An equivalent NVH model of vehicle door seal strip and its application in door vibration problem

Abstract

The vehicle door seal strip has complex dynamic characteristics and is a critical component in the vibration and sound transmission of the vehicle system. However, in noise, vibration, and harshness (NVH) analysis, the seal strip is commonly simulated as a linear spring model, which results in inaccurate vibration and sound prediction. Thus, it is necessary to propose an alternative model, which allows characterising the complex dynamic behaviour of the seal strip accurately. In the present study, an overlay material model of rubber was encoded and embedded in ABAQUS with the UMAT subroutine. The overlay model was used in a seal strip finite element model validated by the quasi-static and dynamic measurements. By analysing the effects of frequency, amplitude, and pre-compression on the dynamic stiffness of a seal strip, an equivalent NVH model consisting of spring and damping elements was proposed. The proposed model was validated by comparing the simulated mode and vibration transfer function results with experimental ones. Using the spring model, the deviations of vibration transfer function with the experimental results are 37% and 8.3% at the first and second peaks, respectively. The corresponding deviations are only 4.6% and 2.6% employing the proposed model, demonstrating that the proposed model provides higher accuracy than the spring model. With the assist of the proposed model for vibration transmission analysis, a typical door vibration problem was successfully addressed, which proved the effectiveness of the equivalent model in engineering practice.