Improving sediment discharge efficiency in drip emitters via Tesla-inspired microchannels: PyFluent simulation and SHAP-based structural insights

Abstract

Sediment deposition is a critical factor contributing to emitter clogging and flow instability in drip irrigation systems, particularly under sediment-laden water conditions. At the micro-scale (10–1000 μm), flow and particle transport within emitter channels are governed by complex interactions involving confinement effects, turbulent structures, and particle–wall interactions. However, the mechanisms controlling sediment migration and removal remain insufficiently understood, and there is a lack of robust modelling tools to support emitter design under such conditions. In this study, a novel Tesla-inspired bidirectional microchannel was proposed to improve hydraulic performance and sediment discharge efficiency. A high-resolution Euler–Lagrange two-phase flow model was developed using PyFluent, integrating key physical processes including Schiller–Naumann drag, Saffman lift, turbulent dispersion, and rebound boundary conditions to simulate sediment behaviour at particle scale. Simulation results revealed that the inclusion of reverse-flow units significantly enhanced shear zones and vortex intensity, leading to a 97.18 % increase in turbulent kinetic energy (TKE, CFD simulation). Under different forward- and reverse-flow unit configurations, PSD and QSDV both decreased by 22.73 %–53.40 %. Variations under different channel widths and depths showed different ranges due to QSDV being normalised by volume (all CFD simulation results). Contribution analysis using SHapley Additive exPlanations (SHAP) identified hydraulic diameter and the number of forward-flow units as dominant structural factors influencing sediment transport through their effects on local energy dissipation and flow field reorganisation. These findings provide a physically interpretable and practically applicable modelling framework for optimising emitter design. This study proposed approach offers new insights into the coupling between microchannel geometry and sediment dynamics, supporting the development of anti-clogging strategies in drip irrigation systems using non-conventional water sources.