汽轮机高压级叶顶间隙流的特性分析  

Analysis on Flow Characteristic in Blade Tip Clearance in High-pressure Stage of Steam Turbine

作　　者：曹丽华[1] 胡鹏飞[1] 李涛涛[1] 李勇[1] 周云龙[1] 

机构地区：[1]东北电力大学能源与动力工程学院,吉林省吉林市132012

出　　处：《中国电机工程学报》2011年第23期86-93,共8页Proceedings of the CSEE

基　　金：吉林市科技发展计划资助项目(201030003);东北电力大学研究生创新基金资助~~

摘　　要：以某300 MW汽轮机高压级为研究对象,采用带剪切应力传输(shear stress transmission,sst)的κ-ωsst湍流模型,应用SIMPLEC算法对不同叶顶间隙下的泄漏流动进行数值模拟,分析了泄漏涡的产生、发展及与通道涡的干涉情况,并研究了3种叶顶间隙下,动叶叶顶处复杂的流动和涡系情况。结果表明,压力面附近的流体由于压力面和吸力面的压力差作用进入叶顶间隙,泄漏到吸力面处,与主流掺混形成泄漏涡。随着叶顶间隙的增加,泄漏涡强度变大,导致通道涡靠近叶片中部。同时,泄漏涡涡核离吸力面更远,使通道内的流动环境更恶劣,引起更大的级内损失。This paper reports a numerical study on leakage flow with different blade tip clearances in high-pressure stage of a 300 MW steam turbine. The k-w sst turbulence model was adopted, and SIMPLEC arithmetic was used. The formation, development of leakage vortex and the interference between leakage vortex and passage vortex were analyzed. Also, the complex flow and vortex system in moving blade tip were studied, comparing the performance with different three kinds of blade tip clearances. The results show that due to the pressure gradient which is formed between the pressure side and the suction side, the fluid near the pressure side is absorbed into the blade tip clearance. The fluid leaks to the suction side, and forms the leakage vortex mixing with the mainstream finalIy. The leakage vortex is strengthened with the increase of the tip clearance height, causing the passage vortex to approach the middle of blade seriously. At the same time, the core of the leakage vortex is more farther from the suction side. It leads to bad surroundings in the flow passage, and causing consequently fluid losses to increase.

关 键 词：汽轮机 叶顶间隙 叶顶泄漏涡 数值模拟 

分 类 号：TK263[动力工程及工程热物理—动力机械及工程]