ABAQUS声学分析-acoustics-lecture.ppt

Copyright 2005 ABAQUS, Inc. Structural-Acoustic Analysis with ABAQUS Additional Examples Lecture 6 Copyright 2005 ABAQUS, Inc. L6 . 2 Structural-Acoustic Analysis with ABAQUS Overview ? Sloshing ? Effect of Surface Treatments on Room Acoustics ? Nonlinear Structural Behavior ? Coupled Piezoelectric and Acoustic Analysis ? Acoustics of a Truck Cab: Fully Coupled Analysis ? Acoustics of a Truck Cab: Sequential Analysis ? Summary Copyright 2005 ABAQUS, Inc. Structural-Acoustic Analysis with ABAQUS Sloshing Copyright 2005 ABAQUS, Inc. L6 . 4 Structural-Acoustic Analysis with ABAQUS Sloshing ? Spherical acoustic radiation in Mode 1 – Reference: Junger, . and Feit, D., Sound, Structures, and Their Interaction , MIT Press, pp. 200-203, 1972. – Physical Description: ? A steel ( ??7800 kg/m 3 , E?210 GPa, ?? ) spherical shell of radius 1 m and thickness m is immersed in an infinite volume of air ( ? = kg/m 3 , K?128000 Pa, c?320 m/s). ? The sphere is driven as a rigid body to excite mode 1 using the *BOUNDARY, TYPE=DISPLACEMENT option. ? A frequency range of 10 Hz to 204 Hz, corresponding to ka ~ to is analyzed using *STEADY STATE DYNAMICS, DIRECT . ? Nonconforming shell ( S8R ) and acoustic infinite element ( ACIN3D4 ) meshes are used. ? Fluid-solid coupling through use of the *TIE option. Copyright 2005 ABAQUS, Inc. L6 . 5 Structural-Acoustic Analysis with ABAQUS Sloshing ? Meshes (shells in orange) Copyright 2005 ABAQUS, Inc. L6 . 6 Structural-Acoustic Analysis with ABAQUS Sloshing ? Pressure magnitudes at Hz Copyright 2005 ABAQUS, Inc. L6 . 7 Structural-Acoustic Analysis with ABAQUS Sloshing ???????????? 2 2 6 22 1 1 2222 2 (2 ) ka ka P c u ka ka ka ?? ??? ??? Pressure magnitude results freq (Hz) ka Node 1776 Node 35 Analytical