Simulation of Wet Clutch Engagement on Electronically-Controlled Limited-Slip Differential (LSD) With Consideration of Degraded Clutch Performance

A wet clutch is an integral part of the electronically controlled limited slip differential (eLSD) [1]. In this study, an eLSD model is constructed based on Deur et al.’s dynamic wet clutch model [2]. First the eLSD model including key dynamic equations and parameter values is discussed. The main culprits of clutch shudder include the negative slope of friction coefficient vs. slip speed curve, which is often caused by oil oxidation due to heat or an improper amount of friction modifier among others, and glazing of the friction linings [3,4]. In the second part, consequences of improper lubrication and glazed friction material during launch control of a vehicle equipped with eLSD will be studied based on simulations with lubrication data provided in [3]. The simulation results show that the combined effects of oxidized ATF and glazed friction material can cause clutch shudder.