This work presents numerical analyses of transient temperature and thermally-induced stress distributions in a hollow steel sphere heated by a moving uniform heat source applied on a certain zenithal segment (the heated zenithal segment, Theta(H)) of its outer surface (the processed surface) under stagnant ambient conditions. Along the process, themoving heat source (MHS) moves angularly from the first zenithal segment to the last zenithal segment on the processed surface with a constant angular speed, omega, and then returns backward to the first zenithal segment with the same speed. It is assumed that the inner surface is heat-isolated and that the outer surface except the heated segment is under stagnant ambient conditions. The numerical calculations are performed individually for a wide range of thermal conductivity, lambda, of steel and for the different Theta(H)s. The maximum effective thermal stress ratio calculated as per the heat flux intensity (q(0)) can be reduced in considerable amounts. By increasing lambda(similar to 75%) and omega(similar to 63%) the maximum effective thermal stress ratio calculated can be significantly reduced.
This work presents numerical analyses of transient temperature and
thermally-induced stress distributions in a hollow steel sphere heated by a moving
uniform heat source applied on a certain zenithal segment (the heated zenithal
segment, H ) of its outer surface (the processed surface) under stagnant ambient
conditions. Along the process, themoving heat source (MHS)moves angularly from
the first zenithal segment to the last zenithal segment on the processed surface with
a constant angular speed, ?, and then returns backward to the first zenithal segment
with the same speed. It is assumed that the inner surface is heat-isolated and that
the outer surface except the heated segment is under stagnant ambient conditions.
The numerical calculations are performed individually for a wide range of thermal
conductivity, ?, of steel and for the different H s. The maximum effective thermal
stress ratio calculated as per the heat flux intensity (q0) can be reduced in considerable
amounts. By increasing ?(~ 75%) and ?(~ 63%) the maximum effective
thermal stress ratio calculated can be significantly reduced.
