ESTIMATE OF ERRORS IN APPROXIMATE TEMPERATURE AND THERMAL-STRESS CALCULATIONS.
COLUMBIA UNIV NEW YORK INST OF FLIGHT STRUCTURES
Pagination or Media Count:
After a general discussion of the estimate of errors in calculation of temperature and thermal stresses, a general theorem and a method for the construction of upper and lower bounds for the solution of three-dimensional heat-conduction problems is presented. Emphasis is placed on cases of moving boundaries, thus including problems of change of phase. Errors in stress calculations proper are then studied, with attention given to the fact that special difficulties are created by the existence of temperatures which cause zero stress. Elastic beams and plates are analyzed, and it is found that the maximum stress cannot exceed the quantity 43 alpha ET where T is the maximum difference in temperature in the body and the relevance of this fact in error estimates is noted. Simplifications for symmetrical and antisymmetrical temperature distributions are given. Elastic-perfectly plastic beams and plates are examined in the last section of the paper. Author