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NRC looks to leverage previous approvals for large LWRs
During this time of resurging interest in nuclear power, many conversations have centered on one fundamental problem: Electricity is needed now, but nuclear projects (in recent decades) have taken many years to get permitted and built.
In the past few years, a bevy of new strategies have been pursued to fix this problem. Workforce programs that seek to laterally transition skilled people from other industries, plans to reuse the transmission infrastructure at shuttered coal sites, efforts to restart plants like Palisades or Duane Arnold, new reactor designs that build on the legacy of research done in the early days of atomic power—all of these plans share a common throughline: leveraging work already done instead of starting over from square one to get new plants designed and built.
Riccardo A. Bonalumi
Nuclear Science and Engineering | Volume 77 | Number 2 | February 1981 | Pages 219-229
Technical Note | doi.org/10.13182/NSE81-A21355
Articles are hosted by Taylor and Francis Online.
An explicit, analytical calculation of homogenized cell parameters has been developed for centrally symmetric cells or supercells. For every principal direction, a set of one-directional (noneigenvalue) calculations driven by neutrons injected from outside generate transmission/reflection matrices from which diffusion coefficient and cross-section matrices, generally full, are obtained analytically. The analytical calculation of the homogenized parameters is carried through for two different angular distributions of the injected neutrons (generic, P1) and for two mesh structures (ultrafine, 1 mesh/cell). Reaction-rate matching cross-section matrices are also obtained and are shown to be related to the conventional edge-flux normalized cross sections. Two test problems, covering both heavy water and light water lattices, show the superiority of the homogenized diffusion theory (HDT) parameters over the traditional ones: In the light water lattice problem, the HDT constants perform even better than analogous constants generated by other authors.
