SUMMARYIn this paper three-dimensional lubrication ow of grease is analysed numerically. The lubrication ow conÿguration is formed by two ellipsoid rollers. The load is assumed to be light enough for the lubrication mode to be purely hydrodynamic. The uid behaviour is modelled using the HerschelBulkley model, and a two-dimensional modiÿed Reynolds equation is derived. The numerical solutions are obtained by using a hybrid spectral=iterative technique and the Galerkin projection scheme. The e ects of the material and geometrical parameters on pressure distribution are emphasized in the study. The investigation is conducted for a situation where the two ellipsoids are fully immersed in a grease lubricant. The e ect of the geometry on the pressure distribution is determined by varying the ratio of the semi-axes and the minimum gap of the two rollers, respectively. The e ect of the material parameters is examined by varying the power-law index and yield stress. It is found that the pressure distribution is strongly in uenced by the shape of the rollers, the size of the minimum gap of the rollers and the rheological parameters.