Slip Energy Evaluation for a Conventional Friction Clutch

The importance of clutch in a vehicle’s performance is not new to the automotive, commercial or agricultural sectors, so is the importance of the clutch life when it comes to the durability of a vehicle. In process of making the machines more and more efficient, one can observe a steady reduction in the overall mass of the vehicle and the parts in it. While the parts were heavier, and the friction lining surfaces were more than adequate, the life of clutch has been the best. But with reduction of the overall mass’, the energy has lesser amount of reservoir to dissipate and is being liberated in the form of heat, rising the overall temperatures. This leads to an early wear or even a burn in the clutch. In such scenario, it is necessary to estimate accurately the energy dissipation through a defined cycle to understand the clutch performance. Although different methods exist to evaluate energy, most cases include obtaining a high amount of sophisticated data. This paper discusses a simpler and efficient approach to estimate the clutch slip energy. Theoretically, the energy dissipated by any friction force is the force multiplied by the amount of slip that friction has caused. Using this concept, we can compute energy with real-time frictional torque and the amount of slip angle. The clutch parameters are measured (as a set) where we can have the relation between clamp-load and the clutch release bearing travel from which we can calculate the amount of frictional torque acting. The slip angle can be measured with angular speed signals from flywheel and transmission input shaft coupled with the release bearing travel data. Using these two, one can accurately estimate the energy dissipated through a particular launch cycle.