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Periodic fluid flow, heat transfer, friction loss and thermal performance characteristics in square channels with V-ribs with tail-end cut were numerically investigated. The V-ribs were installed on a plate which was diagonally placed in a channel. The objective of the present work is to study the effects of the angle of tail-end cut of ribs (β = 0o, 20o, 30o, 45o and 60) on heat transfer enhancement. The study was carried out under constant heat flux condition for Reynolds numbers (Re) from 3000 to 20,000. The pitch ratio (PR= p/H) and blockage ratio (BR=b/H) of ribs were fixed at 1.0 and 0.15, respectively. As compared to the channel without rib, the one with ribs possessed considerably higher heat transfer and friction loss. At similar conditions, the ribs with larger angle of cut (β) gave lower heat transfer (Nusselt number, Nu) and friction loss (friction factor, f) due to the weaker turbulence and lower resistance to the flow. Among the ribs considered the ones with β of 0 (the ribs without cut) offered the maximum thermal enhancement factor (overall energy performance) of 1.65 at Reynolds number of 3000.
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Faculty of Engineering and Technology
Mahanakorn University of Technology
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