THERMOMECHANICAL INTERACTION OF PARTICLE BED-STRUCTURAL WALL IN A LAYERED CONFIGURATION .2. COMBINED EFFECTS OF BED THERMAL EXPANSIONS AND COOLANT PRESSURE

In Part I of this study, a model representing the thermomechanical res ponse of a particle bed-structural wall system in a layered configurat ion, subjected to both a bed temperature rise and an external coolant pressure, was presented. The results of a parametric study, based on t he developed model, on the effect of the bed thermal expansions alone on a beryllium particle bed-stainless steel system were also presented . In this paper we present Part II of the study. The thermomechanical behaviour of a beryllium particle bed-stainless steel structural wall system subjected to (1) pure external coolant pressure and (2) a combi nation of bed temperture rise and coolant pressure is considered. Long itudinal variations in the thermomechanical properties of the particle bed-structural wall are studied. Results show that the bed temperture rises in the range 100-400 degrees C and coolant pressures in the ran ge 1-2 MPa, depending on the stiffness of the structural walls, could cause non-uniform effective thermal properties through the particle be d and increase the bed effective thermal conductivity by a factor of 2 -5 and the bed-wall interface thermal conductance coefficient by even larger factors. The effect of increased wall stiffness is to reduce th e influence of the external coolant pressure and to increase the influ ence of thermal expansions on the particle bed thermomechanical respon se.