An experimental and numerical investigation into the heat transfer of naturally convecting fin arrays within enclosures

Computational fluid dynamics is used to predict the fluid flow around three geometrically similar naturally convecting fin arrays, suspended in turn within an enclosure. The numerical predictions of the velocity and temperature profiles, at the upper and lower opening of a fin passage, are then compared to previously obtained measurements. The non-dimensional profiles for both the numerical and experimental results compare well for the three fins, although there are some discrepancies between the predicted and measured dimensioned velocities. The profiles are discussed with a view to determining the effect of approximated boundary conditions on the accuracy of computational predictions of natural convection within an enclosure. Smoke flow visualization is used to illustrate the salient features of the air flow within the enclosure and to give a qualitative comparison with the numerical predictions. The combination of measurements, predictions and smoke visualisation affords considerable insight into the interaction between the fin array and enclosure. A comparison between the predicted and measured relationship between the Nusselt and modified Rayleigh number is made.