Modelling of micro-geometry in elastohydrodynamic lubrication: Low-pressure valleys considerations
Résumé
Modelling deep valleys from surface micro-geometry in elastohydrodynamic lubrication has always been a challenge, since the solution of the Reynolds equation meets the cavitation condition Formula also in that part of the contact. Full numerical methods in principle can handle situations where the pressure is nearly zero, although the convergence can be affected. However, simplified approaches such as 'amplitude reduction' are in principle not designed to handle this problem. The present article shows some modifications to the amplitude reduction approach to handle pressures in deep valleys in a better way and compares with full-numerical solutions and with the unmodified amplitude reduction technique. At the end, some validity limits are established.