One important topic in the aeronautic and aerospace industries is the reproduction of random pressure field, with prescribed spatial correlation characteristics, in laboratory conditions. In particular, the random-wall pressure fluctuations induced by a Turbulent Boundary Layer (TBL) excitation are a major concern for cabin noise problem, as this udexcitation has been identified as the dominant contribution in cruise conditions. As in-flight measurements require udcostly and time-consuming measurement campaigns, the laboratory reproduction has attracted considerable attention udin recent years. Some work has already been carried out for the laboratory simulation of the excitation pressure field udfor several random fields. It has been found that TBL reproduction is very demanding in terms of number of loudspeakers per correlation length, and it should require a dense and non-uniform arrangement of acoustic sources due to udthe different spanwise and streamwise correlation lengths involved. The present study addresses the problem of directly simulating the vibroacoustic response of an aircraft skin panel using a near-field array of suitably driven loudspeakers. It is compared with the use of an array of shakers and piezoelectric actuators. It is shown how the udwavenumber filtering capabilities of the panel reduces the number of sources required, thus dramatically enlarging udthe frequency range over which the TBL vibro-acoustic response is reproduced with accuracy. Direct reconstruction udof the TBL-induced panel response is found to be feasible over the hydrodynamic coincidence frequency range using uda limited number of actuators driven by optimal signals. It is shown that piezoelectric actuators, which have more udpractical implementation than shakers, provide a more effective reproduction of the TBL response than near-field udloudspeakers.
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