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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.
Beat Sigg
Nuclear Science and Engineering | Volume 57 | Number 4 | August 1975 | Pages 277-291
Technical Paper | doi.org/10.13182/NSE75-A15420
Articles are hosted by Taylor and Francis Online.
A modified truncation of the P1 equations for the treatment of multidimensional time-dependent neutron transport is presented that avoids some inconvenient features of the usual PL· approximation, such as the nonuniqueness of the stationary equations in vacuum and the discontinuity of certain moments at material interfaces. The mathematical properties of the original (PL) and modified (EPL) approximations, together with interface and vacuum boundary conditions, are compared. An approximate solution method for both types of equations is derived from a variational principle, and numerical results are given for time-dependent P1 and EP1 calculations in two-dimensional cylindrical geometry.
