The two-dimensional edge plasma code SOLPS-ITER have been used to study the hydrogen isotope effect on the divertor detachment onset for hydrogen (H), deuterium (D), and tritium (T) based on EAST plasma conditions. Results prove that H with a lighter mass has a stronger ability to penetrate into the core plasma than D and T, resulting in a higher density in the core and a lower density in the SOL. If the line-averaged electron density is selected to characterize the detachment onset, the hydrogen isotope effect is strongly dependent on the measurement chord location which determines the contribution of the core electron density to the line-averaged electron density. The modeling results can explain previous hydrogen isotope experimental results in JET. The drifts effect on hydrogen isotope distributions has also been investigated. As the drifts are taken into account, the relative difference of detachment onset at the outer target becomes larger, while it becomes smaller for the inner target. The drifts show a greater impact on the T ion distribution than D and H ions.
This paper investigates the impact of different hydrogen isotopes (H, D, T) on divertor detachment in the EAST tokamak. The study uses the SOLPS-ITER code to model the plasma behavior and shows that lighter isotopes like H have a stronger ability to penetrate the core, leading to different detachment characteristics. The findings can help explain previous experimental results and inform fusion research on managing divertor detachment.