Waterfall CFD Simulation Using Two-Phase Flow, ANSYS Fluent Tutorial

Description

Description

In this project, the separation of laminar fluid flow from a surface easily seen in a natural Waterfall is investigated and analyzed using ANSYS Fluent software. We perform this CFD project and investigate it by CFD analysis.

The geometry and the mesh for this project are created inside Gambit. The geometry includes a mass-flow inlet, 3 pressure outlets, several symmetries and wall boundary conditions and 9 different partitions.

The mesh type used for this geometry is structured, and the element number is 626400.

Waterfall Methodology

Flow separation from a surface or separation of two-phase flows (natural waterfall) is one of the most important issues in fluid mechanics. Flow separation due to the specific shape of the geometry or flow can have positive or negative effects on its surroundings.

Therefore, it has always been tried to control this phenomenon as much as possible and investigate its possible effects and consequences. The VOF multiphase model has been enabled to simulate the two phases of water and air in this project.

Water enters the domain with a mass flow rate of 20Kg/s and falls due to the model’s geometric shape and gravity’s effect. Also, the RNG k-epsilon model is used to solve turbulent fluid equations.

Waterfall Conclusion

At the end of the solution process, two and three-dimensional contours related to the velocity, pressure, streamlines, and volume fractions inside the domain are obtained. The water volume fraction contour clearly shows how the water flow will behave due to the effect of gravity as it reaches a ledge.

Moreover, if velocity vectors are viewed with care, it can be seen that due to the surface tension that exists between water and air, the water jet produced by the waterfall will cause the airflow to form a subtle flow near the free surface of the water, which its effect can also be seen in the turbulent viscosity contour.