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Breaking ground on a new approach to construction
The drive to Kairos Power’s reactor demonstration site in Oak Ridge, Tenn., is not only scenic—it’s historic. Nearly 85 years ago, roughly 30,000 construction workers transformed orchards and farmland into a key Manhattan Project site. Depending on your route, you may pass by one of the three gatehouses that were once military checkpoints controlling access to Atomic Energy Commission production facilities.
J. K. Fletcher
Nuclear Science and Engineering | Volume 84 | Number 1 | May 1983 | Pages 33-46
Technical Paper | doi.org/10.13182/NSE83-A17455
Articles are hosted by Taylor and Francis Online.
A solution of the multigroup neutron transport equation in one, two, or three space dimensions is presented. The flux φg(r, Ω) at point r in direction for energy group g takes the form of an expansion in unnormalized spherical harmonics. Thus, where θ and φ are the axial and azimuthal angles of Ω, the associated Legendre polynomials, and N an arbitrary odd number. Using the various recurrence formulas for , a linked set of first-order differential equations in the moments results. Terms with odd 1 are eliminated yielding a second-order system to be solved by two methods. First, a finite difference formulation using an iterative procedure is given, and second, in XYZ and XY geometry, a finite element solution is presented. Results for a test problem using both methods are exhibited and compared.