Evaluation of Unsteady Flow Phenomena Induced by the Tailgate Gap of a Production Car Using Simulations and Experiments
The gaps at the tailgate of passenger cars can play an important role in the generation of wind noise. Depending on the particular geometry, flow separation and vortices may occur that cause pressure fluctuations perceived by the passengers. The underlying aeroacoustic effects can be hard to predict and extensive testing is required to eliminate disturbing wind noise.
In the present work, the acoustic characteristics of an exemplary sedan car are investigated with a focus on the rear end. Different sealing concepts for the tailgate gap are evaluated using wind tunnel measurements and computational fluid dynamics. The study incorporates interior-noise spectra and a deeper analysis of pressure fluctuations around the rear glass panels.
The results imply that the numerical method is suitable to predict the performance of different sealing concepts if small gaps and structures are sufficiently resolved. Furthermore, the simulation provides insight to physical mechanisms and allows the localization of sensitive areas.
We gratefully acknowledge the support of Exa GmbH and the fruitful collaboration with the FKFS Forschungsinstitut für Kraftfahrwesen und Fahrzeugmotoren Stuttgart.
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