The Impact of Manufacturing Variations on Performance of a Transonic Axial Compressor Rotor

Abstract

In this paper, the impact of manufacturing variations on performance of an axial compressor rotor is evaluated at design rotational speed. The geometric variations from the design intent obtained from measurements were used to evaluate the impact of manufacturing variations on performance and the flow field in the rotor. The complete blisk is simulated using 3D computational fluid dynamics calculations, allowing for a detailed analysis of the impact of geometric variations on the flow. It is shown that the mean shift of the geometry from the design intent is responsible for the majority of the change in performance in terms of mass flow and total pressure ratio for this specific blisk. In terms of polytropic efficiency, the measured geometric scatter is shown to have a higher influence than the geometric mean deviation. The geometric scatter around the mean is shown to impact the pressure along the leading edge and the shock position. Furthermore, a blisk is analyzed with one blade deviating substantially from the design intent. It is shown that the impact of this blade on the flow is largely limited to the blade passages that it is directly a part of. It is also shown that the impact of this blade on the flow field can be represented by a simulation including three blade passages. In terms of loss, using five blade passages is shown to give a close estimate for the relative change in loss for the blade deviating substantially from the design intent and for the neighboring blades.