A global mechanical analysis and optimization of vacuum vessel and attached structure of KTX device

KTX (Keda Torus eXperoment) is a new reversed field pinch magnetic confinement device which is designed in University of Science and Technology of China. Its main parameter is between RFX and MST. The vacuum vessel system of KTX is designed to keep plasma in a high vacuum and guarantee the enough mechanical strength to resist stress loads in different working conditions. The main design work has been already completed while the R&D work and preparation for manufacturing and assembling is going on. With the purpose of getting a prediction of the mechanical behavior of KTX vacuum vessel and its supports, electromagnetic and structural finite element models from three different considerations are built. This article presents the calculation methods of mechanical behavior respectively due to the electromagnetic force during plasma disruption, the buckling of elongated support legs and vacuum vessel separating. Furthermore, in accordance with the results, a comprehensive cognition to the relationship between mechanical structure and strength is indicated, so as to complete the detailed and optimization design.