High heat flux interactions and tritium removal from plasma facing components by a scanning laser

C.H. Skinner1, C.A. Gentile1, A. Hassanein1,2
1Princeton Plasma Physics Laboratory, Princeton, NJ, USA
2Argonne National Laboratory, Argonne, IL, USA

Tóm tắt

A new technique for studying high heat flux interactions with plasma facing components is presented. The beam from a continuous wave 300 W neodymium laser was focussed to 80 W/mm/sup 2/ and scanned at high speed over the surface of carbon tiles. These tiles were previously used in the TFTR inner limiter and have a surface layer of amorphous hydrogenated carbon that was codeposited during plasma operations. Laser scanning released up to 84% of the codeposited tritium. The temperature rise of the codeposit on the tiles was significantly higher than that of the manufactured material. In one experiment, the codeposit surface temperature rose to 1,770/spl deg/C while for the same conditions, the manufactured surface increased to only 1,080/spl deg/C. The peak temperature did not follow the usual square-root dependence on heat pulse duration.

Từ khóa

#Plasma temperature #Tiles #Plasma waves #Manufacturing #Laser beams #Neodymium #Surface waves #Surface emitting lasers #Amorphous materials #Plasma materials processing

Tài liệu tham khảo

10.1016/S0022-3115(06)80109-1 10.1016/S0022-3115(00)00663-2 10.1016/S0022-3115(01)00679-1 10.1016/S0022-3115(98)00586-8 eckstein, 1996, Physical Sputtering and Radiation-Enhanced Sublimation, Physical Processes of the Interaction of Fusion Plasmas with Solids, 93 carslaw, 1959, Conduction of Heat in Solids, 75 0, CRC Handbook of Chemistry and Physics brooks, 1992, FDR report 10.1016/0022-3115(89)90292-4 smolik, 1990, Evaluation of graphite/steam interactions for ITER, Idaho National Laboratory report 10.1016/S0022-3115(98)00586-8 10.1007/978-1-4419-8696-2_51 10.1016/S0022-3115(01)00679-1 skinner, 0, Long term tritium trapping in TFTR and JET, Proceedings of the 28th EPS Conference on Controlled Fusion and Plasma Physics 10.1016/S0022-3115(02)00713-4 skinner, 1997, Tritium removal by CO, laser heating, Proc 17th IEEE/NPSS Symp Fusion Eng San Diego CA, 1, 321, 10.1109/FUSION.1997.687047 10.1016/S0022-3115(99)00052-5 skinner, 0, Tritium removal by laser heating and its application to tokarnaks, Proceedings of the 6th International Conference on Tritium Science and Technology 10.1088/0029-5515/41/12/218 10.1016/0022-3115(94)00619-9 10.1109/FUSION.2002.1027701 paffett, 2002, Surface Characterization of TFTR First Wall Graphite tiles used during DT operations, Fusion Science and Technology, 10.13182/FST02-A22722 10.1016/0022-3115(89)90394-2 linke, 1990, Disruption simulation experiments in electron and laser beam facilities, Fusion Technol, 428 hassanein, 1999, Physics of collisionless scrape-off-layer plasma during normal and off-normal tokamak operating conditions, Argonne Natlonal Laboratory Report ANL/FPP/TM-296 10.1016/S0022-3115(96)00015-3 10.1016/S0022-3115(96)00213-9 10.1088/0029-5515/31/10/001