An efficient approximation for the vibro-acoustic response of a turbulent boundary layer excited panel

Abstract

21 pagesInternational audienceThe aim of this study was to present a deterministic model for approximating the vibrations and the acoustic pressure radiated when a thin elastic plate is immersed in a low Mach number flow of fluid. As a prelude to this study, a classical random model based on a wavevector integration technique was used. In the case of a low Mach number turbulent flow, the numerical study showed that the subconvective region of the turbulent excitation power spectrum contributes significantly to the response of the panel. A deterministic approximate model was developed, based on this behaviour of the system

Simulation of the pressure field beneath a turbulent boundary layer using realizations of uncorrelated wall plane waves

“…The wavenumber filtering effects of both the elastomer layer and the rectangular hydrophone were 75 highlighted by their approach. Mazzoni [17] proposed a deterministic model to approximate the response of an elastic rectangular plate at a low Mach number. The approximation was based on the observations of numerical studies showing that the subconvective region of the turbulent excitation power spectrum contributes significantly to the response of the panel.…”

“…It is an important advantage of the sampling method compared to the sensitivity approach. Moreover, more than 90% of the computation time of the sampling method corresponds to the synthetize of the WPF with (17). The 795 summation which appears in this equation is performed with a FOR loop in the MATLAB program, which is time consuming.…”

“…This explains why the results converge with a coarse mesh when the criterion (33) -first, it reduces the number of wall plane waves to be considered (i.e.    card ) in the process of synthetizing the WPF (17). As the computing time of this process is directly proportional to the number of wall plane waves considered, the time saving can be easily 750 deduced when using (33) instead of (34).…”

“…It is carried out by using the formula (17) and considering the wave amplitudes defined by Eq. (14).…”

Prediction of the response of a thin structure subjected to a turbulent boundary-layer-induced random pressure field

“…Innovative and fast solutions for the stochastic response of a plate have been carried out by many researchers [15][16][17][18][19]. Birgersson et al [15] used spectral finite element and dynamic stiffness methods to analyze the autospectral density of the velocity of a plate due to a turbulent boundary layer.…”