습식 클러치 설계를 위한 실험 변수에 따른 드래그 토크 특성 평가

Abstract

As environmental and energy issues increase, energy efficiency is of great significance in the automobile industries. Drag torque of a wet clutch in an automatic transmission system is one of the causes of energy loss. In this work, the drag torque characteristics of a wet clutch as a function of rotational speed was experimentally investigated with respect to the test parameters such as automatic transmission fluid (ATF) temperature and flow rate, clearance between friction disk and separator, and the number of disks in the test system, using two different friction materials. Drag torque was found to decrease with increasing ATF temperature as a result of the decrease in viscosity. Also, drag torque decreased as the clearance between friction disk and separator increased. In addition, the drag torque increased along with the delay in the generation of maximum drag torque as the ATF flow rate increased. Furthermore, it was observed that drag torque increased with the increase in the number of disks in the test system. The drag torque characteristics as a function of rotational speed may be dependent on the friction materials. The results obtained from this work may aid in the design of wet clutch system to enhance performance.