A study on an integrated aero-vibro-acoustic analysis procedure for a small-scale supersonic jet and surrounding thin plates

Abstract

The goal of this paper is to examine the computational approaches for predicting both of the overall sound pressure level (OASPL) at a few locations and acceleration power spectral density (APSD) of surrounding thin plates due to the aero-acoustic pressure generated by a cold jet with M = 1.8. First, computational fluid dynamics (CFD), particularly delayed detached eddy simulation, are applied to predict the OASPL at the near-field and compute the acoustic properties. Second, the linearized boundary element method (BEM), that is, the Helmholtz-Kirchhoff method is utilized to propagate the pressure and obtain the OASPL at the far-field. Finally, the finite element method is implemented to predict the APSD for a clamped thin plate based on the optimal triangle membrane element, discrete Kirchhoff triangle plate bending element, and Newmark-β time integration scheme. Using the present CFD and BEM, the OASPLs are compared with the experimental results measured by microphones at both the near- and far-fields, respectively. Moreover, APSDs are compared with the experimental results obtained by an accelerometer at a few different locations. Although OASPLs are overestimated because of the coarse meshes in the higher-angle area and low order scheme of the present CFD analysis, the present integrated aero-vibro-acoustic analysis is capable of predicting the OASPL and APSD generated by a cold jet with M = 1.8.