Numerical analysis of the coupling between frictionally excited thermoelastic instability and thermal buckling in automotive clutches

Abstract

The coupling between thermal buckling and thermoelastic instability in clutch disks is investigated using a series of finite element analyses. The temperature distributions are first obtained from the eigenmodes based on the classical thermoelastic instability analyses. The critical buckling temperatures along with the buckling deformation modes of the clutch disk under prescribed temperature fields are subsequently computed using the commercial finite element software ABAQUS. The effects of multiple parameters including sliding speed, coefficient of friction and boundary conditions have been investigated. It is concluded that there exists a strong coupling between thermoelastic instability and thermal buckling, and that the thermoelastic instability induced unstable temperature modes can significantly alter the input temperature profiles for thermal buckling, and thus the critical buckling temperatures. In addition to the effects of axisymmetric thermoelastic instability modes (i.e. banding modes), thermal buckling induced by the nonaxisymmetric thermoelastic instability modes (i.e. focal hot spots) is also tentatively studied.