An estimated angle of attack of a cambered otter board in a bottom trawl using three dimensional position

저층 트롤에서 3차원 위치를 이용한 만곡형 전개판의 영각 추정

  • Received : 2014.10.07
  • Accepted : 2015.02.17
  • Published : 2015.02.28


The angle of attack of a cambered otter board in a bottom trawl was estimated using a three-dimensional semi-analytic treatment of a towing cable (warp) system that was applied to the field experiments of a bottom trawl obtained by the Scanmar system. The equilibrium condition of the horizontal component and vertical component of forces was used to the three forces acting on the otter board in the horizontal plane. Those forces were the force on the warp at the bracket, hydrodynamic lift and drag forces on the otter board and the force on the hand rope attached just behind the otter board. Also the equilibrium of moment about the front edge of the otter board was used to find out the angle of attack of the cambered otter board. When the warp length was 120m and 180m long and the towing speed was between 1.23 and 1.90 m/s, the estimated angle of attack of the cambered otter board was ranged between $26.1^{\circ}$ and $29.6^{\circ}$, respectively, though the maximum lift force was at the angle of attack $22.6^{\circ}$. The angle of attack of the otter board was tended to increase weakly with the longer length of warp (180 m) at the same towing speed in the experiment.


Otter board;Angle of attack;Lift;Drag;Moment;Bottom trawl


  1. Bae JH. 2000. Experiment with spread force characteristics of rotating circular cylinder. Master thesis. Pukyong National University, Korea. p. 35 (in Korean).
  2. Buxton NG and DeAlteris JT. 1993. Qualification of water flow and net drag in midwater trawls. Fish Res 16, 165-178. (doi:10.1016/0165-7836(93)90050-H)
  3. Chang JW. 1968. A study on one boat midwater trawl. Bull Pusan Fish Coll 8(1), 1-12.
  4. Chang JW and Seo DO. 1982. Fishing Gear Engineering. Shinhan, Busan,, p. 304 (in Korean).
  5. Cho BK and Cho SO. 2000. A study on the bottom trawl gear by the trial of a stern trawler I - On the resistance of a bottom trawl gear. Bull. Kor Soc Fish Technol 36(4), 274-280 (in Korean).
  6. Cho BK and Go GS. 2000. A study on the bottom trawl gear by the trial of a stern trawler II - On the net shape of a bottom trawl gear. Bull Kor Soc Fish Technol 36(4), 281-286 (in Korean).
  7. Crewe PR. 1964. Some of the general engineering principles of trawl gear design. Modern fishing gear of the world-II, Fishing News Ltd., 165-180.
  8. Engas A. 1994. The effects of trawl performance and fish behaviour on the catching efficiency of demersal sampling trawls. In: A. Ferno and S. Olsen, editors. Marine fish behaviour in capture and abundance estimation. Fishing News Books, Blackwall Science Ltd., London, pp. 45-68.
  9. FAO. 1974. Otter board design and performance. FAO fishing manuals, Rome, p. 82.
  10. Fridman AL. 1986. Calculations for fishing gear designs. FAO Fishing Manuals, Fishing News Books Ltd., Farnham, UK, pp 153-184 (revised by PJG Carrothers).
  11. Hu F and Matuda K. 1991. An analytical method of static characteristics of midwater trawl system. Nippon suisan gakkaishi 57(4), 661-666 (in Japanese).
  12. Hu F, Oozeki Y, Tokai T and Matuda K. 2001. Scale model of a new midwater trawl system for sampling pelagic larval and juvenile fish. Fish Sci 67, 254-259.
  13. Huang S and Vassalos D. 1993. A semi-analytic treatment of three dimensional statics of marine cables. Ocean Eng 20(4), 409-420. (doi:10.1016/0029-8018(93)90004-2)
  14. Jang CS and Lee BG, 1996. A study on the midwater pair trawing-IV. Bull. Korean Soc Fish Technol 32(1), 7-15 (in Korean).
  15. Kawakami T. 1959. Development of mechanical studies of fishing gear. In Modern Fishing Gear of the world I, Kristjonsson H. (ed.), pp 175-184. FAO, Rome.
  16. Kawakami T. 1981. Introduction to Fisheries Analysis. Koseisa, Tokyo, p. 294. (in Japanese).
  17. Kim IJ and Lee CW. 1999. Analysis of the net mouth shape for a midwater trawl gear. Bull Korean Soc Fish Technol 35, 118-128 (in Korean).
