In order to investigate the effects of a light-element limiter on plasma parameters, aluminum rail limiters interchangeable with Mo rails were installed top, bottom, and outside directions in the ST tokamak. The inside limiter remained a fixed Mo rail. Compared with discharges produced immediately before and after with the usual Mo limiters, the ''aluminum'' discharges showed an increase of T/sub e/ (by factors of 1.4-2 near the center) and of energy confinement (by factors of 2 to 3 in el. energy/power input, depending on time of observation). H/sub 2/ and He discharges showed practically identical effects. In plasma composition, the Mo concentration dropped significantly, but Fe only slightly if at all; the Al concentration was about 3-5 percent (i.e., large compared to the heavier metals), whereas oxygen, about 4 to 8 percent to start with, dropped to insignificance, probably as a result of Al evaporation. The z/sub eff/ from resistivity increased 20-30 percent although the resistance dropped because of the higher T/sub e/. The improved T/sub e/ and energy confinement are thought to be the result of cumulative effects of more favorable radial current and power input distributions rather than direct energy losses by radiation.
Meservey, E. B., Bretz, N., Dimock, D. L., and Hinnov, E. Aluminum limiter experiment in ST tokamak. United States: N. p., 1976.
Web. doi:10.2172/7363005.
Meservey, E. B., Bretz, N., Dimock, D. L., & Hinnov, E. Aluminum limiter experiment in ST tokamak. United States. doi:10.2172/7363005.
Meservey, E. B., Bretz, N., Dimock, D. L., and Hinnov, E. Thu .
"Aluminum limiter experiment in ST tokamak". United States.
doi:10.2172/7363005. https://www.osti.gov/servlets/purl/7363005.
@article{osti_7363005,
title = {Aluminum limiter experiment in ST tokamak},
author = {Meservey, E. B. and Bretz, N. and Dimock, D. L. and Hinnov, E.},
abstractNote = {In order to investigate the effects of a light-element limiter on plasma parameters, aluminum rail limiters interchangeable with Mo rails were installed top, bottom, and outside directions in the ST tokamak. The inside limiter remained a fixed Mo rail. Compared with discharges produced immediately before and after with the usual Mo limiters, the ''aluminum'' discharges showed an increase of T/sub e/ (by factors of 1.4-2 near the center) and of energy confinement (by factors of 2 to 3 in el. energy/power input, depending on time of observation). H/sub 2/ and He discharges showed practically identical effects. In plasma composition, the Mo concentration dropped significantly, but Fe only slightly if at all; the Al concentration was about 3-5 percent (i.e., large compared to the heavier metals), whereas oxygen, about 4 to 8 percent to start with, dropped to insignificance, probably as a result of Al evaporation. The z/sub eff/ from resistivity increased 20-30 percent although the resistance dropped because of the higher T/sub e/. The improved T/sub e/ and energy confinement are thought to be the result of cumulative effects of more favorable radial current and power input distributions rather than direct energy losses by radiation.},
doi = {10.2172/7363005},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jan 01 00:00:00 EST 1976},
month = {Thu Jan 01 00:00:00 EST 1976}
}