Relationship among Mode Coupling, Friction velocity Slope and Stick slip Motion

Abstract:

Till now, four main frictional squeal mechanisms are highlighted including negative frictionvelocity slope theory, mode coupling theory, spragslip motion theory and stickslip motion theory. However, none of them can explain various frictional squeal phenomena fully. So it is very important to make clear the relationship among various mechanisms in order to unify the realization of friction induced vibration and noise. A nonlinear friction induced vibration lamped parameter model with two degree of freedoms is established, to simulate the friction induced vibration behaviour between a flexible body and a rigid body frictional pairs with singlepoint contact based on friction coefficient and frictionvelocity slope. By deduction and calculation, effect of friction coefficient and frictionvelocity slope on mode coupling instability is studied, according to which instability characteristics are summarized in four areas. For each area, stickslip motion, limit cycle and their dependence on working conditions are investigated. At the same time, it is pointed out that the change of system parameters result in the occurrence of Hopf bifurcation under the condition of positive frictionvelocity slope.