Towards a unified design-by-analysis solution to pressure vessel nozzle-shell junctions under combined loading

The finite element method is the most commonly used modern 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, oblique nozzles combinations, fillet weld applications, pad reinforcements, stress linearization, external loading cases, limit loads, and cyclic loads. In addition, elastic, elastic - perfectly plastic, full plastic and fracture analysis were performed.Stress intensity factors are obtained with the results of finite element analysis for various internal pressure and external loading conditions, and an attachment parameter and design curves are proposed. Finally, the Multiple Plastic Slope method, which is an alternative to TI and TES methods, which can be applied more practically and can make a more conservative plastic limit load estimation, has been proposed.

Name dc:type.qualificationname

phd

Level dc:type.qualificationlevel

doctoral-pg

Grantor dc:publisher.institution

University of Strathclyde

Year dc:date.issued

2022

Author dc:creator

• Bozkurt, Murat

Advisor dc:contributor.advisor

• Nash, David

DOI

10.48730/f85m-ee53

Identifier

T16193

Author Identifier

201756273

OAI identifier oai:identifier

oai:strathclyde:0c483j92t