Deniz Boru Hattı Dinamik Davranışının Sonlu Elemanlar Yöntemi İle Analizi

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

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