Unsteady experimental and numerical investigation of aerodynamic performance in ultra-high-lift LPT  

作　　者：Xiao QU Yanfeng ZHANG Xingen LU Junqiang ZHU 

机构地区：[1]Key Laboratory of Light-Duty Gas-Turbine,Institute of Engineering Thermophysics,Chinese Academy of Sciences,Beijing 100190,China [2]University of Chinese Academy of Sciences,Beijing 100190,China

出　　处：《Chinese Journal of Aeronautics》2020年第5期1421-1432,共12页中国航空学报（英文版）

基　　金：Financial support for this work from the National Natural Science Foundation of China (Nos. 51876202,51836008)

摘　　要：Detailed experimental and numerical investigations were performed for an ultra-high-lift front-loaded low-pressure turbine cascade (Zw=1.58) with periodic wakes.The interaction mechanisms between the incoming wakes and endwall secondary flow were carefully examined.Wakes were produced by moving upstream rods,and flow field downstream of the cascade was measured using a seven-hole probe.Experimental results revealed that incoming wakes influenced not only the boundary layer development of the blade suction surface but also the complex endwall secondary vortex structures.On the suction surface:Incoming wakes clearly suppressed the suction side separation bubble at a low Reynolds number of 25000.Nevertheless,the effects of different wake passing frequencies were not significantly different at Re=100000,and the profile losses under wake passing were even greater than in the absence of wakes.At the end walls:Incoming wakes more strongly suppressed secondary flow at Re=100000 than at Re=25000,because the lowmomentum fluid inside the incoming wakes clearly increased the endwall cross-passage pressure gradient at Re=25000.The experimental results indicated that periodic wakes decreased the passage vortex and counter vortex core strength by 25% and 30%,respectively,at Re=100000.Instantaneous results also demonstrated that endwall secondary vortices decreased significantly near the position of wakes passing.

关 键 词：Experimental investigation Low pressure turbine Periodic wake Secondary flow Ultra-High-lift 

分 类 号：TK401[动力工程及工程热物理—动力机械及工程]