Multidisciplinary design of door inner belt weatherstrip for simultaneous reduction of wind noise and squeaking in electric vehicles

In electric vehicles (EVs), addressing noise, vibration, and harshness (NVH) has become pivotal, especially concerning external wind noise. To reduce wind noise, a door inner belt weatherstrip needs a high contact load, but this can lead to squeaking noise at the glass/weatherstrip interface. This study demonstrates a multidisciplinary design for the weatherstrip to tackle both issues. By increasing ethylene propylene diene monomer and ethylidene norbornene contents in the thermoplastic vulcanizate (TPV) by about 20 % and 70 %, respectively, the compression set was reduced from 35.4 % to 27.6 %. Concurrently, the TPV's damping properties improved, with a 25 % increase in loss modulus (323 MPa). Coated flocking surface of weatherstrip significantly reduced the friction coefficient by 80 % (from 1.75 to 0.30). In vehicle evaluations, the newly designed weatherstrip reduced the wind noise by 5 dB(A) and eliminated. This approach highlights the potential of multidisciplinary design in optimizing NVH for next-generation vehicles, including autonomous EVs and urban air mobility.