Nowadays, many car makers have tried to improve the vehicle fuel economy in various ways. The brake drag is one of well-known issues which related with the vehicle fuel economy and becoming important. In this paper, the new approach which could measure the drag on disc while vehicle driving, will be introduced. The current methods cannot measure dynamic drag in the vehicle, but can measure it with dynamometer in the laboratory. To measure dynamic drag in the driving vehicle, we devised the vehicle drag measuring equipment through theoretical approach and then validated it to correlate the vehicle drag measurement equipment with dynamometer testing one. Through the dynamic drag measuring method in the vehicle, this can overcome limitations of current drag measurement methods in dynamometer and vehicle and this contributes to reduce the brake drag on various conditions of the vehicle. Furthermore, this could help to improve fuel economy and CO2 emission.

Kong Young-hun, Park Choon-ki, Yoon Kyuwon, Nam Woung-chul, Min Chul-ki, Jeong Seok-tae -