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Risk free zone study for cylindrical objects dropped into the water

  • Xiang, Gong (School of Naval Architecture and Marine Engineering, University of New Orleans) ;
  • Birk, Lothar (School of Naval Architecture and Marine Engineering, University of New Orleans) ;
  • Li, Linxiong (Department of Mathematics, University of New Orleans) ;
  • Yu, Xiaochuan (School of Naval Architecture and Marine Engineering, University of New Orleans) ;
  • Luo, Yong (School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University)
  • 투고 : 2016.08.18
  • 심사 : 2016.11.07
  • 발행 : 2016.12.25

초록

Dropped objects are among the top ten causes of fatalities and serious injuries in the oil and gas industry (DORIS, 2016). Objects may accidentally fall down from platforms or vessels during lifting or any other offshore operation. Proper planning of lifting operations requires the knowledge of the risk-free zone on the sea bed to protect underwater structures and equipment. To this end a three-dimensional (3D) theory of dynamic motion of dropped cylindrical object is expanded to also consider ocean currents. The expanded theory is integrated into the authors' Dropped Objects Simulator (DROBS). DROBS is utilized to simulate the trajectories of dropped cylinders falling through uniform currents originating from different directions (incoming angle at $0^{\circ}$, $90^{\circ}$, $180^{\circ}$, and $270^{\circ}$). It is found that trajectories and landing points of dropped cylinders are greatly influenced by the direction of current. The initial conditions after the cylinders have fallen into the water are treated as random variables. It is assumed that the corresponding parameters orientation angle, translational velocity, and rotational velocity follow normal distributions. The paper presents results of DROBS simulations for the case of a dropped cylinder with initial drop angle at $60^{\circ}$ through air-water columns without current. Then the Monte Carlo simulations are used for predicting the landing point distributions of dropped cylinders with varying drop angles under current. The resulting landing point distribution plots may be used to identify risk free zones for offshore lifting operations.

키워드

참고문헌

  1. Aanesland, V. (1987), "Numerical and experimental investigation of accidentally falling drilling pipes", Annual OTC in Houston, Texas, April 27-30.
  2. American Bureau of Shipping, (2013), Guidance notes on accidental load analysis and design for offshore structures, ABS, Houston, TX, USA.
  3. Awotahegn, M.B. (2015), Experimental investigation of accidental drops of drill pipes and containers, Master Thesis, University of Stavanger.
  4. Chu, P.C., Gilles, A. and Fan, C.W. (2005), "Experiment of falling cylinder through the water column", J. Exper. Therm. Fluid Sci., 29(5), 555-568. https://doi.org/10.1016/j.expthermflusci.2004.08.001
  5. Chu, P.C. and Fan, C.W. (2006), "Prediction of falling cylinder through air-water-sediment columns", J. Appl. Mech. Rev. - ASME, 73, 300-314. https://doi.org/10.1115/1.2125975
  6. Colwill, R.D. and Ahilan, R.V. (1992), "Reliability analysis of the behavior of dropped objects", 24th Annual OTC in Houston, Texas
  7. DNV (1996), Worldwide offshore accident databank (WOAD), version4.11
  8. DNV (2010), Risk assessment of pipeline protection, RP-F107
  9. Dropped Objects Register of Incidents & Statistics (DORIS) (2016), http://www.doris.dropsonline.org/
  10. Dubi, A. (2000), Monte Carlo applications in systems engineering. Wiley, West Sussex, U.K.
  11. Glenn Research Center (1941), Kutta-Joukowski lift theorem for a cylinder https://www.grc.nasa.gov/www/k-12/airplane/cyl.html (accessed 16.03.15)
  12. Hoerner, S.F. (1958), Fluid dynamics drag, Bricktown, NJ
  13. John, M.S. and Francis, E.P. (1962), Six-degree-of-freedom equations of motion for a maneuvering re-entry vehicle, Technical Report, NAVTRADEVCEN 801A
  14. Luo, Y. and Davis, J. (1992), "Motion simulation and hazard assessment of dropped objects", Proceedings of the 2nd International Offshore and Polar Engineering Conference, ISBN 1-880653-04-4 San Francisco, USA.
  15. Mood, A.M., Graybill, F.A. and Boes, D.C. (1974), Introduction to the theory of statistics, McGraw- Hill Book Company, New York
  16. Majed, A. and Cooper, P. (2013), "High fidelity sink trajectory nonlinear simulations for dropped subsea objects", Proceedings of the 23rd International Offshore and Polar Engineering Conference, AK,USA
  17. Nagle, R.K., Saff, E.B. and Snider, A.D. (2008), Fundamentals of differential equations and boundary value problems, 5th Ed., Pearson Education, Inc. Boston, Massachusetts.
  18. Newman, J.N. (1977), Marine hydrodynamic, The MIT Press, Cambridge, Massachusetts.
  19. Rouse, H. (1938), Fluid mechanics for hydraulic engineers, 1st Ed., McGraw-Hill Book Company, New York.
  20. Schlichting, H. (1979), Boundary layer theory, McGraw-Hill Book Company, New York.
  21. Wei, Z.Y. and Hu, C.H. (2015), "Experimental study on water entry of circular cylinders with inclined angles", J. Mar Sci. Technol., 20(4), 722-738. https://doi.org/10.1007/s00773-015-0326-1
  22. Wittwer, J.W. (2004), Monte Carlo simulation Basics, http://vertex42.com/ExcelArticles/mc/MonteCarloSimulation.html (accessed 16.05.26)
  23. Xiang, G., Birk, L., Yu, X.C. and Lu, H.N. (2016a), "Numerical study on the trajectory of dropped cylindrical objects", Submitted to J. Ocean Engineering.
  24. Xiang, G., Birk, L., Yu, X.C. and Li, X. (2016b), "Study on the trajectory and landing points of dropped cylindrical object with different longitudinal center of gravity", Submitted to J. ISOPE.
  25. Yasseri, S. (2014), "Experiment of free-falling cylinders in water", Underwater Technol., 32(2), 177-191. https://doi.org/10.3723/ut.32.177

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