Abstract
An array of fixed Langmuir probes spanning the inner and outer divertor strike points has been used to measure the electron temperature, plasma density, and particle/heat flux profiles of the divertor plasma in DIII-D. We report here on observations made during the steady state phase of high-power neutral-beam heated H-mode plasmas. These data are important for predicting the expected impurity sources and target plate material lifetimes in future high power tokamaks such as ITER. H-mode plasmas formed with a high divertor neutral pressure in the absence of external gas feed in DIII-D were found to have beneficial consequences in reducing the peak values of divertor electron temperature without loss of core energy confinement. We have observed a steady state, high density (npl,d≈1014 cm-3), moderate temperature (<50 eV) divertor plasma in DIII-D at divertor power levels of 3 MW/m2. A better understanding of the importance of collisional effects may be needed to interpret these results.
| Original language | English |
|---|---|
| Pages (from-to) | 133-138 |
| Number of pages | 6 |
| Journal | Journal of Nuclear Materials |
| Volume | 196-198 |
| Issue number | C |
| DOIs | |
| State | Published - Dec 1 1992 |
Funding
The authors would like to acknowledge our appreciation of Dr. T.C. Simonen, Dr. R.D. Stambaugh and the General Atomics staff for making this work possible. This project would also not have been possible without the technical assistance of J.A. Whaley and J. Smith. This work was supported by US DOE contract no. DE-AC04-76-DP-00789, W-7405-ENG-48, DE-AC03-89ER51114, and DE-AC05-84OR21400.
