Wind Tower (2-D) CFD Simulation Tutorial

Description

In this project, the conjugate heat transfer (CHT) of airflow in a simplified 4-story wind tower is investigated by ANSYS Fluent software. We perform this CFD project and investigate it by CFD analysis.

The project’s 2D geometry is designed in the Design Modeler, and the computational grid is generated using ANSYS Meshing software. The mesh type is structured, and the element number is 6375.

Wind Tower Methodology

In this problem, conjugate heat transfer (a combination of convective and conductive heat transfer) is modeled inside a wind tower. The diagonal wall on the computational domain’s right side has a temperature of 305K with a heat generation rate of 1000W/m³.

The airflow enters through the inlet boundary on the top left side of the wind tower with a velocity of 12m/s and a temperature of 300K. The air enters each of the 4 levels of the building to ventilate and reduce the temperature.

Also, to simulate natural convection, gravity is enabled in the Y direction, and the Boussinesq model is used to calculate the air density changes due to temperature change (the initial density of air is set to 1.225Kg/m³, and its thermal expansion coefficient is set equal to 0.00331 1/K)

Wind Tower Conclusion

At the end of the solution process, two-dimensional contours related to the velocity, pressure, temperature, streamlines, and velocity vectors inside the computational domain are obtained.

The temperature contour shows the temperature of the heated wall and how the temperature is changed inside the wind tower.

Furthermore, by viewing the contours related to velocity, streamlines, and velocity vectors, one can easily understand that the airflow enters the top levels with more momentum and velocity due to the less hydraulic resistance between the top and bottom levels.

Nevertheless, as seen in the velocity vector contour, the forced airflow entering the bottom levels will cause a rotating airflow inside such levels.

Finally, the air will rise to exit through the pressure outlet boundary on the top right side of the wind tower as it collides with the diagonal hot wall due to the natural convection phenomenon.