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http://dx.doi.org/10.5762/KAIS.2014.15.6.3950

Numerical Study of Drag Forces Acting on a Submerged Square Cylinder in Steady Flow Condition  

Lee, Du Han (River and Coastal Research Division, Korea Institute of Construction Technology)
Kim, Young Joo (River and Coastal Research Division, Korea Institute of Construction Technology)
Rhee, Dong Sop (River and Coastal Research Division, Korea Institute of Construction Technology)
Publication Information
Journal of the Korea Academia-Industrial cooperation Society / v.15, no.6, 2014 , pp. 3950-3960 More about this Journal
Abstract
In this study, the drag forces on a submerged square cylinder were analyzed using a three dimensional hydrodynamic model. The numerical results were compared with the experimental results to check the reliability of the numerical simulations, and the characteristics of the drag forces with the relative depths were analyzed by analyzing the pressure acting on the cylinder surface, which are normally difficult to measure experimentally. The numerical results showed that the drag forces acting on a submerged square cylinder originate mainly from the pressure forces, and component of the shear forces decreased with increasing relative depth. The pressure coefficient distributions showed that in the case of a low relative depth, a relatively high pressure was formed in the front of a cylinder, and a relatively low pressure was formed in the rear, which gives a high drag coefficient. In a high relative depth, the pressure in the front decreased and pressure in the rear increased, which is a similar phenomenon to that normally observed in two dimensional square cylinder flow. The effect of the static pressure was analyzed and the surface elevation difference between the front and rear zone of a cylinder has a limited effect on the drag forces. Finally, the numerical results showed that the drag forces acting on a submerged square are dominated by the dynamic pressure formed by three dimensional flow and the distribution of local surface elevation.
Keywords
Drag coefficient; Dynamic pressure; Pressure coefficient; Submerged square cylinder; Three dimensional hydro dynamic model;
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