LAUSR

The article presents an efficient novel numerical method to investigate overrolling (with slip) of transient EHL line contact problem with surface asperities. Jacobian free Newton–Krylov subspace (JFNK) method is used for the solution of discretized transient Reynolds and film thickness equations. The dense nonsymmetric large system of linear equations is solved using an iterative strategy based on wavelet based preconditioned generalized minimal residual (GMRES) algorithm incorporating a line search scheme to archive global convergence. The focus is on highly loaded (with Hertz pressure 2GPa) line contact EHL problem to obtain pressure and film profiles as functions of the slide to roll ratio. The nonsynchronization of pressure and film profiles (especially at dent locations) is found explicitly which is more pronounced as the dent approaches the contact central region and moves towards the exit. Leading/trailing of film profile is observed as the dent (attached with an upper surface) moves slower/faster compared with average speed (of surfaces). Also, there is an increase (in height as well as a spread) of Petrusevich pressure spike as dent moves through the contact region towards the exit. For the waviness attached with the upper surface, the pressure and film profiles are obtained again as functions of a slide to roll ratio. Pressure profiles are invariant with respect to this parameter whereas film profiles are entirely different in all these cases. The proposed method, with projection features, captures salient aspects of the model problem with much lesser degrees of freedom compared with conventional schemes.