A CFD model is presented to understand internal circulation vortices induced in spherical and ellipsoidal drops by an external flowing immiscible liquid and the ensuing effect on interfacial mass transfer. The model is validated with experimental data reported in literature for spherical drops. Validated model is used for detailed parametric analysis to understand the effects of relative velocity, droplet diameter and physical properties on Sherwood number. Resulting data are regressed to propose a correlation to estimate Sherwood number for spherical drops. Simulations for symmetrical ellipsoidal drops reveal the presence of secondary circulation vortex in some cases. The secondary circulation vortex is found to enhance Sherwood number significantly. The correlation for estimating Sherwood number for spherical drops is modified to propose correlations for symmetrical ellipsoidal drop with and without secondary circulation vortex. Finally, asymmetric ellipsoidal drops are also studied to understand the effect of shape on internal circulation pattern and Sherwood number.