Journal of Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회논문집)

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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Numerical Simulations of Rip Currents Under Phase-Resolved Directional Random Wave Conditions

위상을 포함한 다방향 불규칙파 조건에서의 이안류 수치모의

  • Choi, Junwoo (Coastal Research Laboratory, Korea Inst. of Civil Eng. & Building Tech.)
  • 최준우 (한국건설기술연구원 해안연구실험실)
  • Received : 2015.07.14
  • Accepted : 2015.08.21
  • Published : 2015.08.31
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Abstract

Recently, Choi et al.(2015) showed that a numerical simulation of the SandyDuck experiment under a directional random wave environment agreed well with the experimental data including the wave height distribution of the random waves, the well-developed longshore current and its energetic fluctuation. Based on the Boussinesq modeling, this study investigates the effect of the alongshore variations, which are induced by not only the field topography but also the phase interaction of multidirectional random waves in the surf zone wave field, on the rip currents. As a result, transient rip currents as well as topographical rip currents cause the complicated surfzone circulation and mixing process due to their interactions in a multi-directional random wave condition while the topographical rip currents are dominant in a monochromatic wave condition.

Choi et al.(2015)은 최근 Boussinesq 방정식 모형인 FUNWAVE를 이용하여, 다방향 불규칙파 조건으로 SandyDuck 현장실험 조건의 연안흐름을 수치모의하여, 연안류 유속분포 뿐만 아니라 전단파동 등의 계산결과가 관측결과와 잘 일치함을 보였다. 이 연구모형을 기반으로 SandyDuck 지형과 더불어 다방향 위상의 상호작용에 의해 발생되는 연안방향의 파에너지 비균등성이 이안류 발달에 미치는 영향을 고찰하기 위해 수치모의를 수행하였다. 이 결과 지형에 의해 발생하는 이안류가 지배적인 규칙파 조건과 달리 다방향 불규칙파 위상의 상호작용에 따른 돌발적 이안류의 발생이 추가되어 매우 복잡한 쇄파대의 연안 순환흐름을 재현함을 알 수 있었다.

