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Fusion Science and Technology
Latest News
In transition: Commercializing fusion power
Commercial fusion power is closer than ever. There are now around 30 U.S. fusion companies, several of which claim to be on track to connect to the grid as early as the 2030s.
Tokamak and laser inertial confinement approaches benefit from decades of research at facilities such as the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory and ITER, with alternative concepts including stellarator, magnetic mirror, and Z-pinch confinement also making notable progress as private and government funding for fusion increases.
K. V. Subbaiah, A. Natarajan, D. V. Gopinath, K. Takeuchi
Nuclear Science and Engineering | Volume 109 | Number 4 | December 1991 | Pages 373-379
Technical Paper | doi.org/10.13182/NSE91-A23862
Articles are hosted by Taylor and Francis Online.
A seminumerical technique developed for solving the transport equation in slab geometry is adopted for a point isotropic source of gamma rays in spherical geometry. Only Compton scattering is dealt with currently. Two quantities, namely surface flux and surface source, are introduced to circumvent singularities at the origin. A collision-by-collision iterative approach is followed to solve the coupled form of integral transport equations separating the spatial and energy transmission kernels. The spatial transmission kernel for obtaining surface flux from surface source is derived. The energy angle transmission kernels are evaluated by taking recourse to Legendre polynomial expansions. The uncollided and first collision surface fluxes are obtained analytically. An appropriate functional form is chosen for the spatial interpolation of flux and source facilitating large spatial mesh widths. The computer program ASFIT-Sphere is written on the basis of these formulations. Energy flux spectra and angular distributions obtained by the current method of scattered photons 2 and 3 mean-free-paths away from a 137Cs source in water are compared with the data of ANS-6 shielding benchmark experiments. Comparison with calculations by other methods is also included.