Application of Experimental Transfer Path Analysis and Hybrid FRF-Based Substructuring Model to Structure-Borne Noise

This paper describes a structure-borne noise reduction process that was developed using a combination of experimental and analytical methods. First, the major noise paths were identified using experimental Transfer Path Analysis (TPA). Next, FEA-Experimental modeling and forced response simulation were conducted using the Hybrid FEA-Experimental FRF method. The Hybrid FEA-Experimental FRF-Based Substructuring (FBS) model was used along with Operational Deflection Shape (ODS) and Modal Analysis. The Hybrid FEA-Experimental model consisted of an experimental FRF representation of the body and a finite element model of a sub-frame. The finite element of the sub-frame was created by using Altair HyperMesh from CATIA images and the dynamic analysis was carried out by using MSC Nastran. The natural frequency and frequency response function of the finite element sub-frame model were compared with that of a real sub-frame to determine the validity of applying the Hybrid FBS method. By comparing the results based on the finite element model with the predicted results of a real sub-frame, the usefulness of the Hybrid FBS application was confirmed. The Hybrid FEA-Experimental FRF model was then used to simulate the structure-borne noise reduction that would be obtained using a modified frame, prior to the availability of a prototype. Modified hardware testing was used as the final step in the process to confirm the results of the simulation.