Keywords

References

  1. Battjes, J.A. (1972). Setup due to irregular wave, Proceedings of the 13th Coastal Engineering Conference, Vancouver, ASCE, 1993-2004.
  2. Bowen, A.J. (1969a). The generation of longshore currents on a plane beach, Journal of Marine Research, 27, 206-215.
  3. Bowen, A.J. (1969b). Rip currents, Part 1: Theoretical investigations, Journal of Geophysical Research, 74, 5467-5478. https://doi.org/10.1029/JC074i023p05467
  4. Chen, Q., Dalrymple, R.A., Kirby, J.T., Kennedy, A.B. and Haller, M. (1999). Boussinesq modelling of a rip current system, Journal of Geophysical Research, 104, 20617-20637. https://doi.org/10.1029/1999JC900154
  5. Chen, Q., Kirby, J.T., Dalrymple, R.A., Kennedy, A.B. and Chawla, A. (2000). Boussinesq modeling of wave transformation, breaking and runup II: two horizontal dimensions, Journal of Waterway, Port, Coastal and Ocean Engineering, 126(1), 48-56. https://doi.org/10.1061/(ASCE)0733-950X(2000)126:1(48)
  6. Chen, Q., Kirby, J.T., Dalrymple, R.A., Shi, F. and Thornton, E.B. (2003). Boussinesq modeling of longshore current, Journal of Geophysical Research, 108(C11), 26-1-26-18.
  7. Choi, J., Lim, C.H., Lee, J.I. and Yoon, S.B. (2009). Evolution of waves and currents over a submerged laboratory shoal, Coastal Engineering, 56(3), 297-312. https://doi.org/10.1016/j.coastaleng.2008.09.002
  8. Choi, J. and Yoon, S.B. (2009). Numerical simulations using momentum source wave-maker applied to RANS equation model, Coastal Engineering, 56, 1043-1060. https://doi.org/10.1016/j.coastaleng.2009.06.009
  9. Choi, J., Park, W.K. and Yoon, S.B. (2011) Boussinesq Modeling of a Rip Current at Haeundae Beach. J. of Korean Society of Coastal and Ocean Engineers, 23(4), 276-284 (in Korean). https://doi.org/10.9765/KSCOE.2011.23.4.276
  10. Choi, J. and Yoon, S.B. (2011). Numerical simulation of nearshore circulation on a field topography in a random wave environment, Coastal Engineering, 58, 395-408. https://doi.org/10.1016/j.coastaleng.2010.12.002
  11. Choi, J., Lee, J.I. and Yoon, S.B. (2012a). Surface roller modeling for mean longshore current over a barred beach in a random wave environment, J. Coastal Research, 28(5), 1100-1120.
  12. Choi, J., Park, W.K., Bae, J.S. and Yoon, S.B. (2012b) Numerical Study on a Dominant Mechanism of Rip Current at Haeundae Beach : Honeycomb pattern of waves. J. of the Korean Society of Civil Engineers, 32(5B), 321-320 (in Korean). https://doi.org/10.12652/Ksce.2012.32.5B.321
  13. Choi, J., Lim, C.H. and Yoon, S.B. (2013a). Study of Rip Current Warning Index Function varied according to Real-time Observations. J. of Korea Water Resources Association, 46(5), 477-490 (in Korean). https://doi.org/10.3741/JKWRA.2013.46.5.477
  14. Choi, J., Shin, C.H. and Yoon, S.B. (2013b) Numerical Study on Sea State Parameters Affecting Rip Current at Haeundae Beach : Wave Period, Height, Direction and Tidal Elevation. Journal of Korea Water Resources Association, 46(2), 205-218 (in Korean). https://doi.org/10.3741/JKWRA.2013.46.2.205
  15. Choi, J., Kirby, J.T. and Yoon, S.B. (2015). Boussinesq modeling of longshore currents in the SandyDuck experiment under directional random wave conditions, Coastal Engineering, 101, 17-34. https://doi.org/10.1016/j.coastaleng.2015.04.005
  16. Clark, D. B., Elgar, S. and Raubenheimer, B. (2012). Vorticity generation by short-crested wave breaking, Geophys. Res. Lett., (39), L24604, doi:10.1029/2012GL 054034.
  17. Feddersen, F. (2014). The generation of surfzone eddies in a strong alongshore current, J. Phys. Oceanogr., 44, 600-617. https://doi.org/10.1175/JPO-D-13-051.1
  18. Goda, Y. (2006). Examination of the influence of several factors on longshore current computation with random waves, Coastal Engineering, 53, 157-170. https://doi.org/10.1016/j.coastaleng.2005.10.006
  19. Haas, K. A. and Svendsen, I.A. (2002). Laboratory measurements of the vertical structure of rip currents, J. Geophys. Res., 107(C5), 3047. https://doi.org/10.1029/2001JC000911
  20. Haller, M.C., Honegger, D. and Catalan, P.A. (2014). Rip current observations via Marine Radar. Journal of waterway, port, coastal, and ocean engineering, 140(2), 115-124. https://doi.org/10.1061/(ASCE)WW.1943-5460.0000229
