Description

In this project, we present the CFD simulation of the Ground Heat Exchanger using ANSYS Fluent software.

The ground heat exchangers (GHEs) consist of pipes buried underground. The working fluid flows inside these buried pipes underground and undergoes heat transfer with the ground.

Note that the temperature of the ground is slightly different from the temperature of the environment above it.

For example, in the winter season, the ground temperature is higher than the very cold temperature of the ambient air. Therefore, the fluid flowing inside the pipes is heated by receiving the ground heat; therefore, the heat exchanger system takes on a heating operation.

However, in the summer season, the ground temperature is lower than the very warm temperature of the ambient air. Therefore, the fluid flowing inside the pipes is cooled by releasing heat into the cold ground; therefore, the heat exchanger system takes on a cooling operation.

Therefore, we implemented the present simulation project in two different cases: once, as a heating mechanism in the cold season, and once, as a cooling mechanism in the warm season.

Methodology

First, we modeled the geometry in Design Modeler software. Then, we meshed the model using ANSYS Meshing software, and 3060397 elements were generated. Finally, we simulated the electroplating process in ANSYS Fluent software.

In this simulation, we set the boundary conditions to improve the heat transfer. We assumed a fixed temperature for the ground in both cases. Also, we accounted for convection heat transfer between the walls and the air surrounding environment.

In addition, we set a pressure jump condition for the pump at the intake of the pipes to help circulate the flow throughout the system.

Conclusion

We obtained contours of temperature distribution in 2D and 3D for both heating and cooling cases. The results show that the present ventilation system heats the air in the winter season and cools the air in the summer season.

In addition, we obtained the contour of the pressure distribution inside the pipes and the streamlines for ambient air.