Injection of hydrogen macroparticles into T-10 tokamak
Abstract
Initial experiments on the injection of hydrogen pellets with characteristic dimension d = h = 1.3 mm and velocity V sub p similar to or less than 0.7 km s sup-1 into the deuterium plasma of a T-10 tokamak are described. The interaction between the macroparticles and the tokamak plasma is investigated for a wide range of plasma parameters: B = 1.5 - 3 T, I sub p = 210 - 500 kA, T sub e(0) = 0.6 - 1 keV, N sub e = (1.5 - 6) 10 to the 13th power cu. cm. The typical evaporation rate is found as a function of the small radius, and the variation in the average density along one of the center chords caused by macroparticle injection is analyzed. It is found that the injection of macroparticles increases the maximum concentration corresponding to stable discharge combustion by 20 to 50 percent. Injection initiated cutoff only for near critical plasma densities. No degradation in stability was observed as q was reduced from 4 to 2. Comparison with the analytical data shows that evaporation occurs more rapidly than the model predicts, possibly because the model employed an approximation of the monoenergetic electron stream.
- Publication:
-
USSR Rept Phys Math JPRS UPM
- Pub Date:
- June 1985
- Bibcode:
- 1985RpPhM.......65A
- Keywords:
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- Beam Injection;
- Hydrogen Plasma;
- Particle Beams;
- Tokamak Devices;
- Deuterium;
- Evaporation Rate;
- High Energy Interactions;
- Pellets;
- Plasma Density;
- Plasma Physics