Investigation of Variation in Galloping Region on Harnessed Power for Two Tandem

Atashi, Vida; GHomeshi, Mehdi

doi:10.22113/jmst.2017.50239

Investigation of Variation in Galloping Region on Harnessed Power for Two Tandem

Document Type : Original Manuscript

Authors

Vida Atashi

Mehdi GHomeshi

Water Sciences Engineering Faculty, Shahid Chamran University, Ahvaz, Iran.

10.22113/jmst.2017.50239

Abstract

In this paper, the effect of in phase or out of phase fluctuation of two tandem circular cylinders with PTC on FIM is investigated. Flow-Induced Motion (FIM) is a phenomenon that frequently occurs when slender structures are subjected to a transverse fluid flow.VIV and galloping are the most common phenomena in FIM which occurs due to interaction between shear layers and wakes of upstream cylinders. In this paper, the effect of tandem spacing on FIM of two circular cylinders with PTC is investigated by visualization. The power harness graphs for upstream, downstream and synergy was extracted with VIVACE. The VIVACE consists of a rigid bluff body that is mounted on an elastic base and exposed to fluid flow. The mechanical energy from the cylinder vibration is also transmitted by a PTO to a generator. Normally, the harness power in galloping region increases with increasing in flow velocity and Reynolds number. Unlike what was expected, drops and jumps in Power harness in the velocity range of 0.9

Keywords

Harnessed Power

Galloping

Out of phase

in phase

20.1001.1.20088965.1397.17.4.4.9

Subjects

مهندسی دریا

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