Prediction system for rotor–stator interaction noise generation, propagation, and optimization of acoustic liners

Abstract

Based upon the acoustic mode matches between the source modes and propagating modes, this paper applies the flexible tolerance optimization method to optimize the acoustic parameters (impedance), geometric structure parameters, such as open area ratio, cavity depth, and hole diameter, and operating condition parameters, such as blade passing frequency. The optimum values of the design variables are determined when the in-duct sound suppression approaches the maximum. It can be derived from the optimum results that the emphasis of the engineering optimization design of the perforated plate honeycomb structure should be placed on the optimum choice of the open area ratio and cavity depth. Some other referential criteria for the engineering design of the multi-linings are also provided. Thus, the theoretical prediction system for rotor–stator interaction noise generation and in-duct propagation and optimization of acoustic liners has been developed in this paper. By means of this prediction system, the acoustically multi-sectioned treatments can be theoretically designed for the suppression of rotor–stator interaction noise with discrete frequency, in advance of the beginning of the practical engineering design of acoustic liners.