Erosion in an Obstruction Channel: DPM

Erosion in an Obstruction Channel Using DPM, ANSYS Fluent Training

Description

This project simulates erosion within an obstruction channel using ANSYS Fluent's Discrete Phase Model (DPM), modeling the flow of impure water carrying sand particles and examining how these particles impact channel surfaces over time. The simulation models 1 mm diameter sand particles suspended in high-velocity water flow, tracking their trajectories and the resulting impact on channel surfaces, with particle residence time analyzed alongside the erosion patterns it produces.

The geometry was designed in Design Modeler and meshed using a structured grid of over 1 million quad elements, with the solver configured for steady-state conditions to capture the erosion/accretion phenomena central to this analysis.

Methodology

Particle-induced erosion was captured using DPM with two-way coupling, accurately representing the interaction between the sand particles and the surrounding water flow. The channel's obstruction geometry significantly shapes both the flow pattern and the resulting erosion behavior, generating high-velocity regions reaching up to 93.5 m/s at points where the flow is forced around the obstacle — these accelerated zones directly correlate with the locations most prone to erosion.

Several established erosion theories — including the Oka, McLaury, and Finnie models — were applied to provide a comprehensive assessment of erosion behavior under these flow conditions, each offering a different perspective on how particle impact translates into surface wear.

Conclusion

The results reveal a clear correlation between the channel's velocity and pressure gradients and the resulting erosion hotspots, with the obstruction's geometry playing a central role in determining where wear concentrates most heavily. By combining detailed particle trajectory tracking with multiple erosion models, this simulation provides a comprehensive picture of long-term wear behavior in obstructed channel flows — directly applicable to pipeline design, hydraulic machinery wear prediction, and maintenance planning across industries such as oil and gas, water treatment, and mineral processing.