Thermoelastic behaviour of an automatic transmission clutch with a 'finger' piston involving thermoelastic instability. (7th November 2008)

• Record Type: Journal Article
• Authors: Zagrodzki, Przemyslaw; Zhao, Wenping
• Is Part Of: International journal of vehicle design. Volume 48:Number 1/2/(2008)
• Page Start: 97
• Page End: 113
• Publication Date: 2008-11-07
• Subjects: friction clutch -- multidisk clutch -- automatic transmission -- thermoelastic instability -- hot spots -- temperature -- stress -- finite element method -- FEM -- vehicle design -- finger piston; Motor vehicles -- Design and construction -- Periodicals; 629.231
• Languages: English
• ISSNs: 0143-3369

Abstract

An important practical case of frictionally excited Thermoelastic Instability (TEI) in a wet multidisk friction clutch of an automotive transmission with so-called finger piston is investigated. Advanced finite element model of thermoelastic multi-surface contact problem is used. Theoretical results are verified experimentally. The study shows that finger piston used in transmission clutches can trigger unstable thermoelastic behaviour which leads to severe hot spots. In search for solution to this problem two alternative pack designs were investigated: pack with single-sided friction plates and an inverted double-sided pack. Simulations and experiments consistently show that the two alternative designs effectively mitigate hot spots.