Citation:
Ronald W. Yeung,Lu Wang.Radiation and Exciting Forces of Axisymmetric Structures with a Moonpool in Waves[J].Journal of Marine Science and Application,2018,(3):297-311.[doi:10.1007/s11804-018-0043-3]
Click and Copy
Radiation and Exciting Forces of Axisymmetric Structures with a Moonpool in Waves
Ronald W. Yeung,Lu Wang.Radiation and Exciting Forces of Axisymmetric Structures with a Moonpool in Waves[J].Journal of Marine Science and Application,2018,(3):297-311.[doi:10.1007/s11804-018-0043-3]
Info
- Title:
- Radiation and Exciting Forces of Axisymmetric Structures with a Moonpool in Waves
- Author(s):
- Ronald W. Yeung; Lu Wang
- Affilations:
- Keywords:
- Moonpool; Spar; Oscillating water column; Potential flow; Hybrid method; Axisymmetric body
- DOI:
- 10.1007/s11804-018-0043-3
- Abstract:
- A highly efficient "hybrid integral-equation method" for computing hydrodynamic added-mass, wave-damping, and waveexciting force of general body geometries with a vertical axis of symmetry is presented. The hybrid method utilizes a numerical inner domain and a semi-infinite analytical outer domain separated by a vertical cylindrical matching boundary. Eigenfunction representation of velocity potential is used in the outer domain; the three-dimensional potential in the inner domain is solved using a "two-dimensional" boundary element method with ring sources and ring dipoles to exploit the body symmetry for efficiency. With proper solution matching at the common boundary, both radiation and diffraction potentials can be solved efficiently while satisfying the far-field radiation condition exactly. This method is applied to compute the hydrodynamic properties of two different body geometries:a vertical-walled moonpool with a bottom plate that restricts the opening and a spar-like structure with a diverging bottom opening inspired by designs of floating Oscillating Water Columns. The effects of the size of the bottom opening on the hydrodynamic properties of the body are investigated for both geometries. The heave motion of the floater as well as the motion of the internal free surface under incident wave excitation are computed and studied for the spar-like structure.
References:
Bachynski EE, Young YL, Yeung RW (2012) Analysis and optimization of a tethered wave energy converter in irregular waves. Renew Energy 48:133-145. https://doi.org/10.1016/j.renene.2012.04.044
Chau FP, Yeung RW (2012) Inertia, damping, and wave excitation of heaving coaxial cylinders. In:Proceedings of the ASME 31st international conference on ocean, offshore and arctic engineering. Rio de Janeiro, Brazil, pp 803-813. https://doi.org/10.1115/OMAE2012-83987
Fãlcao AFO, Henriques JCC, Cândido JJ (2012) Dynamics and ôptimization of the OWC spar buoy wave energy converter.Renew Energy 48:369-381. https://doi.org/10.1016/j.renene.2012.05.009
Faltinsen OM, Rognebakke OF, Timokha AN (2007) Two-dimensional resonant piston-like sloshing in a moonpool. J Fluid Mech 575:359-397. https://doi.org/10.1017/S002211200600440X
Faltinsen OM, Timokha AN (2015) On damping of two-dimensional piston-mode sloshing in a rectangular moonpool under forced heave motions. J Fluid Mech 772:R1. https://doi.org/10.1017/jfm.2015.234
Fredriksen AG, Kristiansen T, Faltinsen OM (2014) Wave-induced response of a floating two-dimensional body with a moonpool.Phil Trans R Soc A 373:20140109. https://doi.org/10.1098/rsta.2014.0109
Hamilton JA, Yeung RW (2003) Spectral shell and perfectly transparent open-boundary condition for unsteady wave-body interactions.J Offshore Mech Arct Eng 125(1):9-16. https://doi.org/10.1115/1.1537721
Haskind MD (1957) The exciting forces and wetting of ships in waves.Izv Akad Nauk SSSR, Otd Tekh Nauk 7:65-79
Kristiansen T, Faltinsen OM (2012) Gap resonance analyzed by a new domain-decompositionmethod combining potential and viscous flow. Appl Ocean Res 34:198-208. https://doi.org/10.1016/j.apor.2011.07.001
