Role of Shape Factor in Wake Width Development at Moderate Reynolds Number
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Abstract
This paper addresses the wake width variability downstream of bluff bodies with variable shape factors. The numerical investigation is conducted at the laminar vortex shedding regime with moderate Reynolds numbers (Re) ranging from 80 to 160. Shape factor (S.F.) is decided by the extent of the bluffness imparted to the rear part of the body, 0.5 being the bluffest, while 2.0 is the streamlined. The results point out that Re had a consistent impact on wake width for all body shapes, while the same couldn’t be stated for the shape factor. The shape factor had a non-intrusive effect on wake behaviour, and all shape factor configurations produced wakes of an identical structure at a particular Reynolds number. Quantitative comparisons also indicate that wake width stays on the same scale as projected body length. It seems that the Reynolds number plays a more significant role than shape in establishing wake structure for the laminar regime. The findings of this paper provide relevant information for passive flow control and bluff body design with small geometric variations in moderate Reynolds number regimes.
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This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
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