大尺寸高保真起落架构型气动噪声预测及降噪控制OA

Numerical simulation of landing gear noise and noise reduction design technologies are of great value and significance for the research and development of civil airliners.This study focuses on large-scale,high-fidelity landing gear configurations with complex geometries,conducting research on broadband aerodynamic noise numerical simula-tion.The prediction accuracy of far-field aerodynamic noise using various turbulence modeling methods,including the improved Delayed Detached Eddy Simulation(IDDES),the Wall-Adapting Local Eddy-Viscosity(WALE)model,and the Dynamic Smagorinsky Model(DSM),is systematically analyzed and evaluated.The results confirm that DSM of-fers the optimal frequency domain resolution for predicting noise in separated flows.Furthermore,the differences in far-field noise calculation using the Ffowcs Williams-Hawkings(FW-H)integration on the solid surface of the landing gear and on the refined mesh surface are compared.The findings indicate that the wall surface integration method exhibits significantly larger prediction deviations above 1 000 Hz in the high-frequency range compared to the refined surface method.Based on flow mechanism analysis,a noise reduction design method through flow rectification is proposed.By reshaping the geometry to suppress near-wall turbulence fluctuation intensity,the overall sound pressure level of landing gear noise is reduced by more than 5 dB across the 100～20 000 Hz frequency band.The research results provide theo-retical support for the refined prediction and flow control of aircraft landing gear aerodynamic noise.