TY - GEN

T1 - Condensing structural finite element meshes into coarser acoustic element meshes

AU - Fahnline, John B.

N1 - Publisher Copyright:
© 1995 American Society of Mechanical Engineers (ASME). All rights reserved.

PY - 1995

Y1 - 1995

N2 - The sound power radiated by a vibrating structure (with negligible fluid loading) is typically computed in two steps. First, a finite element mesh of the structure is constructed, and the structural vibrations are computed. The finite element mesh is then converted to a surface mesh, and the sound power output is computed using the boundary element method. In many cases, the acoustic analysis is computationally inefficient because the structural finite element mesh is much denser than required for the acoustic calculations, leading to the solution of a large, fully populated, matrix equation. It is shown that the efficiency of the acoustic analysis can be significantly increased by condensing the structural finite element mesh into a much coarser acoustic element mesh, where the surface meshes of several structural elements are combined to form a single acoustic element. This condensation- becomes possible when the boundary condition for the acoustic analysis is written in terms of elemental volume velocities instead of nodal velocities. An example is given in which sample computation times are tabulated, and the accuracy of the numerical calculations are assessed.

AB - The sound power radiated by a vibrating structure (with negligible fluid loading) is typically computed in two steps. First, a finite element mesh of the structure is constructed, and the structural vibrations are computed. The finite element mesh is then converted to a surface mesh, and the sound power output is computed using the boundary element method. In many cases, the acoustic analysis is computationally inefficient because the structural finite element mesh is much denser than required for the acoustic calculations, leading to the solution of a large, fully populated, matrix equation. It is shown that the efficiency of the acoustic analysis can be significantly increased by condensing the structural finite element mesh into a much coarser acoustic element mesh, where the surface meshes of several structural elements are combined to form a single acoustic element. This condensation- becomes possible when the boundary condition for the acoustic analysis is written in terms of elemental volume velocities instead of nodal velocities. An example is given in which sample computation times are tabulated, and the accuracy of the numerical calculations are assessed.

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U2 - 10.1115/DETC1995-0455

DO - 10.1115/DETC1995-0455

M3 - Conference contribution

AN - SCOPUS:33744568217

T3 - Proceedings of the ASME Design Engineering Technical Conference

SP - 641

EP - 646

BT - 15th Biennial Conference on Mechanical Vibration and Noise - Acoustics, Vibrations, and Rotating Machines

PB - American Society of Mechanical Engineers (ASME)

T2 - ASME 1995 Design Engineering Technical Conferences, DETC 1995, collocated with the ASME 1995 15th International Computers in Engineering Conference and the ASME 1995 9th Annual Engineering Database Symposium

Y2 - 17 September 1995 through 20 September 1995

ER -