|Table of Contents|

Improved draft survey method based on densified table of offsets(PDF)

《交通运输工程学报》[ISSN:1671-1637/CN:61-1369/U]

Issue:
2014年03期
Page:
58-64
Research Field:
载运工具运用工程
Publishing date:

Info

Title:
Improved draft survey method based on densified table of offsets
Author(s):
LIU Chun-lei;  ZHANG Xiu-feng;  SUN Xiao-feng;  YIN Yong
Key Laboratory of Marine Simulation and Control of Ministry of Communications, Dalian Maritime University, Dalian 116026, Liaoning, China
Keywords:
ship engineering;  draft survey;  densified table of offsets;  floating state parameters;  S-H clipping algorithm;  free floatation;  displacement
PACS:
U693.4
DOI:
-
Abstract:
In order to improve the accuracy of draft survey, an improved draft survey method that did not depend on ship loading manual was developed. The displacement of ship was calculated by using high-precision ship database that was established based on the densified table of offsets. The floating state parameters and sagging(hogging)value of ship were calculated according to six draft readings. In order to calculate the sagging(hogging)value of each station, the deformation curve of ship was fitted by circular arc according to the beam bending theory in material mechanics. The ship database in sagging(hogging)condition was constructed by the correction of offsets coordinate point. The displacement of ship in free floatation was calculated by using floating state parameters, coordinate system transformation and S-H polygon clipping algorithm. Taking a bulk carrier as an example, the displacements of ship in even keel, trim and hogging condition were calculated respectively, and compared with the calculation result of traditional draft survey method. Calculation result indicates that in even keel condition, the average relative error of improved draft survey method is smaller, about 0.085 6%, the average relative errors increase to 0.414 5% and 0.619 9% in trim and hogging condition respectively. The calculation accuracy of improved draft survey method increases, the method can be applied to free floatation of ship, and has a certain engineering application value. 4 tabs, 15 figs, 19 refs.

References:

[1] 郑士源,姚祖洪.国际干散货航运市场的评价[J].交通运输工程学报,2004,4(4):88-92.ZHENG Shi-yuan, YAO Zu-hong. Evaluation of international dry bulk shipping market[J]. Journal of Traffic and Transportation Engineering, 2004, 4(4): 88-92.(in Chinese)
[2] 林火平.散货船水尺检量中计算所得船舶常数的误差[J].航海技术,1996(6):26-27.LIN Huo-ping. The constant error of bulk carrier draft survey[J]. Marine Technology, 1996(6): 26-27.(in Chinese)
[3] 王淑敏,方卫东.水尺计重实施中几个问题的研究[J].大连海事大学学报,1998,24(1):79-82.WANG Shu-min, FANG Wei-dong. Research on the deviation and calibration of constant in draft survy[J]. Journal of Dalian Maritime University, 1998, 24(1): 79-82.(in Chinese)
[4] 陈建锋.影响散货船压载水准确测算的因素[J].航海技术,2003(5):20-22.CHEN Jian-feng. Element of influence of ballast water sounding and calculation[J]. Marine Technology, 2003(5): 20-22.(in Chinese)
[5] 李清林.水尺检量中吃水差和船舶长度适用问题的分析[J].世界海运,2007,30(3):41-42.LI Qing-lin. Correspondence of ship’s length and trim in draft survey calculation[J]. Word Shipping, 2007, 30(3): 41-42.(in Chinese)
[6] 黄昱洪.大纵倾情况下船舶排水量的精确测定[J].中国水运,2009,9(7):34-35.HUANG Yu-hong. Accurate determination of tonnage in large trim condition[J]. China Water Transport, 2009, 9(7): 34-35.(in Chinese)
[7] 刘辉强.水尺计重及其误差分析[D].大连:大连海事大学,2010.LIU Hui-qiang. Draft survey and error analysis[D]. Dalian:Dalian Maritime University, 2010.(in Chinese)
[8] RAN Xin, SHI Chao-jian, CHEN Jin-biao, et al. Draft line detection based on image processing for dhip draft survey[C]∥GAOL F L, NGUYEN Q V. Proceedings of the 2011 2nd International Congress on Computer Applications and Computational Science. Warszawa: Springer, 2011: 39-44.
[9] GU Hong-wei, ZHANG Wang, XU Wen-hai, et al. Digital measurement system for ship draft survey[J]. Applied Mechanics and Materials, 2013, 333-335: 312-316.
[10] ZIHA K. Displacement of a deflected ship hull[J]. Marine Technology and Sname News, 2002, 39(1): 54-63.
[11] IVCE R, JURDANA I, MOHOVIC R. Determining weight of cargo onboard ship by means of optical fibre technology draft reading[J]. PROMET—Traffic and Transportation, 2011, 23(6): 421-429.
[12] 刘春雷,张秀凤,孙霄峰,等.基于加密型值表的船舶静水力特性精确计算[J].中国造船,2013,54(4):163-172.LIU Chun-lei, ZHANG Xiu-feng, SUN Xiao-feng, et al. Hydrostatic performance calculation of vessel based on densified table of offsets [J]. Shipbuilding of China, 2013, 54(4): 163-172.(in Chinese)
[13] 刘春雷.散货船智能化配载仪的研究与实现[D].大连:大连海事大学,2013.LIU Chun-lei. Research and implementation of intelligent bulk carrier stowage system[D]. Dalian: Dalian Maritime University, 2013.(in Chinese)
[14] 陆丛红,林 焰,纪卓尚.基于NURBS表达的船舶静水力特性精确计算[J].船舶力学,2007,11(5):691-701.LU Cong-hong, LIN Yan, JI Zhuo-shang. Precise calculation of ship hydrostatic performances based on NURBS shipform[J]. Journal of Ship Mechanics, 2007, 11(5): 691-701.(in Chinese)
[15] 陆丛红,林 焰,纪卓尚.基于曲面表达的几何特性计算及其在船舶工程中的应用[J].哈尔滨工程大学学报,2005,26(6):697-703.LU Cong-hong, LIN Yan, JI Zhuo-shang. Geometric properties calculation based on surface representation and its application to ship engineering[J]. Journal of Harbin Engineering University, 2005, 26(6): 697-703.(in Chinese)
[16] 赵晓非,林 焰.关于解船舶浮态问题的矩阵方法[J].中国造船,1985,26(3):55-64.ZHAO Xiao-fei, LIN Yan. Matrix methods for solving ship floating state problem[J]. Shipbuilding of China, 1985, 26(3): 55-64.(in Chinese)
[17] 林 焰,李铁骊,纪卓尚.破损船舶自由浮态计算[J].大连理工大学学报,2001,41(1):85-89.LIN Yan, LI Tie-li, JI Zhuo-shang. Ship damage floating calculation[J]. Journal of Dalian University of Technology, 2001, 41(1): 85-89.(in Chinese)
[18] MAILLOT P G. A new, fast method for 2D polygon clipping: analysis and software implementation[J]. ACM Transactions on Graphics, 1992, 11(3): 276-290.
[19] RAPPOPORT A. An efficient algorithm for line and polygon clipping[J]. The Visual Computer, 1991, 7(1): 19-28.

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Last Update: 2014-06-30