Control of squealer-tip leakage flow with perforated-rib coolant injection in an axial turbine cascade  

作　　者：Shengchang ZHANG Qinqin WANG Xiaoming TAN Jingzhou ZHANG 

机构地区：[1]College of Energy and Power Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China [2]School of Energy and Power Engineering,Beihang University,Beijing 100191,China [3]AECC Sichuan Gas Turbine Research Establishment,Chengdu 610500,China

出　　处：《Chinese Journal of Aeronautics》2023年第8期54-73,共20页中国航空学报（英文版）

基　　金：supported by the National Science and Technology Major Project,China(No.2017-III-0001-0025);the Interdisciplinary Innovation Foundation for Graduates at Nanjing University of Aeronautics and Astronautics in China(No.KXKCXJJ202002).

摘　　要：A novel perforated-rib configuration is proposed for controlling the tip leakage flow at the rotor tip of an axial turbine.Three perforated-rib layouts are considered,wherein a perforated rib is installed at(A)the Suction-Side squealer(SS-rib),(B)the Pressure-Side squealer(PS-rib),and(C)the additional squealer along the blade Camber Line(CL-rib).A numerical method is used to show how the novel rib layouts affect the aerodynamic performance of the tip leakage flow.Results show that the coolant jets issuing from the perforated-rib injection holes penetrate deeper into the tip clearance than those in the baseline squealer-tip case,and how the perforated-rib coolant injection affects the tip leakage flow depends strongly on the rib layout.The PS-rib and CL-rib layouts appear promising for controlling the tip leakage flow,playing a significant role in reducing the total pressure loss and improving the turbine blade’s isentropic efficiency.In particular,under an injection mass flow ratio of 1%and a tip clearance of 1%blade span,the PS-rib layout reduces the leakage mass flow rate by 27%and increases the isentropic efficiency by 1.25%compared with those in the baseline squealer-tip case.Meanwhile,the advantages of the PS-rib layout in tip leakage control are confirmed under small and large tip clearances.

关 键 词：AERODYNAMICS Perforatedrib Squealer tip Tip injection Tipleakageflow 

分 类 号：V263.6[航空宇航科学与技术—航空宇航制造工程]