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

Document Type : مقاله کوتاه

Authors

• Ehsan Ardekani ¹
• AliReza Teymourtash ¹
• Mohammad Ali Ardekani ²

¹ Department of Mechanical Engineering , ferdowsi university of Mashhad

² Iranian Research Organization for Science and Technology

10.22067/fum-mech.v31i2.81306

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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