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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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High temperature fission chambers engineered for AMR/SMR safety and performance
As the global energy landscape shifts towards safer, smaller, and more flexible nuclear power, Small Modular Reactors (SMRs) and Gen. IV* technologies are at the forefront of innovation. These advanced designs pose new challenges in size, efficiency, and operating environment that traditional instrumentation and control solutions aren’t always designed to handle.
Ricardo C. De Barros, Edward W. Larsen
Nuclear Science and Engineering | Volume 111 | Number 1 | May 1992 | Pages 34-45
Technical Paper | doi.org/10.13182/NSE92-A23921
Articles are hosted by Taylor and Francis Online.
A new nodal method is developed for the solution of one-group discrete ordinates (SN) problems with linearly anisotropic scattering in x,y-geometry. In this method, the “spectral Green’s function” (SGF) scheme, originally developed for solving SN problems in slab geometry with no spatial truncation error, is generalized to solve the one-dimensional transverse-integrated SN nodal equations with the “constant” approximation for the transverse leakage terms. The resulting “SGF-constant nodal” (SGF-CN) method is more accurate than conventional coarse-mesh methods for deep penetration problems because it treats the scattering source terms implicitly and exactly; the only approximation involves the transverse leakage terms. In conventional SN nodal methods, the transverse leakage terms and scattering source are both approximated. We solve the SGF-CN equations using the one-node block inversion iterative scheme, which uses the best available estimates for the node-entering fluxes to evaluate the node-exiting fluxes in the directions that constitute the incoming fluxes for the adjacent nodes as the equations are swept across the system. Finally, we give numerical results that illustrate the accuracy of the SGF-CN method for coarse-mesh calculations.