PERFORMANCE OPTIMIZATION OF FINNED SURFACES BASED ON THE EXPERIMENTAL AND NUMERICAL STUDY

This paper presents the findings of numerical and experimental investigations into the forced convection heat transfer from horizontal surfaces with straight rectangular fins at Reynolds numbers ranging from 23600 to 150000. A test set-up was constructed to measure the heat transfer rate from a horizontal surface with a constant number of fins, fin width and fin length under different flow conditions. Two-dimensional numerical analyses were performed to observe the heat transfer and flow behaviour using a computer program developed based on the OpenFOAM platform. The code developed was verified by comparing the numerical results with the experimental results. The effect of geometrical parameters on heat transfer coefficient and Nusselt number were investigated for different fin height and width ratios. Numerical results show that one way to increase heat transfer by modifying the fin structure geometrical parameters. With the help of the obtained results, a correlation for Nusselt number was developed and presented for steady-state, turbulent flows over rectangular fin arrays for Reynolds number ranging from 23600 to 150000, Prandtl number ranging from 0.705 to 5.41, for fin height ratios h/H ranging from 0.166 to 0.333, and fin thickness to fin height ratios (t/h) between of 0.066 and 0.20. The correlation developed predicts the Nusselt number with a relative RMS error of 0.36%.