Abstract: Under high speed mode, external aerodynamic load of cars leads to vibration, noise and poor sealing performance. It is necessary to establish the model of windows in order to study the sealing performance considering fluid-solid coupling effect. However, it is difficult to build the constraint model of windows, which obstructs the analysis and optimization of the window sealing system due to the hyper-elastic character of material and non-uniform geometrical cross-section, as well as the complicated contacting relationship between seals and the glass. According to principle of functional equivalence, the effect of channel guide-glass is equivalent to variable stiffness elastic constraint. On the basis of compression load deflection (CLD) tests, the CLD of unilateral lips is synthetized together to represent the bilateral sealing effect, considering the thickness of glasses. Using car’s front window as an example, its window sealing model is established based on the proposed method and the deflection under concentrated load is calculated. The results of quantitative analysis agree with that of static structure experiments well, which shows the effectiveness of window model based on nonlinear stiffness fitting. It can support sealing optimization design for high speed condition.

Key words: automotive window, compression load deflection, constraint modeling, nonlinear stiffness