A Case Study on Development of a Porous Ducted Air Induction System Solution for a new Chrysler vehicle

摘要

Vehicle interior sound level and quality are two very important considerations for a new vehicle buyer in the marketplace. In this paper, the development effort of a porous-ducted induction system solution to achieve the targeted in-vehicle NVH performance is presented. First, early development prototypes of a new vehicle model indicated a large gap to target for interior sound levels. After testing and confirming high snorkel levels to be the root-cause, various AIS design concepts involving snorkel positioning duct material of the dirty-side duct were explored, taking into consideration the acoustic sensitivity and transfer function of the vehicle. After several iterations of testing, an alternate porous ducted design concept with a re-located snorkel was proposed to meet the in-vehicle NVH target levels. This concept was accepted and further optimized using GT-Power, a commercially available simulation tool that predicts AIS noise. In this case study it is concluded that snorkel positioning combined with a strategically placed porous duct is very effective in reducing air induction noise inside the cabin. Also, it is concluded that an accurate simulation model can be used to optimize and evaluate different design concepts up front, and assist with developing timely solutions for a production launch of a new vehicle.