Design-Focused Stress Analysis of Cylindrical Pressure Vessels Intersected by Small-Diameter Nozzles

Abstract

In a related work previously carried out by the authors, finite element analysis of cylindrical vessel–cylindrical nozzle juncture based on the use of thin shell theory, due to the fact that the intersecting nozzle sizes are moderate to large, have been presented. Such analysis becomes invalid in cases when the nozzles are small in sizes which may result in nozzles whose configuration violates the validity of shell assumption. As a result, use of solid elements (based on theory of elasticity) in modeling the cylindrical vessels with small-diameter nozzles is presented in the present paper. Discussions of the numerical experiments and the results achieved are, first, given. The results are then compared with the prediction by other models reported in the literature. In order to arrive at the overall design charts that cover all the possible ranges of nozzle-to-vessel diameter ratio, the charts for the vessels with moderate-to-large-diameter nozzles are augmented with those of cylindrical vessels intersected by small-diameter nozzles developed in this work.