Development of a new interlayer for laminated glass to improve sound quality within cars

摘要

The most important implications of glass concerning NVH within cars are booming noise and wind noise. Booming noise is dealing with low frequencies (below 200 Hz), wind noise with high frequencies (glass contributes above 1000 Hz). All laminated glazings use standard PVB, which has not been developed for acoustic purpose. The replace it, the properties of a new interlayer have been adjusted by the use of modelisation: finite elements for low frequencies, specially developed computational model and SEA for medium and high frequencies. The influence of glazings had to be studied concerning booming by coupling of windscreen modes to cavity modes and coincidence effect on income of aerodynamic noise through side lites. Measurements under running conditions have been done, and psychoacoustic parameters had to be introduced. Special acoustic interlayer has been found to have great interest.