R.J. Cerbone and E.T. Cheng ,
TSI Research, Inc., 225 Stevens Ave. Solana Beach, CA 92075
Y-K. M. Peng,**
Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, NJ 08543
A fusion plasma based volumetric neutron source (VNS) concept has been developed in recent studies as a possible intermediate step to develop the necessary technology for reactor components of future fusion power plants. Such a VNS would complement ITER in testing, developing, and qualifying nuclear technology components.
A recently developed design concept for a spherical torus based VNS permits the development of capability for increasing fusion power and wall loading. In this paper, we report the results of neutronics calculations for such a ST-VNS with neutron wall loading ranging from 0.5 to 5 MW/m2. Analyses have been performed for several designs to determine the sensitivity of the system performance to variations in aspect ratio, elongation and fusion power.
The calculations were performed with the two-dimensional discrete ordinates neutron and photon transport code, TWODANT, developed at Los Alamos. The nuclear data library employed is the FENDL-1 based, multi-group neutron (175 groups) and gamma-ray (42 groups) coupled transport library. Detailed results include two-dimensional neutron flux contours, nuclear heating, dpa and spatially dependent neutron spectra for activation analyses.
Power reactor relevant blankets were used for the test modules in ST-VNS to determine how the test environment would scale to such a demonstration fusion power reactor (DEMO). The results show that, given identical neutron wall loading, the ST-VNS provides DEMO-like neutron flux and nuclear heating profiles, lending confidence to the reactor prototypicality of the ST-VNS.
Neutronics calculations were also carried out for the blanket and divertor materials presently assumed in ITER engineering design. The results indicate that the ST-VNS can simulate for the test modules ITER-like neutron wall loading, nuclear heating, and neutron fluxes. The neutronics environment was also calculated for the divertor region for comparison of activation with the divertor concept used in the ITER design.
* Work supported by U.S. Department of Energy, Small Business Innovative Research Grant No. DE-FG03-95ER82098.
**On assignment from Oak Ridge National Laboratory, P.O. Box 2009, Oak Ridge, TN 37831