Kristiansen T, Sauder T, Firoozkoohi R (2013) Validation of a hybrid code combining potential and viscous flow with application to 3D moonpool. In:Proceedings of the ASME 2013 32nd international conference on ocean, offshore and arctic engineering. Nantes, France, V009T12A029. https://doi.org/10.1115/OMAE2013-10748
Lee M-Y (1985) Unsteady fluid-structure interaction in water of finite depth. PhD thesis, University of California, Berkeley Matsui T, Kato K (1991) The analysis of waveinduced dynamics of ocean platforms by hybrid integral equation method. Int J Offshore Polar Eng 1(2):146-153
Matsui T, Kato K, Shirai T (1987) A hybrid integral equation method for diffraction and radiation of water waves by three-dimensional bodies. Comput Mech 2(2):119-135
Mavrakos SA (1988) Hydrodynamic coefficients for a thick-walled bottomless cylindrical body floating in water of finite depth. Ocean Eng 15(3):213-229. https://doi.org/10.1016/0029-8018(88)90040-6
Mavrakos SA (2004) Hydrodynamic coefficients in heave of two concentric surface-piercing truncated circular cylinders. Appl Ocean Res 26:84-97. https://doi.org/10.1016/j.apor.2005.03.002
McIver P (2005) Complex resonances in the water-wave problem for a floating structure. J Fluid Mech 536:423-443. https://doi.org/10.1017/S0022112005005021
McIver P, McIver M (2007) Motion trapping structures in the threedimensional water-wave problem. J Eng Math 58(1-4):67-75.https://doi.org/10.1007/s10665-006-9103-9
Molin B (2001) On the piston and sloshing modes in moonpools.J Fluid Mech 430:27-50. https://doi.org/10.1017/S0022112000002871
Molin B, Zhang X, Huang H, Remy F (2018) On natural modes in moonpools and gaps in finite depth. J Fluid Mech 840:530-554.https://doi.org/10.1017/jfm.2018.69
Newman JN (1999) Radiation and diffraction analysis of the McIver toroid. J Eng Math 35(1):135-147. https://doi.org/10.1023/A:1004391615875
Shipway BJ, Evans DV (2003) Wave trapping by axisymmetric concentric cylinders. J Offshore Mech Arctic Eng 125:59-64.https://doi.org/10.1115/1.1537727
Wang L, Son D, Yeung RW (2016) Effect of mooring-line stiffness on the performance of a dual coaxial-cylinder wave-energy converter. Appl Ocean Res 59:577-588. https://doi.org/10.1016/j.apor.2016.07.014
Wehausen JV (1971) The motion of floating bodies. Ann Rev Fluid Mech 3(1):237-268. https://doi.org/10.1146/annurev.fl.03.010171.001321
Wehausen JV, Webster WC, Yeung RW (2016) Hydrodynamics of ships and ocean systems, lecture notes for course ME241.University of California, Berkeley. Revised
Yeung RW (1975) A hybrid integral-equation method for timeharmonic free-surface flow. In:Proceedings of the first international conference on numerical ship hydrodynamics. Gaithersburg, Maryland, USA, pp 581-607
Yeung RW (1981) Added mass and damping of a vertical cylinder in finite-depth waters. Appl Ocean Res 3(3):119-133.https://doi.org/10.1016/0141-1187(81)90101-2
Yeung RW (1985) A comparative evaluation of numerical methods in free-surface flows. In:Hydrodynamics of ocean-wave utilization, IUTAM symposium, Lisbon, Portugal. Springer-Verlag, Berlin, pp 325-356
Yeung RW, Bouger YC (1979) A hybrid integralequation method for steady two-dimensional ship waves. Int J Numer Meth Eng 14(3):317-336. https://doi.org/10.1002/nme.1620140303
Yeung RW, Seah RKM (2007) On Helmholtz and higher-order resonance of twin floating bodies. J Eng Math 58(1-4):251-265.https://doi.org/10.1007/s10665-006-9109-3
Yuen MMF, Chau FP (1987) A hybrid integral equation method for wave forces on three-dimensional offshore structures. J Offshore Mech Arct Eng 109(3):229-236. https://doi.org/10.1115/1.3257014
Zhang X, Bandyk P (2013) On two-dimensional moonpool resonance for twin bodies in a two-layer fluid. Appl Ocean Res 40:1-13.https://doi.org/10.1016/j.apor.2012.11.004
Zhang X, Bandyk P (2014) Two-dimensional moonpool resonance for interface and surface-piercing twin bodies in a two-layer fluid.Appl Ocean Res 47:204-218. https://doi.org/10.1016/j.apor.2014.05.005
Memo
- Memo:
-
Received date:2018-6-3;Accepted date:2018-7-22。
Corresponding author:Ronald W. Yeung,rwyeung@berkeley.edu
