Enhancement of Efficiency by Blade Optimization in a Single-Stage Transonic Axial Compressor

초록

Shape optimization of rotor and stator blades has been studied in a single-stage transonic axial compressor. Two shape variables, which are used to define a stacking line for the both blades, are introduced to increase an adiabatic efficiency of the compressor. The adiabatic efficiency is selected as an object function, and the blade optimization is performed using a response surface method. Three-dimensional Navier-Stokes equations are introduced to analyze the internal flow of the compressor. An algebraic turbulence model of Baldwin and Lomax is employed to estimate the eddy viscosity. Throughout the shape optimization of rotor and stator blades, the adiabatic efficiency is increased by decreasing local losses near the blade surfaces. The increase of the efficiency is mainly caused by moving the separation line to the downstream on the blade suction surface. It is noted the increase of adiabatic efficiency by optimization of the blade shape with the stacking line in the single-stage transonic axial compressor is more effective in a rotor blade rather than a stator blade because of the large deformation of blade shape in the stator blade.