Experimental analysis of the interaction between the unidirectional flow and spoiler on mechanism of self burial pipelines

Document Type : Original Article

Authors

1 PhD graduate of hydraulic structure.,Water Eng.Dep , International Campus of Ferdowsi University of Mashhad, Mashhad, Iran

2 Professor., Department of Water Science and Engineering., Ferdowsi University of Mashhad, Mashhad, Iran

3 water science and engineering. ferdowsi university of mashhad- mashhad -Iran

Abstract

To stimulate the artificial self-burial of pipelines to provide safe conditions in erodible beds, the spoiler can be used at the top of the pipeline. The study of the performance of the spoiler that mounted on the naturally moveable pipe is a major gap that not founded in previous research. In this experimental study the parameters affecting the self-burial process of the pipelines were investigated. An equation was proposed for estimating the depth of self-burial in the normal settling of the pipe and was found that the moveable pipe decrease the scour depth by 54 percent in comparison with the fixed pipe. Maximum change in self –buried was obtained at S=D (S is the length of spoiler & D is the diameter of the pipe) that was equal to 70 and 67 percent of the diameter of the pipe in fine and coarse beds, respectively. The length of Lee-wake erosion in the pipe with natural motion was greater than in which the fixed pipe and increase with installed spoiler and spoiler height increases. Maximum length of Lee-wake erosion happened when S=D. The most burying is at zero degrees of the spoiler to the vertical axis.

Keywords

References

Barendse,C.A.M. 1988. Hydrodynamic forces on a near-bed offshore pipeline with spoiler during the selfburying process. Thesis Report, Delft University of Technology, Faculty of Civil Engineering.
Bijker,E.W and Leeuwestein,W. 1984. Interaction between pipeilines and theseabed under the influence of waves and currents.  Seabed Mechanics, Edited Proceedings of a Symposium. 235-242
Cheng,L and Chew,L.W.  2003. Modelling of flow around a near-bed pipeline with a spoiler. Ocean Engineering. 30.13: 1595-1611.
Chiew,Y. 1990. Mechanics of local scour around submarine pipelines. Journal of Hydraulic Engineering. 116.4: 515–529.
Chiew,Y.M. 1992. Effect of spoilers on scour at submarine pipelines. Journal of Hydraulic Engineering. ASCE. 118.9: 1311-1317.
Chiew,Y. 1993. Effect of spoilers on wave-induced scour at submarine pipelines. Journal of Waterway, Port, Coastal, and Ocean Engineering. ASCE. 119.4: 417-429.
Dey,S and Singh,N.P. 2008. Clear-water scour below underwater pipelines understeady flow. Journal of Hydraulic Engineering, ASCE. 134: 588-600.
Fei,X.Y., Ning,G.J., Bin,N.E., Kizhikkilod,J.,  Le,T.S and Zhao,D. 2004. The Hangzhou bay pipeline crossing project use of spoilers to initiate pipeline self-burial and re-initiate future re-buria. International Conference on Scour and Erosin. Singapor. 2: 506-521.
Fredsoe,J., Hansen,E.A., Mao,Y. and B.M. Sumer. 1988. Three-dimensional scour below pipelines. Journal of Offshore Mechanics and Arctic Engineering. 110: 373-379.
 Fredsoe,J., Sumer,B.M and Arnskov,M. 1992. Time scale for wave/current scour below pipelines. International Journal of Offshore and Polar Engineering. 2.2: 13-17.
Hulsbergen,C.H. 1984. Stimulated self-burial of submarine pipelines. Proceedings of the 16th Offshore Technology Conference. Houston. Texas. 171-178.
Hulsbergen,C. H. 1986. Spoilers for stimulated self-burial of submarine pipelines. Proceedings of the 18th Offshore Technology Conference. Houston. Texas. 441-444.
Hulsbergen,C.H., Bijker,R. 1989. Effect of spoilers on submarine pipeline stability. Proceedings of the 21 th Offshore Technology Conference, Houston. Texas. 337-350.
Ibrahim,A and Nalluri,C. 1986. Scour prediction around marine pipelines. Proceedings of the 5th International Symposium on Offshore Mechanics and Arctic Engineering ,Tokyo, Japan. 679-684.
Lee,W., Hur,D., Kim,H and Jo,H. 2016.   Numerical Analysis on Self-Burial Mechanism of Submarine Pipeline with Spoiler under Steady Flow. Journal of Korean Society of Coastal and Ocean Engineers. 146: 146-159.
Mao,Y. 1986. The interaction between a pipeline and an erodible bed. Series Paper Technical University of Denmark, Issue 39.
Mellvil,B.W. 1997. Pier and abutment scour. Integrated approach. Journal of Hydraulic Engineering. ASCE.132: 125-136.
Moncada,A.T.,Aguirre-Pe, J. 1999. Scour below pipeline in rivercrossings. Journal of Hydraulic Engineering. ASCE. 125: 953-958.
Oner,A. 2016. Numerical investigation of flow around a pipeline with a spoiler near a rigid bed. Advances in Mechanical Engineering. 8.6: 1-13
Kjeldsen,S.P., Gjorsvik,O., Bringaker, K.G and Jacobsen ,J. 1973. Local scour near offshore pipelines. Second International Port and Ocean Engineering under Arctic Conditions Conference. 308-331.
Shan,M., Mao,Y. 1986. The interaction between a pipeline and an erodible bed. Series paper 39. Ph.D. thesis Technical University of Denmark.
Shan,D. Liu,Y and LI,Y.  2015. Numerical simulation of submarine pipeline self-buried on sediment seabed. Advances in Petroleum Exploration and Development. 10.1:
Sumer,B.M and Fredsoe,J. 1990. Scour below pipelines in waves. Journal of Waterway, Port, Coastal, and Ocean Engineering. 116: 307-323
Sumer,B.M., Truelsen,C., Sichmann,T and Fredsoe,J. 2001. Onset of scour below pipelines and self-burial. Coastal Engineering. 42: 313-335.
Sumer,B.M and Fredsoe,J.  2002. The mechanics of scour in the marine environment. Advanced Series on Ocean Engineering .Volume 17.
Van Beek, F.A and Wind, H.G. 1990. Numerical modelling of erosion and sedimentation around pipelines. Coastal Engineering, 14:107-128.
Zhao,Z.H and Fernando,H.J.S.  2008. Numerical modeling of a sagging pipeline using an eulerian two-phase model. Journal of Turbulence. 9: 1-20.
Zhu,H., Qi,X., Lin,P and Yang,Y. 2013. Numerical simulation of flow around a submarine pipe with a spoiler and currentinduced scour beneath the pipe. Applied Ocean Research. 41: 87-100.
Iranian Journal of Irrigation & Drainage
Volume 11, Issue 6 - Serial Number 66
March and April 2018
Pages 960-971

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