This paper demonstrates that our extended smoothed particle hydrodynamics (SPH) model can successfully simulate multiphase flow in a Humphrey spiral concentrator (HSC) with two phases: powder and water. The powder phase in the model was assumed to be a continuum, as the spacing between particles in this state is much smaller than the typical length scale of flow. Further investigation was conducted on the influences of various design factors of the HSC, including the descent angle and curvature profile of the trough, during the separation of a binary mineral particle mixture. The model was validated by comparing the simulated results with the experimental results of Loveday and Cilliers (1994) as well as those of a novel lab-scale-experiment using a miniature of the HSC. The proposed SPH model accurately simulated dusty liquid flow in the HSC in both cases with an acceptable degree of accuracy relative to the experimental results. These studies are expected to be useful in future optimizations of HSC design and operating conditions. (C) 2017 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.