Rotating Stall Suppression in Axial Compressors with Casing Plasma Actuation

摘要

This paper proposes the use of single dielectric barrier discharge, or plasma, actuators to suppress rotating stallninception and extend the stable operating range of axial compressors. Plasma actuatorsmay provide a practical low-npower alternative to effectively increase the surgemargin of aircraft engineswithminimal or even positive impact onncompressor performance. A computational study is carried out on a representative subsonic modern compressornrotor geometry to evaluate the proposed casing plasma actuation for suppression of short (spike) as well as longn(modal) length-scale rotating stall inception based on their respective flow physics. The objective is to assess thenoptimumactuator location and required actuation strength to achieve the desired effects at lowandmediumsubsonicncompressor speeds. Results show that plasma actuation near the rotor leading edge and concentrated in the tipnclearance gap regionmost effectively suppresses both of the criteria for spike stall inception and delays the predictednstall point to a lower flow coefficient with relatively low power input. In addition, the observed increase in rotornpressure-rise characteristic from the proposed actuation means that the concept, with a new suggested actuatornmodification, can also be used to suppressmodal stall inception. The simulations indicate that actuation effectivenessndecreaseswith increasing rotor tip speed, that the required actuator strength scaleswith this speed, and that strongernactuation strength than that of conventional single dielectric barrier discharge plasma actuators may be needed.nSome implications for the practical implementation of this concept on real compressors are also discussed.