  18. Ko KS, Kwon BG, Lee GH and Ro KD. 1991. Computation fluid analysus for the otter boards -3 Efficiency analysis of the single cambered otter boards for the various slot position. Bull Korean Soc Fish Technol 27(4), 278-285 (in Korean).
  19. Koyama T, Kudo T and Oba O. 1981. Drag and sheer of the Suberkrub type trawl boards. Bull Nat'l Res Inst Fish Eng 2, 95-103 (in Japanese).
  20. Kwon BG and Ko KS. 1994. Model test on the three-slot cambered otter board with accessories. Bull Korean Soc Fish Technol 30(2), 71-77 (in Korean).
  21. Lee BG, Kim JK, Choe JH and Chang HY. 1987. Study on the midwater trawl available in the Korean waters-IV. Bull Korean Soc Fish Technol 23, 6-10 (in Korean).
  22. Lee CW, Lee JH and Kim IJ. 2000. Application of a fuzzy controller to depth control of a midwater trawl net. Fish Sci 66(5), 858-862.
  23. Lee CW, Lee JW, Cha BJ, Kim HY and Lee JH. 2005. Physical modeling for underwater flexible systems dynamic simulation. Ocean Eng 32, 331-347. (doi:10.1016/j.oceaneng.2004.08.007)
  24. Lee CW, Zhang CI and Shin HO. 2001. simplified trawl system modeling and design of a depth control system using fuzzy logic. Fish Res 53, 83-94. (doi:10.1016/S0165-7836(00)00264-2)
  25. Lee GH, Lee CW, Kim YB, Pingguo H and Choe MY. 2008. Simulation of the virtual mackerel behavior to the trawl gear. J Kor Soc Fish Technol 44(1), 10-19 (in Korean).
  26. Lin J, Sato D, Nashimoto K and Yamamoto K. 1989. Efficiency and stability of saucer-shaped otter boards with changing attack angle and heel angle. Nippon suisan gakkaishi 55(2), 295-300 (in Japanese).
  27. Matuda K (ed). 2001. Fishing gear physics. Seizando, Tokyo, p 226 (in Japanese).
  28. Matuda K, Hu F and Ishigawa S. 1990. Hydrodynamic characteristics of vertical V type otter board. Nippon suisan gakkaishi 56(11), 1815-1820 (in Japanese).
  29. Matuda K, Hu F, Satoh K, Saotome Y and Kasuga I. 1991. Field experiment on static characteristics of midwater trawl system. Nippon suisan gakkaishi 57(4), 655-660 (in Japanese).
  30. Park CD and An HC. 2002. A study on the static stability of the otter board in relation to the angle of attack. Bull Korean Soc Fish Technol 38(3), 234-240 (in Korean).
  31. Park HH. 1993. A tension measurement method of a towing cable or a buoy cable. Ocean Eng 20(2), 163-170. (doi:10.1016/0029-8018(93)90032-D)
  32. Park HH. 2005. An estimating method of the angle of attack of a vertical V-type otter board. Bull Korean Soc Fish Technol 41, 113-121 (in Korean).
  33. Park HH. 2007. A method for estimating the gear shape of a mid-water trawl. Ocean Eng 34, 470-478. (doi:10.1016/j.oceaneng.2006.03.001)
  34. Park HH. 2014. The geometrical gear shape of a bottom trawl. Ocean Eng 89, 53-61. (doi: 10.1016/j.oceaneng.2014.06.034)
  35. Park HH, Cho BK, Go GS and Chang HY. 2008. The gear shape and cross section of sweep at mouth of a bottom trawl. J Kor Soc Fish Technol 44(2), 120-128 (in Korean).
  36. Park HH and Yae YH. 1999. Use of cable functions by Pode's analysis in a towing cable or a buoy cable. Bull Korean Soc Fish Technol 35(4), 353-358 (in Korean).
  37. Park KH, Lee JH, Hyun BS and Bae JH. 2001. The study on the hydrodynamic characteristics of the single slot cambered otter board. Bull Korean Soc Fish Technol 37(1), 1-8 (in Korean).
  38. Prat JJ, Antonijuan A, folch A, Sala A, Lucchetti A, Sarda F and Manuel A. 2008. A simplified model of the interaction of the trawl warps, the otterboards and netting drag. Fish Res 94(1), 109-117. (doi:10.1016/j.fishres.2008.07.007)
  39. Sangster GI and Breen M. 1998. Gear performance and catch comparison trials between a single trawl and a twin rigged gear. Fish Res 36, 15-26. (doi:10.1016/S0165-7836(98)00086-1)
  40. Sato K and Miyazaki Y. 1984. A study on an approximate calculation for towing fishing gears. Bull Japanese Soc Sci Fish 50(5), 793-804 (in Japanese).
  41. Stewart PAM and MacLennan DN. 1987. Fishing gear technology. In: Bailey, R.S., Parrish, B.B. (Eds.), Developments in fisheries research in Scotland, Fishing News Books, Surrey, pp. 123-138.
  42. Suberkrub F. 1959. Otter boards for pelagic trawling. Modern fishing gear of the world-I, Fishing News Ltd., 359-360.