Shattered pellet penetration in low and high energy plasmas on DIII-D
Name
20ja047_full.pdf
Size
6.84 MB
Format
Adobe PDF
Checksum (MD5)
3934d28922d90915842d3ea1ede6b4a8
Author(s)
Raman, R.
Sweeney, Ryan
Moyer, R.A.
Eidietis, N.W.
Shiraki, D.
Herfindal, J.L.
Sachdev, J.
Hollmann, E.M.
Jardin, S.C.
Baylor, L.R.
Date Issued
February 2020
Journal
Nuclear Fusion
Publisher
IOP
Abstract
Shattered pellet injection (SPI) has been adopted as the baseline disruption mitigation system for ITER, as the radiative payload penetration into DIII-D plasmas from SPI is superior to those using the massive gas injection (MGI) method. Because of the substantial differences in the energy content of ITER plasma and those in present experiments, reliable 3D MHD modeling, benchmarked against present experiments is needed to project to ITER plasmas. In support of these needs, the depth of SPI fragment penetration in DIII-D plasmas was investigated by injecting SPI into two discharges with vastly different energy content and pedestal height. 400 Torr-L pure Ne fragmented pellets at a velocity of about 200 m s−1 were injected into a 0.2 MJ L-mode discharge and a 2 MJ super H-mode discharge. Results show deep penetration of SPI fragments into low-energy plasmas in DIII-D. SPI fragment penetration is reduced as the plasma energy content increases, with some discharges exhibiting penetration that is confined to the outer regions of the plasma. The injected SPI fragments are also spread out over a distance of about 20 cm, which results in some fragments arriving near the end of or after the thermal quench is over.
Description
Submitted for publication in Nuclear Fusion
MIT Department
Massachusetts Institute of Technology. Plasma Science and Fusion Center
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1088/1741-4326/ab686f
