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http://dx.doi.org/10.5407/jksv.2021.19.2.015

Numerical study of a freely falling rigid sphere on water surface  

Ku, BonHeon (School of Mechanical Engineering, Pusan National University)
Pandey, Deepak Kumar (School of Mechanical Engineering, Pusan National University)
Lim, Hee-Chang (School of Mechanical Engineering, Pusan National University)
Publication Information
Journal of the Korean Society of Visualization / v.19, no.2, 2021 , pp. 15-25 More about this Journal
Abstract
Numerical studies on the hydrodynamics of a freely falling rigid sphere in bounded and unbounded water domains are presented having investigation on the drag coefficient, normalized velocity, surface pressure and skin friction coefficient as a function of time. Two different conditions of the bounded and unbounded domains have been simulated by setting the blockage ratio. Four cases of bounded domains (B.R. = 1%, 25%, 45%, 55%, 65% and 75%) have been taken, whereas the unbounded domain has been considered with 0.01%. In the case of the bounded domain (higher values of B.R.), a substantial reduction in normalized velocity and increase in the drag coefficient have been found in presence of the bounded domain. Moreover, bounded domains also yield a significant increase in the pressure coefficient when the sphere is partially submerged, but the insignificant effect is found on the skin friction coefficient. In the case of the unbounded domain, a significant reduction in normalized velocity occurs with a decrease in Reynolds number (Re) and also increase in the drag coefficient.
Keywords
Free falling body; Bounded domain; Unbounded domain; Volume of Fluid; Blockage ratio;
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  • Reference
1 T. von Karman, "The impact on seaplane floats during landing," Technical note no. 321, National Advisory Committee for Aeronautics, Washington DC, United States, 1929.
2 H. Wagner, "Phenomena associated with impacts and sliding on liquid surfaces," Zeitschr. Angew. Math. Mech., vol. 12, pp. 193-215, 1932.   DOI
3 A. May, "Vertical entry of missiles into water," J. Appl. Phys., vol. 23, pp. 1362-1372, 1952.   DOI
4 S. L. Chuang, "Slamming tests of threedimensional models in calm water and waves," Naval Ship Research and Development Center, Maryland, Accession no. AD0767021, 1973.
5 M. Greenhow, "Wedge entry into initially calm water," Appl. Ocean Res., vol. 9, pp. 214-223, 1987.   DOI
6 A. A. Korobkin and V. V. Pukhnachov, "Initial stage of water impact," Annu. Rev. Fluid Mech., vol. 20, pp. 159-185, 1988.   DOI
7 R. Zhao and O. Faltinsen, "Water entry of two-dimensional bodies," J. Fluid Mech., vol. 246, pp. 593-612, 1993.   DOI
8 P. Tyvand and T. Miloh, "Free-surface flow generated by a small submerged circular cylinder starting from rest," J. Fluid Mech., vol. 286, pp. 103-116, 1995.   DOI
9 X. Zhu, O. M. Faltinsen, and C. Hu, "Water entry and exit of a horizontal circular cylinder," ASME J. Offshore Mech. Arct. Eng., vol. 129, pp. 253- 264, 2007.   DOI
10 A. C. Fairlie-Clarke and T. Tveitnes, "Momentum and gravity effects during the constant velocity water entry of wedge-shaped sections," Ocean Eng., vol. 35, pp. 706-716, 2008.   DOI
11 C. R. Nisewanger, "Experimental determination of pressure distribution on a sphere during water entry," Naval Ordnance Test Station: China Lake, CA, USA, 1961.
12 J. L. Baldwin, "Vertical water entry of cones," Naval Ordnance Laboratory, White Oak, Silver Spring, Maryland, Accession no. AD0723821, 1971.
13 S. Abrate, "Hull slamming," Appl. Mech. Rev., vol. 64, 060803, 2011.   DOI
14 A. Shams, M. Jalalisendi, and M. Porfiri, "Experiments on the water entry of asymmetric wedges using particle image velocimetry," Phys. Fluids, vol. 27, pp. 027103 1-26, 2015.   DOI
15 A. El Malki Alaoui, A. Neme, A. Tassin, and N. Jacques, "Experimental study of coefficients during vertical water entry of axisymmetric rigid shapes at constant speeds," Appl. Ocean Res., vol. 37, pp. 183-197, 2012.   DOI
16 De Backer, M.Vantorre, C. Beels, J. De Pre, S. Victor, J. De Rouck, C. Blommaert and W. Van Paepegem, "Experimental investigation of water impact on axisymmetric bodies," Appl. Ocean Res., vol. 31 (3), pp. 143-156, 2009.   DOI
17 S.-L. Chuang and D. T. Milne, "Drop tests of cones to investigate the three-dimensional effects of slamming," Naval Ship Research and Development Center, Washington DC., Accession no. AD0881183, 1971.
18 Peseux, L. Gornet and B. Donguy, "Hydrodynamic impact: numerical and experimental investigations," J. Fluids Struct., vol. 21, pp. 277-303, 2005.   DOI
19 K. M. T. Kleefsman, G. Fekken, A. E. P. Veldman, B. Iwanowski, and B. Buchner, "A volume-of-fluid based simulation method for wave impact problems," J. Comput. Phys., vol. 206, pp. 363-393, 2005.   DOI