Numerical simulation of cushioning problem for blunt bodies using boundary element method

• Autorzy: Barjasteh M. , Zeraatgar H.
• Języki publikacji: EN

Abstrakty

EN

Induced air pressure and resulting free surface profile due to air cushioning layer is studied. The study is mainly focused on 2D blunt circular bodies with constant downward speed. The problem is first solved for the air flow between the body and the free surface of the water. Then the results are employed to solve the problem for the water problem, numerically. Both air and water problem are assumed to be governed by Laplace potential equation. Depending on the induced pressure and velocity of the escaping air flow from cushioning layer, compressibility of the air is also included in the modeling. Gravitational acceleration is also included in the model. An iterative boundary element method is used for numerical solution of both air and water problems. Instantaneous pressure distribution and free surface profile are evaluated for different bodies. The results of calculation for large blunt bodies show that inviscid potential method can fairly approximate the problem for large blunt bodies. Additionally, the behavior of the air pressure for the very blunt body is impulsive and the magnitude of the peak pressure is in order of impact pressure of water entry. The obtained results are compared with analytical method. The comparison shows that as the bluntness of a body increases, the better agreement is concluded

• Wydawca: -
• Czasopismo: Polish Maritime Research
• Rocznik: 2018
• Tom: 25
• Numer: Special Issue S1
• Opis fizyczny: p.85-93,fig.,,ref.

Twórcy

autor

Barjasteh M.

• Amirkabir Laboratory of Hydrodynamics (ALH), Faculty of Maritime Engineering, Amirkabir University of Technology, Tehran, Iran

autor

Zeraatgar H.

• Amirkabir Laboratory of Hydrodynamics (ALH), Faculty of Maritime Engineering, Amirkabir University of Technology, Tehran, Iran

Bibliografia

• 1. J.H.G., Verhagen, 1967,“The impact of a flat plate on a water surface.”, J. Ship research 11, 211-233.
• 2. O. Reynolds, 1886, “On the theory of lubrication and its application to Mr. Beauchamp tower’s experiments, including an experimental determination of viscosity of olive oil.” Philos. Trans. R. Soc. London Ser. A 177, 157-234.
• 3. N.G., Asryan, 1972, “Solid plate impact on surface of incompressible fluid in the presence of a gas layer between them.”, SSR Mek25, 32{49.
• 4. S.K., Wilson, 1991, “A mathematical model for the initial stages of fluid impact in the presence of a cushioning fluid layer.”, J. Engineering mathematics 25, 265-285.
• 5. P. Hicks and R. Purvis, 2010, “Air cushioning and bubble entrapment in three-dimensional droplet impacts.” J. Fluid Mechanics 649, 135-163.
• 6. P. Hicks and R. Purvis, 2011, “Air cushioning in droplet impacts with liquid layers and other droplets.” Physics of fluids 23.
• 7. P.D. Hicks and R. Purvis, 2013, “Liquid solid impacts with compressible gas cushioning.” Journal of Fluid Mechanics 735, 120-149.
• 8. P.D. Hicks, E.V. Ermanyuk, N.V. Gavrilov, and R. Purvis, 2012 , “A ir t rapping at impact of a rig id sphere onto a liquid.” J. Fluid Mechanics 695, 310-320.
• 9. S. Mandre and M.P. Brenner, 2012, “The mechanism of a splash on a dry solid surface.” Journal of Fluid Mechanics 690, 148-172.
• 10. F.T. Smith, L.Li and G.X. Wu, 2003,“Air cushioning with a lubrication/inviscid balance.” Journal of Fluid Mechanics 482, 291-318
• 11. J.O. Marston, I.U. Vakarelski, and S.T. Thoroddsen, 2011, “Bubble entrapment during sphere impact onto quiescent liquid surfaces.” J. Fluid Mechanics 680, 660-670
• 12. T. Tran, H. de Maleprade, C . Sun, and D. Lohse, 2013, “A ir entrainment during impact of droplets on liquid surfaces.” J. Fluid Mechanics 726.
• 13. G.R.G. Lewison, and W.M. Maclean, 1968, “On the cushioning of water impact by entrapped air.” J. Ship research 12, 116-130
• 14. S.T. Thoroddsen, T.G. Etoh, K. Takehara, N. Ootsuka and Y. Hatsuki, 2005 “The air bubble entrapped under a drop impacting on a solid surface.” J. Fluid Mechanics 545, 203-212.
• 15. W. Bouwhuis, M.H.W. Hendrix, M.H.W., D. van der Meer, and J.H. Snoeijer, 2015, “Initial surface deformations during impact on a liquid pool.” J. Fluid Mechanics 771, 503-519.
• 16. J.T. Katsikadelis, “BOUNDARY ELEMENTS: Theory and Applications”, Elsevier, 2002

Identyfikatory

DOI

10.2478/pomr-2018-0028