Deniz Boru Hattı Dinamik Davranışının Sonlu Elemanlar Yöntemi İle Analizi

Year 2019, Volume: 23 Issue: 2, 404 - 410, 25.08.2019

Begüm Yurdanur Dağlı , Dilay Uncu , Yeşim Tuskan

https://doi.org/10.19113/sdufenbed.494460

Cited By: 1

Abstract

Bu
çalışmada hidrodinamik kuvvetlere maruz kalan deniz boru hattının dinamik
davranışı Sonlu Elemanlar Yöntemi kullanılarak incelenmiştir. Dalga
parametreleri Stokes 3. Mertebe Dalga Teorisi kullanılarak hesaplanmıştır.
Dalga periyodu boyunca değişen sürükleme, atalet ve kaldırma kuvvetleri Morison
Denklemi ile belirlenmiştir. Zaman Tanım Alanında Analiz yaklaşımı dikkate
alınarak bir önceki kuvvet nedeni ile deforme olan sistem üzerine yeni yükleme
yapılmıştır. Sonlu Elemanlar Yöntemi ile periyot süresince kritik kesit
deplasman değerleri hesaplanmıştır. Elde dilen maksimum deplasmanlar, akış
analizini yapısal analiz ile birleştiren ANSYS-FSI (Fluid
Structure Interaction) tekniği
ile belirlenen değerler ile karşılaştırılmıştır. İki analize ilişkin sonuçların
tutarlı olması Sonlu Elemanlar Yönteminin eş değer dinamik analiz yapmak için
kullanılabileceğini göstermektedir.

Keywords

Hidrodinamik kuvvet, Sonlu elemanlar yöntemi, Stokes 3. mertebe dalga teorisi

Analysis of Dynamic Behaviour of Marine Pipelines with Finite Elements Method

Abstract

In
this study, the dynamic behaviour of the marine pipeline subjected to
hydrodynamic forces are investigated by using the Finite Element Method. Wave
parameters are calculated using Stokes 3^rd Order Wave Theory. The
drag, inertia, and lifting forces that changed during the wave period are determined
by the Morrison Equation. The new loading is performed on the system which is
deformed due to the previous force considering Time History approach. The
critical values of section displacements are calculated by using the Finite
Element Method. The maximum displacements are compared with those determined by
ANSYS-FSI (Fluid Structure Interaction) technique which combines structural
analysis with flow analysis. The concordance of the results of the two analysis
methods indicates that the Finite Element Method can be used to perform an
equivalent dynamic analysis.

Keywords

Hydrodynamic forces, Finite elements method, 3rd order Stokes wave theory

References

• [1] Sarpkaya, T., Rajabi, F. 1980. Hydrodynamic drag on bottom-mounted smooth and rough cylinders in periodic flow. In Offshore Technology Conference. Offshore Technology Conference.
• [2] Lundgren, H., Mathiesen, B., Gravesen, H. 1976. Wave loads on pipelines on the seafloor. In Proc., 1st Int. Conf. on Behaviour of Offshore Struct.(BOSS 76) (Vol. 1, pp. 236-247).
• [3] Sumer, B. M., Jensen, B. L., Fredsøe, J. 1991. Effect of a plane boundary on oscillatory flow around a circular cylinder. Journal of Fluid Mechanics, 225, 271-300.
• [4] Ballet, J. P., Hobbs, R. E. 1992. Asymmetric effects of prop imperfections on the upheaval buckling of pipelines. Thin-Walled Structures, 13(5), 355-373.
• [5] Xiaoyun, G., Fuping, G., Qun, P. 2001. Wave-soil-pipe coupling effect on submarine pipeline on-bottom stability. Acta Mechanica Sinica, 17(1), 86-96.
• [6] Ong, M. C., Utnes, T., Holmedal, L. E., Myrhaug, D., Pettersen, B. 2010. Numerical simulation of flow around a circular cylinder close to a flat seabed at high Reynolds numbers using ak–ε model. Coastal Engineering,57(10), 931-947.
• [7] Draper, S., An, H., Cheng, L., White, D. J., Griffiths, T. 2015. Stability of subsea pipelines during large storms. Phil. Trans. R. Soc. A, 373(2033), 20140106.
• [8] Gökkuş, Ü. 1995. Computer-Aided Design of Submarine Pipelines, Water Science Technology, 233-241.
• [9] Varol, B. Y., Gökkuş, Ü. 2012 Düzenli Dalga Etkisinde ve Asılı Konumda Bulunan Deniz Boru Hattının Tesir Çizgisi Yöntemi Ile Analizi. Celal Bayar Üniversitesi Fen Bilimleri Dergisi, 8(2), 31-42.
• [10] Cokgör, S. Avcı, I. 2001. Hydrodynamic Forces on Partly Buried Tandem Twin Pipelines in Current, Ocean Engineering, 28:1349-1360.
• [11] Lee, M. M. K. 1999. Strength, stress and fracture analyses of offshore tubular joints using finite elements. Journal of Constructional Steel Research, vol. 51, no. 3, pp. 265–286.
• [12] CERC, 2002. Coastal Engineering Manual, Wave Mechanics, PartII, USA, Coastal Engineering Research Center, Vicksburg, MS, USA.
• [13] Ergin, A. 2010. Coastal Engineering, Metu Press, Ankara, Turkey.
• [14] Sorensen R. M. 2005, Basic Coastal Engineering, vol. 10, Springer Science & Business Media, Berlin, Germany.
• [15] Le Mehaute, B. 1976. Similitude in coastal engineering. Journal of the waterways, harbors and coastal engineering division, 102(3), 317-335.
• [16] Goda, Y. 2010. Random seas and design of maritime structures (Vol. 33). World Scientific Publishing Company.
• [17] Keulegan, G. H., Carpenter, L. H. 1956. Forces on cylinders and plates in an oscillating fluid: US Department of Commerce. National Bureau of Standards.
• [18] Yalçın, Y. Çevik, E. 2009. Kıyı Mühendisliği, Beta Basım A.Ş., İstanbul.
• [19] Wang E. Nelson T., 2002. Structural dynamic capabilities of ANSYS,” in Proceedings of the ANSYS 2002 Conference, Pittsburg, PA, USA.
• [20] Benra, F. K., Dohmen, H. J., Pei, J., Schuster, S., Wan, B. 2011. A comparison of one-way and two-way coupling methods for numerical analysis of fluid-structure interactions. Journal of applied mathematics.