Session: DA-01-02 Design and Analysis of Pressure Vessels and Components-2

Paper Number: 121933

121933 - Research on Stress and Displacement Distribution of Obround Shell 

Using the closed-form solution of obround shell, theoretical analyses of stress and displacement of obround shells are performed. With the flattened shell introduced, the maximum stresses and displacement of obround shells increase significantly. The length of flat shell is the key factor to influence the maximum stress location and value. For obround shells, the maximum stress is the function of two defined dimensionless geometrical parameters. The results of parameter studies show that for most engineering applications, the maximum stress occurs at the middle section of curved segment instead of the flat portion. For the cylindrical shells, stress increment due to out-of-roundness is studied. The ovalized cylindrical shell is treated as an elliptical shell. Therefore, the maximum stress of an elliptical shell can be estimated using the results of a virtual obround shell. The results of stress analysis for ovalized cylindrical shell are compared to the results of FEA. The results show that even within the range of out-of-roundness value accepted by the codes, the stress increment due to ovalize is still considerable, especially for thin to moderate wall shells. Since the out-of-roundness is inevitable in engineering application, the stress increase should not be ignored. The minimum required wall thickness estimated by the current codes may be underestimated.

Presenting Author: Yao Jin Propak systems Ltd.

Presenting Author Biography: Jin Yao, Ph. D., graduated from the Department of Mechanical Engineering of Southwest Jiaotong University. Worked at a Chinese university for 15 years. Research areas were fatigue, creep, stress analysis, damage, fracture and so on. Worked for EPC companies in Canadian oil and gas industry for more than 17 years. The scope of work includes design and analysis of vessel and pipe lines, CFD analysis, research and development, torsional vibration analysis, structure design and so on.

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