Thermomechanical investigation on divertor supports for fusion experimental reactor: hydraulic experimental results

The Japan Atomic Energy Research Institute has been conducting technology development aimed at the construction of a fusion experimental reactor to follow JT-60 in Japan. The divertor plate facing the plasma is one of the components of the reactor core assembly, since it has to be operated under severe heat and particle loads and high electromagnetic forces. Thus the divertor supports should be designed so as to provide both flexibility for thermal expansion along the divertor cooling tube and mechanical stiffness for sustaining the electromagnetic force during plasma disruption as well as easy replacement in the case of failure. er to meet these requirements, we have developed a new divertor support system based on a sliding mechanism for flexibility and a hydraulic cotter for replacement. The basic feasibility of this concept has been demonstrated through critical element development. Based on the feasibility study, a 1: 1-scale model of the divertor cooling tube test section with sliding mechanism has been fabricated for thermomechanical experiments to characterize the fluid mechanics, flow-induced vibration and flexibility for thermal expansion at various temperature profiles during normal and baking operations. inary experiments on the fluid mechanical characteristics have been conducted as a function of the water velocity and the following results are obtained. 1. e total pressure drop along the whole test section reaches about 0.7 MPa at the rated water velocity of 10 m−1 at 20 °C, which is mostly dominated by swirl tape inserts and several bend sections, as expected by design estimation. ow-induced vibrations are observed at the two overhang bends with smaller curvatures and become significant at a higher water velocity of more than 10 m s−1.