摘要
以带有高低齿叶顶汽封的汽轮机高压第一压力级为研究对象,研究叶顶间隙和汽封齿数对叶顶泄漏量、叶顶间隙内和动叶出口的三维流线以及动叶出口熵增分布的影响,采用数值模拟方法进行三维定常流动计算.结果表明:随着叶顶间隙增加,叶顶泄漏量增加、动叶出口流线偏移加重、熵增的影响区域变大和掺混损失增加.随着叶顶汽封齿数增加,叶顶泄漏量减少、动叶出口流线偏移减轻、熵增变小以及掺混损失降低.叶顶泄漏流引起的掺混损失主要集中于动叶出口顶部7%的区域.
The three-dimensional steady numerical simulation was performed to study the influence of the tip clearances and the teeth number on the blade tip leakage flow rate,the three-dimensional streamlines in the seal and at the exit of rotor blade,and the distribution of entropy production at the exit of rotor blade,by taking the first high-pressure stage of a steam turbine with the blade tip stepped seal as object.Results indicate that the increase of tip clearance cause the increase of the leakage flow rate,the skewing of threedimensional streamlines at the exit of rotor blade,the region of entropy production and the mixing loss.The increase of teeth number of tip stepped seal cause the decrease of the leakage flow rate,the skewing of three-dimensional streamlines at the exit of rotor blade,the entropy production and the mixing loss.The mixing loss caused by blade tip leakage flow is mainly on the 7%region of the top exit of rotor blade.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2016年第8期1545-1550,共6页
Journal of Zhejiang University：Engineering Science
基金
国家自然科学基金资助项目(51576036)
关键词
汽轮机
叶顶汽封
泄漏流
熵增
三维流线
steam turbine
blade tip seal
leakage flow
entropy production
three-dimensional streamlines
