The Implications of Tolerance Optimization on Compressor Blade Design

Abstract

Geometric variability increases performance variability and degrades the mean performance of turbomachinery compressor blades. These detrimental effects can be reduced by using robust optimization to design the blade geometry or by imposing stricter manufacturing tolerances. This paper presents a novel computational framework for optimizing compressor blade manufacturing tolerances and incorporates this framework into existing robust geometry design frameworks. Optimizations of an exit guide vane geometry are conducted. When the design is optimized to improve performance at a single operating point, the optimal geometry is found to depend on the manufacturing tolerances due to a switch in the dominant loss mechanism. Including multiple operating points in the optimization avoids this switch so that the geometry and tolerance optimization problems are decoupled.