On the linearity, turndown ratio and shape of the bluff body for vortex flowmeter

Flow past bluff bodies is abundantly studied in the literature. However, confinement effect imposed by a circular pipe on the shedding characteristics of bluff bodies is rarely addressed. Application of such configuration can be seen in vortex flowmeters, heat transfer enhancement devices, energy harvesting devices etc. The present study highlights the influence of circular pipe on the shedding characteristics of two dimensional bluff bodies. The discussion is focused towards the design issues pertinent to vortex flowmeter. Nonlinearity in St-Re-D relation is due to transition from laminar to turbulent flow. Cross correlation technique and contraction cone design can be employed in transition regime to extend lower operating range. Further, there is a need to explore bluff body shapes which can be used for flow measurement in laminar, transition and turbulent flow regimes. The fundamental discussion reported in this study will impart new insights towards improving the performance of these devices further. (C) 2019 Elsevier Ltd. All rights reserved.