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Statistical Energy Analysis (SEA) is a tool for estimating the response of complex dynamic systems at high modal density. This tool is seeing ever wider application in a range of industries, including aerospace industry, marine industry, and building trades. The automotive industry is beginning to explore the application of SEA to high frequency vehicle acoustic design. The SEA model of vibrational power transmission has a direct analogy to thermal power transmission (diffusion). As thermal power flow is proportional to temperature difference, vibrational power flow is proportional to modal energy difference. In this paper the thermal analogy is exploited to visualize the SEA results. This is accomplished by color coding a finite element representation of the structure. In this paper, the thermal analogy is used to correlate test data with SEA model results. This is accomplished by constructing a test based modal power thermogram.

For vehicle interior noise abatement and noise treatment, it is desirable to quantitatively determine sound power contribution from each vehicle component because: (1) Sound packages can be designed with maximized efficiency if sound power contribution into a vehicle is known; (2) Acoustic leakage inside a vehicle can be determined by comparing sound power contributions from adjacent vehicle components; and (3) Sound power flow information can be used to verify Statistical Energy Analysis (SEA) model. Simple sound pressure measurement does not produce any information about sound power flow and is unsuitable for these purposes. This paper describes an in-situ determination of sound power contribution inside a vehicle using sound intensity measurements. Sound power contribution from each vehicle component was determined for engine noise at idle speed. Acoustic leakage in the vehicle was also determined.

Statistical Energy Analysis (SEA) is being actively pursued in the automotive industry as a tool for vehicle high frequency noise and vibration analysis. A D-class passenger car SEA model has been developed for this purpose. This paper describes the development of load cases for the SEA model to simulate road noise on rumble road. Chassis roll test with rough shells was performed to simulate rumble road noise. Sound radiation from tire patch and vibration transmission through spindles were measured to construct the SEA load cases. Correlation between SEA model predictions and measured data was examined. Test and SEA result comparisons have shown that simulation of airborne road noise requires only a trimmed body SEA model, while simulation of structure-borne road noise may require SEA modeling of chassis components.