2005年2月
Simulation study on influence of chemically eroded carbon impurity transport on net sputtering erosion of carbon materials exposed to edge fusion plasmas
JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS
- 巻
- 44
- 号
- 2
- 開始ページ
- 1069
- 終了ページ
- 1075
- 記述言語
- 英語
- 掲載種別
- DOI
- 10.1143/JJAP.44.1069
- 出版者・発行元
- JAPAN SOC APPLIED PHYSICS
Regarding TEXTOR and ITER-FEAT fusion devices, the net sputtering erosion rate of C targets exposed to their edge fusion plasmas has been investigated using a simulation code for plasma surface interactions, EDDY. The influence of the transport of chemically eroded CD(4) molecules on the net erosion rate is presented. Emphasis is put on the difference in the simulated results between the CD(4) reaction chain with e(-), the CD(+) reaction chain with e- plus D(+), and the sticking coefficients of CD(4) locally returned back to the targets, which are related closely to the local redeposition, for a variety of plasma densities and temperatures. In particular, at a high density such as 10(19) m(-3) and low temperatures of less than 10 eV, the net erosion rate is found to be suppressed by a significant contribution of the local redeposition resulting from the charge exchange reactions of CD(x). with D(+) if all the locally returned CD, radicals stick. For the ITER-FEAT divertor plasma, the profile of the net erosion rate along the outer vertical target is significantly changed by the C impurity concentration in the plasma, which is eroded from other wall surfaces and then transported by the plasma. For the D+ plasma exposure only, the net erosion rate is highest around the separatrix strike point. On the other hand, it is highest at the private plasma region if a few percent of the C impurity concentration is added to the D+ plasma exposure. The local redeposition resulting from the charge exchange reactions significantly suppresses the net erosion rates at these plasma regions, but does not bring about a significant change in the erosion/deposition profile along the outer vertical target.
- リンク情報
- ID情報
-
- DOI : 10.1143/JJAP.44.1069
- ISSN : 0021-4922
- Web of Science ID : WOS:000227675300059