Effect of friction on dynamic energy dissipation in granular chain
In this work,we used a one-dimensional particle system with finite length to study the effect of friction on energy propagation in granular materials.Normal contact forces acting between particles follow the nonlinear Hertz contact law,while the tangential shear forces acting between particles and plates follow the Mindlin shear force law.To simulate the wave propagation through the particle chain,a center difference method is applied,and the kinetic equation is directly solved by the discrete element method.With this model,we observed a primary solitary wave produced when a striker collides with the second particle,and the wave dissipates nonlinearly with the travelling length even when tangential frictional forces between particles and rigid boundary are very small.Energy dissipation in granular materials can be deduced by comparing the amplitude and velocity of the main solitary wave and the maximum contact force between particles.The results show that the primary solitary wave will dissipate rapidly and eventually disappear within a finite distance in the one-dimensional chain,even though the frictional forces are much smaller than the average normal contact forces between particles.This finite distance depends on the frictional forces.As the wave propagates,three stages,including nonlinear collision stage,transition stage,and friction-collision mixed stage,can be distinguished using the relation between wave speed and maximum contact force.
万方数据
维普
