Experimental Investigation on Flow Downstream of a Square Bluff Body at Different Angles

علوم کاربردی و محاسباتی در مکانیک

Article 11, Volume 31, Issue 2 - Serial Number 22, 2020, Pages 177-187   

Document Type: مقاله کوتاه

DOI: 10.22067/fum-mech.v31i2.81306

Authors

Ehsan Ardekani¹; AliReza Teymourtash¹; Mohammad Ali Ardekani^{* 2}

¹Department of Mechanical Engineering , ferdowsi university of Mashhad

²Iranian Research Organization for Science and Technology

Abstract

Study of vortex shedding and flow downstream of a square bluff body can be used to a vortex flowmeter. In this paper, flow velocity, turbulence intensity and vortex shedding from a 15 mm square bluff body have been investigated experimentally using hot-wire anemometer. Results show that flow angle has little effect on flow velocity distribution and turbulence intensity. However, variations of Strouhal  number (St) with respect to the flow angle is large, so that Strouhal number at flow angle of 12° has the maximum value of 0.176 and at angle of 43°, it has the minimum value of 0.129. If the probe is placed in the region x/a=2.5 and 2.2≤y/a≤6, the velocity will be equal to the free stream velocity and the vortices will be measureable.

Keywords

Vortex shedding; square bluff body; Hot-wire anemometer; Vortex flowmeter

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