Combination Analysis of Operational TPA and CAE for Extraction of High Contributing Vibration Mode to Vehicle Interior Road Noise

In this study, we developed a method which extracts important CAE vibration modes giving large influence to vehicle interior noise at the operational condition. Both operational transfer path analysis (OTPA) method and CAE technique were utilized in this method. A simple vehicle model was employed in the test and random noise was given at each tire to make running situation on a rough road. We then measured vibration acceleration signals at multiple points of the body panel and vehicle interior noise simultaneously for carring out OTPA. Subsequently, high contributing principal component mode of the body to the interior noise was analyzed by modified OTPA method which calculates principal component contribution. In addition, vibration modes of the target structure were obtained by CAE. After then, a few high contributing CAE vibration modes were extracted from a lot of modes by evaluating the mode shape similarity between the high contributing principal component mode and the CAE vibration mode. In the experimental verification, the interior noise level could be decreased very well by applying an intensive countermeasure to the high contributing vibration mode using CAE response analysis and the proposed method was verified to be able to choose high contributing CAE modes correctly.