Abstract: A complete numerical solution for the transient thermoelsatohydrodynamic lubrication problem of an involute spur gear is obtained by using simplified multigrid method. The lubricant is assumed to be Newtonian fluid and the surface roughness of gear teeth is ignored. The load is first assumed to be carried by either two pairs of gear teeth or by only one pair. This transition is modelled as a step variation of the load by simplifying the experimental load spectrum. The results show that thermal effects can strongly influence the approach and recess point film thickness. The maximum pressure, the maximum friction coefficient and the highest film temperature all occur in the vicinity of pitch point. The minimum film thickness usually occurs at the approach point except reduction ratio equals to one. The film temperature and the friction coefficient are influenced by the slip ratio, velocities and the load.

Key words: Multigrid method, Involute spur gear, Transient thermoelastohydrodynamic lubrication