DOI QR코드

DOI QR Code

Difference of tension on mooring line by buoy type

부이 형상에 따른 부이줄 장력의 차이

  • Lee, Gun-Ho (Aquaculture Industry Division, West Sea Fisheries Research Institute, National Fisheries Research & Development Institute) ;
  • Kim, In-Ok (Aquaculture Industry Division, West Sea Fisheries Research Institute, National Fisheries Research & Development Institute) ;
  • Cha, Bong-Jin (Fisheries System Engineering Division, National Fisheries Research & Development Institute) ;
  • Jung, Seong-Jae (Fisheries System Engineering Division, National Fisheries Research & Development Institute)
  • 이건호 (국립수산과학원 서해수산연구소 해역산업과) ;
  • 김인옥 (국립수산과학원 서해수산연구소 해역산업과) ;
  • 차봉진 (국립수산과학원 시스템공학과) ;
  • 정성재 (국립수산과학원 시스템공학과)
  • Received : 2014.06.03
  • Accepted : 2014.08.25
  • Published : 2014.08.31

Abstract

The difference of mooring tension by type of buoy was investigated in the circulating water channel and the wave tank for deducting the most stable buoy from the current and the wave condition. 5 types of buoy made up of short cylinder laid vertically (CL-V), short cylinder laid horizontally (CL-H), capsule (CS), sphere (SP) and long cylinder (CL-L) were used for experiments. A mooring line and a weight were connected with each buoy. A tensile gauge was installed between a mooring line and a weight. All buoy's mooring tension was measured at the same time for the wave test with periods of 1.5~3.0 sec and wave heights of 0.1~0.3 m, and the current test with flow speeds of 0.2~1.0 m/sec. As a result, the order of tension value in the wave test was CL-H > CL-V > SP > CS > CL-L. In the current test CL-V and CL-H were recorded in the largest tension value, whereas SP has the smallest tension value. So it seems that SP buoy is the most effective in the location affected by fast current. CS is predicted to be suitable for a location that influence of wave is important more than that of current if practical use in the field is considered. And it was found that the difference of mooring tension among buoys in wave is related to the product of the cross sectional area and the drag coefficient for the buoy's bottom side in high wave height. The factor for the current condition was not found. But it was supposed to be related to complex factors like a dimension and a shape by buoy's posture to flow.

Keywords

Buoy;Mooring tension;Water tank experiment;Strong-wind;Loss of fishing gears

Acknowledgement

Grant : 서해안 어구유실 저감기술개발

Supported by : 국립수산과학원

References

  1. Fridman AL. 1986. Calculations for fishing gear designs. Fishing News Books Ltd, Farnham (UK), 66-67.
  2. Brainard EC. 1967. Evaluation of the P.O.E. Buoy with conventional buoy designs. In: Transactions of the 2nd International Buoy Technology Symposium/Exposition, Mar Technol Soc, Washington, D.C., 169-176.
  3. Carpenter EB, Leonard JW and Yim SCS. 1995. Experimental and numerical investigations of tetherd spar and sphere buoys in irregular waves. Ocean Eng 22 (8), 765-784 (DOI: 10.1016/0029-8018 (95)00016-E). https://doi.org/10.1016/0029-8018(95)00016-E
  4. Capobianco R, Reya V and Calve OL. 2002. Experimental survey of the hydrodynamic performance of a small spar buoy. Appl Ocean Res 24, 309-320 (DOI: 10.1016/S0141-1187(03)00026-9). https://doi.org/10.1016/S0141-1187(03)00026-9
  5. Jenkins CH, Leonard JW, Walton JS and Carpenter EB. 1995. Experimental investigation of moored-buoys using advanced video techniques. Ocean Eng 22 (4), 317-335 (DOI: 10.1016/0029-8018 (94)00022-Y). https://doi.org/10.1016/0029-8018(94)00022-Y
  6. Kim WJ and Perkins NC. 2002. Linear vibration characteristics of cable buoy systems. J Sound Vib 252 (3), 443-456 (DOI: 10.1006/jsvi.2001.3849). https://doi.org/10.1006/jsvi.2001.3849
  7. Leonard JW, Idris K and Yim SCS. 2000. Large angular motions of tethered surface buoys. Ocean Eng 27, 1345-1371 (DOI: 10.1016/S0029-8018 (99)00046-3). https://doi.org/10.1016/S0029-8018(99)00046-3
  8. Lin H, Yim SCS and Gottlieb O. 1998. Experimental investigation of response stability and transition behavior of a nonlinear ocean structural system. Ocean Eng 25 (4-5), 323-43 (DOI: 10.1016/S0029-8018 (97)00023-1). https://doi.org/10.1016/S0029-8018(97)00023-1
  9. Radhakrishnan S, Datla R and Hires RI. 2007. Theoretical and experimental analysis of tethered buoy instability in gravity waves. Ocean Eng 34, 261-274 (DOI: 10.1016/j.oceaneng.2006.01.010). https://doi.org/10.1016/j.oceaneng.2006.01.010
  10. Sundaravadivelu R, Babu MH and Murugaganesh R. 1991. Experimental investigation on a single point buoy mooring system, Ocean Eng 18 (5), 405-417 (DOI: 10.1016/0029-8018(91)90022-I). https://doi.org/10.1016/0029-8018(91)90022-I
  11. Umar A and Datta TK. 2003. Nonlinear response of a moored buoy, Ocean Eng 30, 1625-1646 (DOI: 10.1016/S0029-8018(02)00144-0). https://doi.org/10.1016/S0029-8018(02)00144-0
  12. White FM. 2003. Fluid mechanics 5th Edition. McGraw-Hill, Korea, 519-523.
  13. Williamson CHK and Govardhan R, 1997. Dynamics and forcing of a tethered sphere in a fluid flow. J Fluid Struct 11, 293-305 (DOI: 10.1006/jfls.1996.0078). https://doi.org/10.1006/jfls.1996.0078
  14. Zhang SX, Tang TG and Liu XJ. 2012. Experimental investigation of nonlinear dynamic tension in mooring lines. J Mar Sci Technol 17, 181-186. https://doi.org/10.1007/s00773-012-0160-7

Cited by

  1. Effect of the characteristics of buoy on the holding power of trapnet vol.53, pp.4, 2017, https://doi.org/10.3796/KSFT.2017.53.4.309