Abstract
This study investigated thickness requirements for field fabricated (large) spherical liquefied natural gas (LNG) pressure vessels using the finite element method. In the FEM modeling, 3-dimenisonal analysis was used to determine thickness requirements at different sections of a 5-m radius spherical vessels based on the allowable stress of the material as given in ASME Section II Part D. Shallow triangular element based on shallow shell formation was employed using area coordinate system which had been proved better than the global coordinate system in an earlier work of the authors applied to shop built vessels. This element has five degrees of freedom at each corner node-five of which are the essential external degrees of freedom excluding nodal degree of freedom associated with in plane shell rotation. Set of equations resulting from Finite Element Analysis were solved with computer programme code written in FORTRAN 90 while the thickness requirements of each section of spherical pressure vessels subjected to different loading conditions were determined. The results showed membrane thickness decreasing from the base upwards for LNG vessels but constant thickness for compressed gas vessels. The obtained results were validated using values obtained from ASME Section VIII Part UG. The results showed no significant difference (P > 0.05) with values obtained through ASME Section VIII Part UG.
Highlights
Over the past few decades, world consumption of liquefied natural gas (LNG) has increased more than five-fold and it is predicted that this growth will continue to be very strong
This study investigated thickness requirements for field fabricated spherical liquefied natural gas (LNG) pressure vessels using the finite element method
In the FEM modeling, 3-dimenisonal analysis was used to determine thickness requirements at different sections of a 5-m radius spherical vessels based on the allowable stress of the material as given in ASME Section II Part D
Summary
Over the past few decades, world consumption of LNG has increased more than five-fold and it is predicted that this growth will continue to be very strong. Single-curvature polyhedron hydro-bulging technology is a new technology for manufacturing spherical vessels and it has a good application foreground. This technology has been used in practice, but the designing and manufacturing of polyhedral are based on experiences, and the final quality of spherical vessels cannot be forecast quantitatively. Their work showed that singlecurvature polyhedron hydro-bulging process could be simulated well by the finite element method code. OLUWOLE design and stress modeling in spherical vessels using global and area coordinate systems in the finite element modeling. Construction of shop built spherical [9] and field fabricated cylindrical vessels have being carried out [10], there is still intense interest in the designing of spherical pressure vessels [11,12,13]. The area coordinates system was applied in this modeling
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
