Dynamic analysis of the BPX machine structure

A preliminary analysis of the response of the BPX (Burning Plasma Experiment) machine structure to a seismic input was performed. MSC/NASTRAN, a general-purpose finite element computer code, was used. The purpose of this analysis was to assess the probable range of seismically induced stresses and deflections in the machine substructure which connects the machine to the test cell floor, with particular emphasis on the shear pins which will be used to attach the TF (toroidal field) coil modules to the machine substructure. The model consists of beams and plates which represent the mass and stiffness of the various components of the machine structure. These include the TF coils, PF (poloidal field) ring coils, PF solenoid, vacuum vessel, and machine substructure. The results of the current analysis indicate stresses in all load-bearing structural components fall well within the elastic limit (and below the machine design allowables) and the structure should not sustain any significant damage during a safe shutdown earthquake event. >