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A mathematical model was developed to evaluate design options for control of road noise transmission into the interior of a passenger car. Both air-borne and structure-borne road noise over the frequency range of 200-5000 Hz was able to be considered using the Statistical Energy Analysis (SEA) method. Acoustic and vibration measurements conducted on a laboratory rolling road were used to represent the tire noise “source” functions. The SEA model was correlated to in car sound pressure level measurements to within 2-4 db accuracy, and showed that airborne noise dominated structure-borne noise sources above 400 Hz. The effectiveness of different noise control treatments was simulated and in some cases evaluated with tests.

A simple mathematical model was developed and experimentally validated to evaluate how the materials and construction of an automobile tire affect its vibration-radiated noise performance. The mathematical model uses Statistical Energy Analysis (SEA) with modal joint acceptance formulations for wavespeed and radiation efficiency of orthotropically-stiffened and pressurized cylindrical shells. Experimental validation of the model included wavenumber decomposition to determine the dispersion characteristics of an inflated, non-rolling tire in the laboratory. The model is used to conduct a preliminary study into how the various tire constituent materials and construction parameters influence the vibration-radiated noise performance.