Thermal-structure Coupled Analysis Of HPT Tip Clearance And Its Effect On EGTM

Turbine tip clearance has great influence on engine performance.Bore scope inspecting image shows that the friction between the leading edge of the HPT blade and Shroud is severe,and the engine performance keeps low.The traditional tip clearance maintenance control of HPT has been unable to meet the requirements of engine safety and working performance any longer.Aiming at the grinding and maintenance of HPT blade in engine overhaul process,the influencing factors of HPT tip clearance are confirmed,the actual maintenance data and test data are both recorded and selected.In order to supply guidance for the grinding and maintenance of HPT blades under static conditions,it is necessary to obtain accurate tip clearance value of aero engine in the worst working conditions.Solid Works is adopted to establish the model of HPT disk and blade,ANSYS Workbench is used to conduct thermal-structure coupling analysis on turbine disk and blade to get their temperature field distribution and structural deformation under working status.It gets HPT blade leading edge and trailing edge of the actual tip clearance value under hot conditions.According to FEM analyzing result,the HPT leading edge grinding angle is adjusted in a certain type of aero engine under static condition to produce uneven clearance between the leading edge and trailing edge of blade tip position and the engine test is carried out.Based on the NUMECA,3D turbulence numerical simulation is used to simulate the flow field of HPT and calculate its efficiency as well as thermal efficiency of the whole engine under working state.The key performance parameters are analyzed and the influence of static uneven tip clearance on turbine efficiency and engine performance is studied in combination with maintenance and test data.Result shows that the uneven tip clearance maintenance scheme can reduce the friction of the Shroud and effectively improve the performance of HPT components and the engine.The grinding angle of HPT blade is adjusted by the study.The current research proves that the adjustment of HPT blade grinding angle can effectively improve the aero-engine EGTM after overhaul,reduce the maintenance and test work of HPT unit and significantly decrease the engine maintenance cost.