多级低压涡轮内部非定常流场扰动分析  

Numerical Investigation on Unsteady Flow and Perturbation in a Multistage Low Pressure Turbine

作　　者：邵飞[1] 綦蕾[1] 周颖[2] 李恩华[2] 

机构地区：[1]北京航空航天大学能源与动力工程学院航空发动机气动热力国家级重点实验室,北京100191 [2]中国航空工业集团公司中国航空动力机械研究所,湖南株洲412002

出　　处：《燃气涡轮试验与研究》2013年第5期23-29,共7页Gas Turbine Experiment and Research

基　　金：国家自然科学基金(51106004)

摘　　要：采用三维数值模拟方法,对带有过渡段和后机匣支板的低压涡轮进行全环非定常数值模拟,分析了各个叶片排流场中存在的非定常扰动及扰动源,研究了低压涡轮第二级中存在的多种扰动源叠加现象,并对流场中的静压波动进行了频谱分析。结果显示,过渡段的二次流对低压涡轮内部流场存在明显扰动,并向下游传播至涡轮出口。第二级动叶中,上游导叶通过频率与过渡段二次流自身脉动频率产生叠加,形成的新扰动频率为两者产生的差频。采用全环非定常数值模拟预测多级低压涡轮内部流动中存在的各种扰动频率及其相互叠加很有必要。Three dimensional numerical simulations are conducted to investigate the unsteady flow field in a full scale low pressure turbine with intermediate turbine duct and rear casing. Several perturbations and their sources in each blade passage are analyzed, and the pressure fluctuation of flow field where monitoring points located is investigated with frequency analysis. Disturbance sources＇ frequency superposition is also introduced. Numerical results show that perturbation developed by secondary flow from intermediate tur- bine duct and propagated to the outlet is obvious in the flow filed. In the rotor field of the second stage, the upstream vane passing frequency and inherent frequency of secondary flow from intermediate turbine duct are stacking and a new disturbance frequency is formed. For accurately predicting the perturbations and fre- quency superposition phenomenon of unsteady flow in a multistage low pressure turbine, it is necessary to investigate the flow field with full scale simulation.

关 键 词：低压涡轮 全环非定常数值模拟 非定常扰动 频谱分析 差频 

分 类 号：V235.1[航空宇航科学与技术—航空宇航推进理论与工程]