Vortex shedding from slender surface mounted pyramids
نویسندگان
چکیده
The current investigation examines periodic vortex shedding from surface mounted pyramids with taper ratios (2*height/base diameter) of 7.6 to 14.3 in a thin boundary layer using surface pressure measurements along the obstacle faces. Over the lower portion of the pyramids (y/h<~0.5) regular periodic vortex shedding was observed. Near the tip, a large time-scale structure was observed. This structure exhibits a strongly modulated period. In general, the period decreases with increasing taper ratio. The results are found to be similar to tapered plates of similar taper ratios and pyramids with smaller taper ratios. The discrepancy between taper plates and pyramids with taper ratios less than 7.6 are attributed to the inclined leading edge and the afterbody effect of the pyramids.
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