in the three-dimensional flow field and loss mechanisms of the variable turbine stage caused by the rotation of the variable vane are investigated. In addition, the effects of vane rotation on the overall performance of each power turbine stage are analyzed. The results show that, associated with turbine variable geometry, there are part clearances in the vane-end regions, which results in the existence of interaction zones of passage vortex and part clearance vortices. In addition, the core of the leakage vortex is made up of fluid that passes through the gap in the rear part of the rotating shaft. The rotation of the variable vane not only leads to the flow incidence to the vane self, but also results in a significant separated flow caused by high incidence near the downstream rotor leading edge. With the closing of the variable vane, the spiral upward movement of the separation bubble near the hub endwall induces the significant suction-side separated flow, showing strong three-dimensional flow characteristics, and it significantly deteriorates the variable geometry turbine performance. Besides, the rotation of the variable vane changes the vane throat area, redistributes the inter-stage enthalpy drop, and then affects each turbine stage performance to some extent. Overall, its effect on the variable geometry turbine stage is most obvious.

Key words: flow separation, high endwall angle, leakage flow, loss characteristics, variable geometry, power turbine