| Long circular holes are widely used in biological,chemical,pharmaceutical,experimental,and other fields.Because the stress concentration caused by long circular holes is more serious than that caused by circular holes,the stress analysis,reinforcement design,and mirror structure optimization of long circular holes are particularly important for ensuring the safety of equipment.In this paper,based on the basic parameters related to the oblong opening of a cylindrical container,such as the diameter of the cylinder D,the ratio of the short axis to the diameter of the cylinder b/D,the ratio of the long axis to the short axis of the oblong hole a/b,the flange width B,and the flange height H,a three-dimensional linear elastic finite element numerical analysis method is used to comprehensively study the stress distribution law of the opening and the periphery of the opening,The accuracy of the finite element numerical simulation was verified by using resistance strain measurement;according to the relevant requirements of GB150-2011 and JB4732-1995,analyze and compare the differences in the existing reinforcement methods for cylindrical vessels with oblong openings,and determine the stress classification method as the most suitable reinforcement method based on the reinforcement margin index;using a combination of theoretical analysis and numerical simulation methods,the influence of the dimensions of the long mirror hole and flange reinforcement structure on the stress concentration caused by the opening was determined,and a significant analysis of the factors affecting the stress distribution was conducted.The results showed that the stress concentration coefficient K increased with the increase of a/b and b/D,and decreased with the increase of B and H,with a/b having the most significant impact on K,and b/D and H having the same impact on K,however,it is significantly lower than a/b,and B and D have the lowest impact on K;using numerical simulation and theoretical analysis methods,the stress analysis of the effective reinforcement width and height range of flange reinforced structures is carried out,and the calculation formulas for the effective reinforcement width and height range are obtained;using the method of combining numerical simulation and formula fitting,using MATLAB software,an empirical formula for calculating the maximum stress concentration of the long mirror hole was obtained,and verified using multiple sets of data.Based on the finite element analysis,this paper uses theoretical analysis,numerical simulation to obtain the effective reinforcement range and empirical formulas for calculating the maximum stress concentration of the cylindrical container’s oblong mirror hole flange reinforcement.This has certain significance for improving the design efficiency of the cylindrical container’s oblong opening reinforcement structure. |
PDF Full Text Request