Abstract
When a multiplate wet clutch is idling, the drag torque occurs between disks. For the purpose of reduction in drag torque, the drag torque and visualization of a flow in the ditch of a clutch plate, were measured using the equipment which was modeled multiplate wet clutch in idling. The rotation speed and the ditch shape were changed. The rotation speed was 100,200,300rpm. The ditch shape was radial and slanting, and the ditch width was 1,2,4,8mm, respectively. As a result, the drag torque became lower in the case the ditch width was small, and the slanting shape. The velocity in a ditch will be one of the factors which have an influence on peripheral velocity and occur the drag torque fluctuate.
