Over the past years, great effort has been made to reduce the noise level of the main sources in the passenger cell. However, previously masked noise sources have now become more annoying. Decreasing the global and modulation levels of the wiper system aerodynamic noise at speeds above 120 kilometers per hour has become an important topic. New aeroacoustic blades have been designed and tested in comparison with standard ones, in real road conditions. Several acoustic criteria for annoyance have been selected, and classification is now possible; transfer paths have also been studied, highlighting the influence of the windshield type. Acoustic measurement tests of the same type have been performed. Various thicknesses and damping materials of the windshield have been tested. The "flat blade" design acoustic characteristics are very satisfactory. When the flat blade and the "acoustic PVB" damping interlayer of the windscreen are associated, the aeroacoustic noise is nearly non perceptible. In this case, the influence of the side window is more apparent. The results also show that a good aeroacoustic wiper noise compromise can be found between weight decrease (smaller thickness) and acoustic performance using the "acoustic PVB". Comparison with numerical simulation shows good correlation.
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