Description

The present problem simulates a counterflow in a canal using ANSYS Fluent software. We perform this CFD project and investigate it by CFD analysis.

This work investigates fluid flow behavior when exposed to a flow in the opposite direction.

In this simulation, water flows from the canal into a rectangular section horizontally, and at the same time, another flow of water from a pipe lying on the floor of the same canal, horizontally but in the opposite direction of the initial flow into the canal.

The present model is designed in three dimensions using Design Modeler software.

The model's geometry consists of a channel with a rectangular cross-section with a length of 8 m and a rectangular cross-section with a length and width of 3 m and 1 m. At the bottom of the canal, a 4 m long pipe and 0.05 m in diameter is lying down.

The meshing of the model has been done using ANSYS Meshing software. The element number is 256899.

Counterflow Methodology

The inlet water flow velocity from the rectangular section of the channel is defined as 0.3 m.s-1, and the inlet water flow velocity to the pipe is defined as 2 m/s.

Also, the spaces above this canal are considered special spaces for open-air flow, so the boundary condition of inlet pressure with relative pressure equal to zero is used.

Therefore, since the computational domain of the present model has two different types of fluids, including water and air, the multi-phase VOF model is used for the current simulation. Furthermore, the standard k-epsilon model is used to solve turbulent fluid equations.

Counterflow Conclusion

At the end of the solution process, two-dimensional and three-dimensional contours related to the pressure, velocity, and volume fraction of each of the air and water phases are obtained.

As seen in the air volume fraction contour, the injection of air in the opposite direction of water causes a locally reduced water volume fraction.