Finned Tube Heat Exchanger CFD Simulation

Finned Tube Heat Exchanger: Thermal-Fluid Analysis Using ANSYS Fluent

This project presents a detailed CFD investigation of heat transfer mechanisms within a Finned Tube heat exchanger using ANSYS Fluent. The analysis focuses on a representative segment of the exchanger, leveraging symmetry to reduce computational requirements while maintaining solution accuracy.

The computational domain was developed in ANSYS Design Modeler and discretized using a hybrid meshing approach—structured elements in upstream/downstream regions and unstructured elements in the complex interaction zone—totaling 890,710 elements for high-resolution flow capture.

The simulation leverages the SST k-omega turbulence model to accurately resolve near-wall fluid behavior, which is critical for heat transfer prediction. Temperature-dependent density variations are accounted for using the ideal gas model. The thermal interaction occurs between hot air entering at 338K (1.42 m/s) and two cold tubes maintained at 303K.

Results provide comprehensive visualization of pressure distributions, velocity fields, temperature gradients, and flow patterns through streamlines and vector plots. The analysis clearly demonstrates temperature reduction in the fluid as it passes the cold tubes due to convective heat transfer. A significant finding highlights the formation of wake regions between and downstream of the tubes, which negatively impacts thermal exchange efficiency by reducing effective contact between the fluid and heat transfer surfaces.

This simulation illustrates how finned tube designs can achieve 20-30 times greater surface area than conventional tube exchangers, substantially improving volumetric efficiency and economic performance.