  21. Johnson, D. and Pattiaratchi, C. (2006). Boussinesq modelling of transient rip currents, Coastal Engineering, 53, 419-439. https://doi.org/10.1016/j.coastaleng.2005.11.005
  22. Kennedy, A.B., Chen, Q., Kirby, J.T. and Dalrymple, R.A. (2000). Boussinesq modeling of wave transformation, breaking, and runup. I: 1D, Journal of Waterway, Port, Coastal and Ocean Engineering, 126, 39-47. https://doi.org/10.1061/(ASCE)0733-950X(2000)126:1(39)
  23. Kirby, J.T., Chen, Q., Noyes, T.J., Elgar, S. and Guza, R.T. (2003). Evaluating the low frequency predictions of a Boussinesq wave model: Field cases, Proc. ISOPE-2003, Honolulu, May 25-30, 398-404.
  24. Long, J.W. and Ozkan Haller, H.T. (2009). Low-frequency characteristics of wave group-forced vortices, J. Geophys. Res., 114, C08004, doi:10.1029/2008JC004894.
  25. Longuet-Higgins, M.S. (1970). Longshore currents generated by obliquely incident sea waves: Parts 1 and 2, Journal of Geophysical Research, 75, 6778-6801. https://doi.org/10.1029/JC075i033p06778
  26. Longuet-Higgins, M.S. and Stewart, R.W. (1962). Radiation stress and mass transport in gravity waves with application to 'surfbeats', Journal of Fluid Mechanics, 8, 565-583.
  27. Longuet-Higgins, M.S. and Stewart, R.W. (1964). Radiation stress in water waves, a physical discussion with application, Deep Sea Research, 11, 529-563.
  28. MacMahan, J.H., Thornton, E.B., Stanton, T.P. and Reniers, A.J.H.M. (2005). RIPEX: Observations of a rip current system, Marine Geology, 218, 113-134. https://doi.org/10.1016/j.margeo.2005.03.019
  29. Mitsuyasu, H., Tasai, F., Suhara, T., Mizuno, S., Ohkusu, M., Honda, T. and Rikiishi, K. (1975). Observations of the directional spectrum of ocean waves using a cloverleaf buoy, Journal of Physical Oceanography, 5, 750-760. https://doi.org/10.1175/1520-0485(1975)005<0750:OOTDSO>2.0.CO;2
  30. Noyes, T.J., Guza, R.T., Elgar, S. and Herbers, T.H.C. (2004). Field observations of shear waves in the surfzone, Journal of Geophysical Research, 109, C01031, doi:10.1029/2002 JC001761.
  31. Noyes, T.J. (2002). Field observations of shear waves, Ph.D. thesis, Scripps Institution of Oceanography, La Jolla.
  32. Ozkan-Haller, H.T. and Kirby, J.T. (1999). Nonlinear evolution of shear instabilities of the longshore current: A comparison of observations and computations, J. Geophys. Res., Oceans, 104, 25953-25984. https://doi.org/10.1029/1999JC900104
  33. Peregrine, D.H. (1998). Surf zone currents, Theor. Comput. Fluid Dyn., 10, 295-309. https://doi.org/10.1007/s001620050065
  34. Peregrine, D.H. (1999). Large-scale vorticity generation by breakers in shallow and deep water, Eur. J. Mech. B Fluids, 18, 403-408, doi:10.1016/S0997-7546(99)80037-5.
  35. Sorensen, O.R., Schaffer, H.A. and Madsen, P.A. (1998). Surf zone dynamics simulated by a Boussinesq type model. III. Waveinduced horizontal nearshore circulations, Coastal Engineering, 33 (2), 155-176.
  36. Thornton, E.B. (1970). Variation of longshore current across the surf zone, Proceedings of the 12th Coastal Engineering Conference, 291-308.
  37. Thornton, E.B. and Guza, R.T. (1986). Surf zone longshore currents and random waves: field data and models, Journal of Physical Oceanography, 16, 1165-1178. https://doi.org/10.1175/1520-0485(1986)016<1165:SZLCAR>2.0.CO;2
  38. Van Dongeren, A.R., Reniers, A.J.H.M., Battjes, J.A. and Svendsen, I.A. (2003). Numerical modeling of infragravity wave response during DELILAH, Journal of Geophysical Research, 108, 3288, doi:10.1029/2002JC001332.
  39. Yoon, S.B., Kwon, S.J., Bae, J.S. and Choi, J. (2012). Investigation of Characteristics of Rip Current at Haeundae Beach based on Observation Analysis and Numerical Experiments. J. of the Korean Society of Civil Engineers, 23(4B), 243-251 (in Korean).
  40. Wei, G., Kirby, J.T., Grilli, S.T. and Subramanya, R. (1995). A fully nonlinear Boussinesq model for surface waves: Part 1: Highly nonlinear unsteady waves, Journal of Fluid Mechanics, 294, 71-92. https://doi.org/10.1017/S0022112095002813
  41. Wei, G., Kirby, J.T. and Sinha, A. (1999). Generation of waves in Boussinesq models using a source function method, Coastal Engineering, 36, 271-299. https://doi.org/10.1016/S0378-3839(99)00009-5

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