Transient shrinkage pressure on the interface of two concentric cylinders

Abstract

The shrinkage pressure due to thermal effects, exerted by a hollow cylinder on a main cylinder, is analysed. The hollow cylinder is preheated and then coupled to a main cylinder. Two cases of preheating are studied, that of uniform preheating and a non-uniform preheating. The variation of the shrinkage pressure in the transient state is discussed. It is shown that for both cases of preheating the maximum shrinkage pressure is reached in the transient state. It can be up to 70 per cent greater than the final steady pressure. The effectiveness of prestressing, for the same thermal conditions, is maximum for the ratio b a = 2·4 in the case of non-uniform preheating, while for uniform preheating, it increases monotonically with b a ( b and a are, respectively, the external and internal radii of the hollow cylinder). Thermal and mechanical properties are assumed equal for hollow and main cylinders.