Internal fuselage noise: comparison of computations and tests on a Falcon airframe

An unequipped Falcon 2000 airframe, a complex heterogeneous structure reduc ed to the fuselage alone, was subjected to vibro-acoustic characterization within the framework of a cooperative effort by Aerospatiale, Dassault-Avia tion, and Onera. Onera's Structural Dynamics and Coupled Systems Department measured the structure's vibro-acoustic responses for four mechanical exci tation configurations, and analysed three structural configurations: fusela ge alone without floor, with floor, and with floor and internal wall. The r esulting database of vibratory and acoustic level measurements is used for validating numerical models in the low- and medium-frequency range, as well as statistical energy analysis (SEA) models in the medium- and high-freque ncy range. The database was analysed by Dassault-Aviation and Onera. We present here t he computation/test comparisons and the limitations of the methods in use. All of the data and comparisons validate the predictive vibro-acoustic resp onse models and methods for a Falcon fuselage subjected to a mechanical exc itation. (C) 2000 Editions scientifiques et medicales Elsevier SAS.