Description

This project uses ANSYS Fluent to simulate counterflow in a canal and analyze the resulting fluid behavior. The setup features a main water stream moving along the canal while a second stream is injected in the opposite direction from a floor-mounted pipe.

The 3D geometry (DesignModeler) represents a straight channel 8 m long with a 3 m × 1 m rectangular cross-section. A 4 m long pipe of 0.05 m diameter lies along the canal floor. Meshing (ANSYS Meshing) yields 256,899 elements. A transient solver is used.

Counterflow Methodology

The main channel inflow velocity is 0.3 m/s, while the pipe issues flow at 2 m/s in the opposite direction. The region above the water surface is open to air; a pressure inlet boundary with 0 Pa gauge represents ambient conditions.

Because both water and air are present, a VOF multiphase model is employed, with the standard k–ε model for turbulence.

Conclusion

Post-processing provides 2D and 3D fields of pressure, velocity, and phase volume fraction for water and air. The opposing jet perturbs the free surface and entrains air, producing zones with a locally reduced water volume fraction where the counterflow interacts with the main stream.