Structural analysis of a prototype fast shutter for ITER cCXRS diagnostic

Abstract

Abstract-Optical lifetime of the first mirror is a critical issue for the ITER upper-port-plug core-charge-exchange-spectroscopy diagnostic. A fast shutter is engaged to protect the mirror from depositions between measurements. The prototype shutter will be examined in a test vacuum vessel that is now under development in Forschungszentrum Jülich, Germany. Being located near the plasma, the shutter operates under severe thermal and electromagnetic (EM) loads. The multifield analyses conducted for the shutter are presented in this paper. Since the fast shutter can operate within 0.7 s, its static structural analysis should be accompanied by dynamic studies. This paper gives details about the numerical strategy used for a multifield ANSYS modeling of a complex structure. The shutter structural performance under the service, thermal, and EM loadings is in line with the requirements. A solution for a problem of high local thermostresses revealed by the analysis is proposed. Problems connected with other possible port-plug-shutter layouts are discussed.

Status of the R&D activities to the design of an ITER core CXRS diagnostic system

“…For this reason, it was so far one of the mostly studied components [10,11,[16][17][18]. Multi-field (thermal, electromagnetic and structural) analysis for the previous shutter options [10,16] resulted in the baseline design within IC3, a frictionless fast shutter which can be operated at opening and closing speeds compatible with the characteristic times of the DNB modulation. Reaction times (full opening or closing) below 0.7 s are expected.…”

Strategies of Numerical Modeling in Component Development for Fusion Devices

“…This express approach [13], [14] can deal with the multifield models that are meshed with sufficient accuracy in regions of high field gradient (for all types of analysis). Boundary conditions for the EM analysis are taken from a global EM model, which features only massive structures in a simplified way, and these conditions are applied to the outer boundaries of all components of the detailed model.…”