Transient elastohydrodynamic lubrication analysis of an involute spur gear using couple-stress fluid

Abstract

A complete numerical solution to the transient elastohydrodynamic lubrication (EHL) problem of an involute spur gear is obtained under isothermal condition. The lubricant is assumed to be couple-stress fluid and the transient Reynolds equation for the compressible couple-stress fluid is derived using Stokes theory. The EHL characteristics computed for couple-stress fluids are found to have strong dependence on couple-stress parameter. Significant increase in minimum film thickness due to couple-stress fluid is observed. Also, it is found that couple-stress fluids tend to smoothen the variation of film thickness along the line of action caused by transient effects.