Development of thermal transient stress charts for screening evaluation of thermal loads

Furuhashi, Ichiro*; Kasahara, Naoto; Shibamoto, Hiroshi

Thermal transient stress charts were developed for screening evaluation of thermal loads. Summay of obtaned results are as follows. (1) Thermal stress was theoretically analyzed on the plate subjected to thermal transient on both surfaces, and the design charts were proposed for evaluation of thermal transient stress. Compared with conventional design charts for the plate under single surface heat transfer, their applicable area is further extended. (2) Developed design charts can predict temperature and stresses responses to step or ramp change of fluid temperature. Utilizing these charts, surface temperature, average temperature in thickness, surface stress, bending stress and peak stress at arbitrary time can be obtained. (3) Non-dimensional temperature and stress were introduced, and reading errors can be reduced compared with the conventional ones. (4) Design charts were also proposed on the maximum thermal stresses and their arising times. It was revealed that the maximum thermal stresses never exceed 2 times of steady-state stress under the fixed back surface temperature. (5)Green functions of transient temperature and thermal stresses were developed. Temperature and thermal stresses can be predicted within 1.4% error. These charts will contribute to the screening evaluation of thermal loads with their locations, and will be employed for sensitive analyses for design and understanding of thermal stress mechanisms.