Electromagnetic dynamic response of HL-2M vacuum vessel under plasma disruption considering the electromagneto-mechanical coupling effect

Abstract

During plasma disruptions (PDs), transient eddy currents are induced in the HL-2M vacuum vessel (VV) which is a D-shaped, double thin-wall structure. Under the circumstance of high magnetic field, the resulting electromagnetic (EM) forces during PDs are large and the dynamic response of related structures may be violent. In this complicated EM circumstance, the EM-mechanical coupling effect may also have a great influence on the dynamic response of VV structure. In this paper, the EM field and structural dynamic response of HL-2M VV during PDs are simulated by adopting a numerical code of the Lagrangian approach. The Lagrangian approach is on the basis of the Maxwell equations in the Lagrangian description, which treats the coupling behavior of magnetic damping effect without explicitly using the velocity term. This approach can be easily applied to actual structures by updating FEM meshes and reforming coefficient matrices before calculating EM field at each time step. In this work, the disruption plasma currents of operating conditions are simulated by using the DINA code and then the dynamic responses of displacements and stresses of the VV of HL-2M are obtained for both cases with and without considering the coupling effect. The numerical results show that stresses under the disruptions (MD and VDE) are not significant and the coupling effect does not significantly affect the peak dynamic response for the HL-2M problem.

Influence of shielding plates on dynamical response of HL-2M vacuum vessel due to electromagnetic force during a plasma disruption

“…moving the coordinate scheme proposed by authors (Li et al, 2014a(Li et al, , 2014b. The moving coordinate scheme has been successfully applied to the dynamical analyses of VV in the Tokamak device (Dong et al, 2016;Yuan et al, 2016). However, the influence of SPs on the dynamical response of the HL-2M VV has not been considered yet, which is important for the design of both the SPs and the VV.…”