Finned Tube Heat Exchanger CFD Simulation, ANSYS Fluent Training

Description

In this project, the heat transfer inside a Finned Tube heat exchanger is investigated by ANSYS Fluent software.

The geometry of this project is designed in the ANSYS design modeler and meshed in ANSYS meshing software. The mesh type used for this geometry is hybrid (structured in the upstream and downstream and unstructured in the main part). The element number is 890710.

It should be mentioned that this geometry only consists of a heat exchanger segment. Since a heat exchanger usually has symmetry, this feature has been used, and instead of solving the flow in the whole heat exchanger, this analysis has been done only in a part of the heat exchanger.

finned tube heat exchanger Methodology

Finned Tube heat exchangers are finned tubes whose main purpose is to create a wider surface about 20 to 30 times larger than the surface of a normal tube heat exchanger. As a result, the volume of the heat exchanger, as well as the economic and process efficiency, are greatly increased.

The energy equation is activated to obtain temperature distribution inside the computational domain.

Since in this analysis, the movement of fluid on the surfaces of the heat exchanger is very important, the SST k-omega model is exploited to solve turbulent flow equations, and the ideal gas model has been used to determine the density changes in proportion to temperature.

The fluid flow enters the domain with a velocity of 1.42 m/s and a temperature of 338K. This hot flow then collides with the two cold tubes with a temperature of 303K placed in the middle of the domain and loses their temperature.

finned tube heat exchanger Conclusion

Finally, the contours related to pressure, velocity, temperature, streamlines, and velocity vectors are obtained. As seen in the temperature contour, the fluid flow’s temperature drops near the cold tubes due to the convective heat transfer.

Also, another important point that should be considered is the disadvantages of wake regions that occur between and after the cold tubes, which hampers the heat transfer between the flow and the cold tubes.