Method for Estimating Temperature of 4WD Coupling Device Wet Clutches in Severe Operating Condition

Howon Seo, Suk Won Cha, Wonsik Lim, Sangchul Han

Abstract
Due to the increasing demand for multi-purpose vehicles, there has been a noticeable increase in the sales volume of 4-wheel-drive (4WD) vehicles such as Sports Utility Vehicles (SUV). Most 4WD vehicles are equipped with a coupling device which transfers driving power to the rear drive shaft. In some severe operating condition, wet friction clutches in a coupling device generate enormous heat from friction and cause a sharp temperature increase. Excessive heat can cause thermal damage on the surface material of the clutch. Therefore, a method estimating temperature of the clutch is required to avoid thermal damage. This study suggests a method for estimating temperature of clutch. A full car dynamic model was constructed to simulate the severe driving conditions of a 4WD vehicle and the results of the experimental validation of the temperature estimation model are presented