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The development of new technologies that reduce engine size and improve performance, combined with the introduction of hybrid and electric vehicles, make tire noise critically important for the new generation of automobiles. Tire noise transmission into the passenger compartment can be classified as either air-borne or structure-borne sound. Both of these mechanisms are very complex to predict because tires are highly non-linear, subject to large static, dynamic and centrifugal loads; they suffer from impact, stick and slip forces; and the pumping of air in the tire grooves is complicated. Customers today demand more sophistication of products in terms of interior noise; thus, sound quality metrics have earned an important role during the design phase allowing human perception of noise to be predicted and improved with reduced cost in a way that addresses consumer preferences.

Predictions for vehicle interior noise and vibration levels can be made analytically using Statistical Energy Analysis (SEA), particularly for the middle and high frequency ranges. A SEA model can be effectively used together with some minimal baseline measurements to identify and predict changes to the dominant airborne and structureborne paths and to predict the effects that changes to the sound package or structure will have on these paths. Especially for relative changes in noise or vibration level, good accuracy is expected for acoustic or vibration response points such as driver's ear. An SEA model that has been validated with some baseline and various data, which may even come from a previous generation vehicle or component-level testing, can predict if a change to a sound package component will achieve a transmission target or if a proposed change will not be effective.

Transient Statistical Energy Analysis (SEA) is applied as an analysis technique and compared to measured data in this study. A transient SEA model for a door closure event is developed and compared to measured data to validate this model with measured acoustic and vibration responses. The validated model is then used to predict the effect of changes to component absorption, damping, stiffness, materials, and other properties. The basic theory of transient SEA and the transient SEA model used in the study are described, the validation between analytical model and measured data is shown, and the conclusions from the analysis of design changes to the vehicle components using this model are presented.