||CMES: Computer Modeling in Engineering & Sciences, Vol. 61, No. 1, pp. 1-22, 2010
||Full length paper in PDF format. Size = 505,018 bytes
||energy finite element method, structural-acoustic coupling, aircraft cabin.
||Energy finite element method (EFEM) is a new method to solve high-frequency structural-acoustic coupling problems, but its use has been limited to solving simple structures such as rods, beams, plates and combined structures. In this paper, the high-frequency structural-acoustic coupling characteristics of an aircraft cabin are simulated by regarding the shell as a number of flat shell elements connected with a certain angle in EFEM. Two tests validated the method employed in this paper. First, the structural response analysis of a cylinder was calculated in two ways: dividing the shell by axis-symmetric shells after deriving the governing equation of axis-symmetric vibration; and using flat shell elements to approximate the shell structure, as proposed by this paper. The second verification used an EFEM analysis of a simple passenger vehicle and compared the analysis with results reported in literature. Comparison between results in both tests produced good correlation. With the method validated, the structural-acoustic coupling characteristics of an aircraft cabin with two end plates were investigated. A wind tunnel test provided the fluctuating pressure load imposed on the exterior of a truncated conical aircraft cabin, and the structural-acoustic coupling characteristics of the aircraft cabin with two end plates have been investigated with the verified method. The detailed distribution of the flexural energies on the cabin surface and the distribution of acoustic pressures in the inner space of the cabin under the coupling condition were then obtained using the new method.