The study of thermal stresses on pressure vessels has a great signific
ance from the theoretical and practical point of view due to their imp
ortance in many applications. This paper presents a complete analysis
of thermal stresses within a thick-walled cylinder under dynamic inter
nal temperature gradient. A complete evaluation of temperature and str
ess distributions, in a non-steady state, is obtained using a numerica
l model. In this model the temperature of the inside surface of the th
ick-walled cylinder is considered to change according to certain bound
ary conditions. The harmonic and periodic loading conditions are also
studied.