Condition of Sealing Failure of a Car Side Window Glassrun Seal System under Wind Excitation

Abstract:

When a car is driven at high speed， there exists large pressure difference with strong pressure fluctuation between the car exterior and interior near the side window area， so the side window sealing system is likely to lose contact and thus generates leak noise， which can influence the interior sound quality seriously. The glassrun seal of the front side window was taken as the research object， with steady pressure penetration method and transient dynamic analysis， the condition of sealing failure occurrence was discussed. The main conclusions are as follows： with steady pressure penetration method， the critical static pressure difference is in the order of 10⁴ Pa. The influence factors of the critical pressure difference include glassrun shape， glass positioning， the rubber material parameters and the fixing manner etc. While with the transient dynamic analysis， as the window glass was offset with 0.2mm inward， the outer lip lost contact under the transient pressure difference in the order of 10³ Pa. The findings provide a meaningful reference for prevention of leak noise generation through improvement of sealing system design.

Key words:side window glassrun seal;leak noise;steady pressure penetration method;transient dynamic analysis