Although the theory of thermoelasticity has a long history, its foun-
dations having been laid in the first half of the nineteenth century by
Duhamel and Neumann, wide-spread interest in this field did not develop
until the years subsequent to World War Two. There are good reasons for
this sudden and continuing revival of interest. First, in the field of
aeronautics, the high velocities of modern aircraft have been found to
give rise to aerodynamic heating; in turn, this produces intense thermal
stresses and, by lowering the elastic limit, reduces the strength of the
aircraft structure. Secondly, in the nuclear field, the extremely high
temperatures and temperature gradients originating in nuclear reactors
influence their design and operation. Likewise, in the technology of
modern propulsive systems, such as jet and rocket engines, the high
temperatures associated with combustion processes are the origin of
unwelcome thermal stresses. Similar phenomena are encountered in the
technologies of space vehicles and missiles, in the mechanics of large
steam turbines, and even in shipbuilding, where, strangely enough. ship
fractures are often attributed to thermal stres- ses of moderate
intensities. The investigations of these, and similar, problems have
brol!ght forth a remarkable number of research papers, both theoretical
and experimental, in which various aspects of thermal stresses in
engineering structures are described.