| Popis: |
Radiatednoise from various components is of increasing concern for today's automotive manufacturers. Traditionally, this analysis was usually performed with Boundary Element Method (BEM) software. Analysis results, although interesting in general, do not provide the design engineer with information on how to improve the design. Unfortunately, there is no sensitivity or optimization capability within any known BEM code, especially when coupled with a FEM code, which provides the vibration of the structure. This paper addresses the problem by describing the software developed by CDH, which combines the structural FEM analysis and optimization capability (MSC/Nastran, SOL200)with CDHBEM analysis code such that one can perform analysis andoptimization very quickly and efficiently. This approach is applied to an automotive air cleaner with internal acoustic domain, which is excited by pulsation of intake valves, which then vibrates and radiates noise. The radiated noise is then minimized at five predefined microphone positions in the far field. The maximum pressure was reduced by approximately 16 dB. |
