నైరూప్య

Flow Visualization around Perforated Circular Finned Tubes by CFD

Yogesh Pal, Naushad Ahmad Ansari, M. Zunaid

Rate of heat transfer increases by several folds with the increase in the surface area of heat exchangers, in practice this is often achieved by having fins at the surface of heat exchangers. The objective of the present study was to visualize the air flow around perforated circular finned tube (PCFT) through computational fluid dynamics (CFD). The air-side flow was visualized through simulation in fluent. Visualization of flow of air around the tube and fin for various cases were studied. These cases include the different positions of perforations on fins with respect to stagnation point. The different positions selected for perforations with respect to stagnation point are no holes and holes at an angle of 90 degree, 100 degree, 110 degree, 115 degree, 120 degree, 140 degree, 145 degree, 150 degree, 160 degree, and 170 degree. Gambit was used for construction of geometry and k-epsilon model was used for flow visualization. The perforation at an angle of 120 degree with respect to stagnation point was found to be the best location because recirculation of flow at this location found to be least. However perforations at the angles greater than 90 degree but less than 170 degree were effective in reducing the recirculation