A comparison of stress analysis and limit analysis approaches for single and multiple nozzle combinations in cylindrical pressure vessels. (15th December 2021)

• Record Type: Journal Article
• Authors: Bozkurt, Murat; Nash, David; Uzzaman, Asraf
• Is Part Of: International journal of pressure vessels and piping. Volume 194:Part B(2021)
• Publication Date: 2021-12-15
• Subjects: Pressure vessel -- Nozzle -- FEM -- Limit load -- External load; Pressure vessels -- Periodicals; Pipe -- Periodicals; Récipients sous pression -- Périodiques; Tuyaux -- Périodiques; Pipe; Pressure vessels; Periodicals; 681.76041
• DOI: 10.1016/j.ijpvp.2021.104563
• Languages: English
• ISSNs: 0308-0161

Abstract

Abstract: The finite element method is the most commonly used approach when solving complex practical cylinder-cylinder junctions in pressure vessels. This is used when the geometrical arrangement is out with the permitted scope of the design-by-rule approaches or when detailed stress information is required as in a fatigue assessment. High-stress concentrations occur on the crotch corner for cylinder-cylinder joints, and it is possible to reach solutions for this problem by using both theoretical and numerical solutions. However, those approaches do not fully overlap nor have the same underlying assumptions. As such, an innovative high-fidelity finite element model has been developed to provide a holistic unified approach which can tackle a wide range of problems. In this study, various detailed nozzle design challenges were investigated including single and multiple nozzle combinations, nozzle-cylinder systems with different size ratios, fillet weld applications, limit loads and external loading cases were analyzed. The results obtained are compared with well-respected calculation methods such as WRC537, and a new approach is presented for the analysis of cylinder-cylinder combinations. Highlights: The validated high-fidelity model for cylinder-cylinder intersection problems has been made more comprehensive. The key load variables have been examined and their influences quantified. Stress analysis and limit load calculations have been completed The effect of the internal crotch corner fillet on the stress values is more effective than the external fillet effect. For nozzle groups, the stresses decrease with the increase in ligament distance