A novel non-dimensional investigation of slurry transport in modular annular jet pump

Abstract

Annular Jet Pumps are widely used for slurry transport in mining and dredging applications. However, their performance under dense slurry conditions is governed by complex multiphase flow and turbulence interactions that are not yet fully understood. This study presents a novel non-dimensional, plane-wise investigation of slurry flow in a modular AJP, evaluated at three critical planes (inlet, throat radial centre, and outlet), along the axial length, and along the throat wall. A Mixture Model Approach (MMA) combined with the realizable k–ε turbulence model is employed to simulate water–sand slurry flow. Interphase slip is captured using the Schiller–Naumann drag model. A comprehensive parametric study is conducted for primary fluid flow rates ranging from 6–10 m³/h, convergence angles of 21°–27°, sand volume fractions of 0–40 %, and particle sizes between 200–1000 µm. Three non-dimensional parameters (Reynolds number, Slip number, and Viscosity ratio) are analyzed, with the viscosity ratio introduced as a novel metric to quantify the balance between slurry rheology and turbulence-induced momentum transport. A high-quality structured mapped mesh is used, and mesh independence is confirmed with deviations below 2.19 % for key parameters. The results demonstrate that Slip number and Viscosity ratio reveal distinct and consistent trends in phase interaction, turbulence modulation, and energy dissipation, particularly within the throat and diffuser regions. These findings provide quantitative insight into slurry transport mechanisms in AJPs and establish a physics-based framework for performance assessment and future optimization of slurry-operated jet pumps.