Calculation and prediction of divertor detachment via impurity seeding by using one-dimensional model

Abstract

Abstract Achieving the detachment of divertor can help to alleviate excessive heat load and sputtering problems on the target plates, thereby extending the lifetime of divertor components for fusion devices. In order to provide a fast but relatively reliable prediction of plasma parameters along the flux tube for future device design, a one-dimensional (1D) modeling code for the operating point of impurity seeded detached divertor is developed based on Python language, which is a fluid model based on previous work (Plasma Phys. Control. Fusion 58 045013 (2016)). The experimental observation of the onset of divertor detachment by neon (Ne) and argon (Ar) seeding in EAST is well reproduced by using the 1D modeling code. The comparison between the 1D modeling and two-dimensional (2D) simulation by the SOLPS-ITER code for CFETR detachment operation with Ne and Ar seeding also shows that they are in good agreement. We also predict the radiative power loss and corresponding impurity concentration requirement for achieving divertor detachment via different impurity seeding under high heating power conditions in EAST and CFETR phase II by using the 1D model. Based on the predictions, the optimized parameter space for divertor detachment operation on EAST and CFETR is also determined. Such a simple but reliable 1D model can provide a reasonable parameter input for a detailed and accurate analysis by 2D or three-dimensional (3D) modeling tools through rapid parameter scanning.