A NOVEL METHOD FOR IMPROVEMENT OF AERODYNAMIC PERFORMANCE OF HIGHLY LOADED LP TURBINE AIRFOILS FOR AEROENGINES

摘要

This paper proposes a novel method to improve aerodynamic performance of highly loaded Low-Pressure (LP) turbine airfoils for aeroengines over a relatively wide range of Reynolds number. This new method employs two types of approaches; one is the equipment of two-dimensional contouring with small step on the suction surface of the airfoil and the other approach is a re-shaping of the airfoil near the trailing edge. A linear cascade test facility is employed to investigate the aerodynamic performance of the newly proposed airfoils by use of a miniature Pitot probe. Suction surface boundary layers as well as airfoil wakes are also measured using a hot wire probe. In the experiment, various flow conditions, Reynolds number, wake-passing Strouhal number, are examined. Numerical simulations are carried out to have a better understanding of the flow field around the airfoil. URANS and LES are employed for this purpose. It is found that the proposed method has a capability to reduce the profile loss to some extent.