Journal of the Society of Naval Architects of Korea (대한조선학회논문집)

The Society of Naval Architects of Korea (대한조선학회)
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Linear Analysis of Water Surface Waves Generated by Submerged Wave Board Whose Upper and Lower Ends Oscillate Horizontally Freely

상하단이 자유롭게 수평동요하는 수중 조파판에 의해 생성된 수면파의 근사해석

  • Kim, Hyochul (Department of Naval Architecture and Ocean Engineering, Seoul National University.Institute of Engineering Research) ;
  • Oh, Jungkeun (Department of Naval Architecture and Ocean Engineering, Kunsan National University) ;
  • Kwon, Jongoh (Korea Intellectual Property Office) ;
  • Lew, Jae-Moon (Department of Naval Architecture and Ocean Engineering, Chungnam National University)
  • 김효철 (서울대학교 조선해양공학과.서울대학교 공학연구원) ;
  • 오정근 (군산대학교 조선해양공학과) ;
  • 권종오 (특허청) ;
  • 류재문 (충남대학교 선박해양공학과)
  • Received : 2018.08.07
  • Accepted : 2019.07.13
  • Published : 2019.10.20
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Abstract

To derive a simplified analytic solution which can be utilized as a fundamental solution for the wave maker design, a segment of the wave board has been idealized as a submerged line segment in a two dimensional domain of a wave flume. The lower end of the line segment could be located at arbitrary depth of the wave flume and the upper end of the board could be also submerged to any depth from the free surface. The freely oscillating motion of the wave board is assumed to be defined by determining the condition of horizontal oscillation on both ends differently. The submerged wave board oscillating in horizontal direction could be specified by selecting the amplitude, frequency and the phase lag differently on lower and upper ends of the board. The simplified two dimensional wave generated by the wave board segment has been obtained by the first order perturbation method. It is found that the general solution of the freely oscillating wave board in two dimensional domain could be decomposed into the solution of flap motion with lower end hinge and swing motion with upper end hinge. The case study of the analytic solutions has been carried out to evaluate the effect on the wave height due to the difference of oscillation frequency, phase difference and variation of stroke between for the motion of both ends. It is found that the solution of the freely oscillating wave board could be utilized for the development of high performance wavemaker especially for irregular waves.

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References

  1. Dean, R.G. & Dalrymple, R.A., 2007, Water wave mchanics for engineers and scientists, World Scientific (Advanced series on Ocean Engineering), New Jersey.
  2. Hughes, S.A., 1993, Physical Model and Laboratory Techniques in Coastal Engineering, USA.
  3. Hyun, J.M., 1976, Theory for Hinged Wavemakers of Finite Draft in water of Constant Depth, Journal of Hydronautics, Vol 10, No. 1, pp.2-7. https://doi.org/10.2514/3.63046
  4. Kim, H., Lew, J.M., Oh, J., Kim, J.S., Kim, W.S., Kim, I.H. & Kim, W.J., Wave generator for ship model test with wave board which oscillating in dual mode, KR Patent 10-2018-0019183, filed Feb. 19, 2018A.
  5. Kim, H., Lew, J.M., Oh, J., Kim, J.S., Kim, W.S., Kim, I.H. & Kim, W.J., Wave generator composed with wave board and appended reinforcing flap for ship model test, KR Patent 10-2018-000296, filed Jan. 2, 2018B.
  6. Khalilabadi, M.R. & Bidokhti, A.A., 2012, Design and construction of an optimum wave flume, Journal of Applied Fluid Mechanics, 5(3), pp.99-103.
  7. Kwon, J.O., Kim, H., Lew,J.M. & Oh, J., 2017A, Analytic solution of oscillating submerged vertical board segment by perturbation method and its characteristics, Korean Towing Tank Conference Spring Meeting, Inha University.
  8. Kwon, J.O., Kim, H., Lew, J.M. & Oh, J., 2017B, Simplified analyitic solution of submerged wave board motion and its application on the design of wave generator, Journal of the Society of Naval Architects of Korea, 54(6), pp.461-469. https://doi.org/10.3744/SNAK.2017.54.6.461
  9. Liao, S.W. & Roddier, D., 1998, Simulation of breaking waves-Theory and Experiments, Society of Naval Architects and Marine Engineers(SNAME) North California Section.
  10. Oh, J., Kim, J.Y., Kim, H., Kwon, J.O. & Lew, J.M., 2017, Approximate solution of vertical wave board oscillating in submerged condition and its design application, 2017 Annual Autumn Conference, The Society of Naval Architects of Korea, Yeosu EXPO.
  11. Wang, S., 1974, Plunger-type wavemakers: Theory and experiment. Journal of Hydraulic Research, 12(3), pp.357-388. https://doi.org/10.1080/00221687409499732
  12. Takezawa, S., 1980, Waves of the wave basin for the offshore structure experiments, Journal of the Society of Naval Architects of Japan, 613, pp.376-387.
  13. Halfiani, V., Muraif & Ramli, M., 2015, Triple-flap wavemaker based on linear wave theory, Bulletin of Mathematics, Vol. 07, No. 01.