The high efficiency of hole cleaning is essential and critical for drilling horizontal wells. In this study, the effects of four-lobed drill pipe on drill cuttings transport behaviors are examined using a coupled Computational Fluid Dynamics and Discrete Element Method approach. The drill cuttings concentration in annulus is used as the primary quantitative parameter, and the efficiency of hole cleaning is evaluated. Numerical results show that the curvature wall of four-lobed drill pipe by driving secondary motions and induces a local swirling flow, which promotes the transport of drill cuttings and significantly improves the hole cleaning performance. Compared with the conventional drill pipe, the hole cleaning efficiency of four-lobed drill pipe is improved by 89.7% on average, and the average kinetic energy of drill cuttings increases by one order of magnitude. These results are expected to provide a useful strategy for local hole cleaning when drilling horizontal wells. (C) 2020 Elsevier B.V. All rights reserved.