Author : Sanal M V 1
Date of Publication :13th July 2017
Abstract: The flow phenomena around bluff bodies or non-streamlined bodies in fluids are always of some engineering importance. Most of the engineering structures like buildings, bridges etc. can be considered as bluff bodies as far as the air or water flow in which the structure is being situated, is considered. This paper aims at the study of vortex induced vibration and suppression of the VIV on some common models of structures which can be considered, of having some engineering importance. The main parameter associated with the VIV formation is the Strouhal number (St.) which is the non-dimensional frequency of vortex shedding. The VIV was captured by using Fieldpaq Dynamic Signal Analyzer which has frequency ranges from 0 Hz to 40 kHz. The cylinders with varying number of fins and splitter plate length are tested. The methods to control VIV can be classified into three as active, passive or compound method. The passive method, would give some structural modifications on the model and considered to reduce the VIV formation. On the other hand,. Among these, the active and compound methods are costlier compared to the passive method. Therefore on an economic point of view the engineers are keen to develop more and more methods to suppress the VIV effectively with a lesser cost i.e., by employing the passive method. My study is on employing the model with straight fins.
Reference :
-
- Bearman, P. W., Brankovic, M., 2006. Measurements of transverse forces on circular cylinders undergoing vortex-induced vibration. Journal of Fluids and Structures22, 829-836.
- S.Ozono, 1999, Flow control of vortex shedding by a short splitter plate asymmetrically arranged downstream of a cylinder, Phys. Fluids 11, 2928
- Durao, D.G, Heitor, M.V, Pereira, J.F 1988: ‘Measurement of turbulent and periodic flows around a square cylinder’, Experiments in Fluids, Vol.6, p. 298-304.
- Lee KeeQuen (2014), “Investigation on the effectiveness of helical strakes in suppressing VIV of flexible riser’’. Applied Ocean Research 44, 82–91
- Zachary J. Taylor, Gregory A. Kopp, 2014 Effects of leading edge geometry on the vortex shedding frequency of an elongated bluff body at high Reynolds numbers, J. Wind Eng. Ind. Aerodyn. 128 66–75
- K. Kwon, H. Choi. 1996 ‘Control of laminar vortex shedding behind a circular cylinder using splitter plates’. Phys. Fluids 8 479-486
- Korkischko I, Meneghini JR. 2010 ‘Experimental investigation of flow-induced vibration on isolated and tandem circular cylinders fitted with strakes’. Journal of Fluids and Structures;26:611–25.