A fundamental understanding of the impact of different hydrodynamic, scaling, and geometric conditions on cuttings transport are essential for successful wellbore drilling. This study presents a validated computational fluid dynamics (CFD) model for investigating cuttings transport phenomena in deviated wells with Herschel Bulkley drilling fluids at different drilling conditions. A CFD model was developed and validated with our experiments conducted in the TAMUQ flow loop (5-meter horizontal length, 4.5in. X 2in.) and open literature. The Eulerian-Eulerian approach simulated solid-liquid laminar and turbulent flow in annular geometry utilizing hexahedral mesh under transient conditions. It was observed that the optimum range for efficient hole cleaning is from 0-200 RPM, and increasing RPM above 200 will have a marginal impact on improving hole cleaning. Cuttings size of 0.004 m was determined to be the critical size for solid particle removal. Hole enlargement has a hugely adverse effect on the fluid-carrying capacity due to the reduction of fluid velocity in the enlarged section and cuttings concentrate. Poor hole cleaning signs were observed with increasing cuttings density and wellbore inclination between 45-60 degrees. Copyright © 2022 by ASME.