Numerical Design Method for Thermally Loaded Plate-Cylinder Intersections

The present paper is an extension of work on stresses in corner radii already described by the authors in previously published references [1 and 2]. Whereas the original study concerned itself with pressure effects only and the second reference gave the initial version of the work dealing with thermal effects, the report included here gives more recent results concerning specifically thermal loads. As before, the results are limited to inside corner radii between cylinders and flat heat closures. Similarly, the analysis is based on a systematic series of finite element calculations with the significant parameters covering the field of useful design boundaries. The 334 elements containing some 1800 degrees of freedom ensure a realistic determination of local stresses and a large number of complete solutions enables the presentation of smooth design curves. The results are condensed into a rapid method for the determination of peak stresses needed for performing fatigue analysis in pressure vessels subjected to a significant, variable thermal load. The paper takes into account the influence of the film coefficient, temporal temperature variations, and material properties. A set of coefficients provides a convenient method of stress evaluation suitable for design purposes.