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Wind noise is a major problem in automobiles today. It is especially significant since powertrain and tire noise continue to diminish and quieter electric vehicles are on the horizon. The Wind Noise Modeller is an analytical tool that accurately computes sound pressure levels (SPL) at the driver's ear caused by wind noise. Using Statistical Energy Analysis (SEA), it accounts for the sound radiated both from the vibrating side glass and through the door seals. Incorporated into an EXCEL spreadsheet that runs on a PC or workstation, it automatically computes, plots, and tabulates both linear & A-weighted SPL, and compares it to user-supplied experimental data. It can quickly evaluate the effects of vehicle changes on the resulting noise level. When coupled with reliable CFD computations, it can be used very early in the design process to help minimize wind noise. This should greatly reduce wind tunnel tests needed for wind-noise estimations.

The current ability of the Virtual Aerodynamic/ Aeroacoustic Wind Tunnel to predict interior vehicle sound pressure levels is demonstrated using an automobile model which has variable windshield angles. This prediction method uses time-averaged flow solutions from a lattice gas CFD code coupled with wave number-frequency spectra for the various flow regimes to calculate the side window vibration from which the sound pressure level spectrum at the driver's ear is determined. These predictions are compared to experimental wind tunnel data. The results demonstrate the ability of this methodology to correctly predict wind noise spectral trends as well as the overall loudness at the driver's ear. A more sophisticated simulation method employing the same lattice gas code is investigated for prediction of the time-accurate flow field necessary to compute the actual side glass pressure spectra.