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Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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Securing the advanced reactor fleet
Physical protection accounts for a significant portion of a nuclear power plant’s operational costs. As the U.S. moves toward smaller and safer advanced reactors, similar protection strategies could prove cost prohibitive. For tomorrow’s small modular reactors and microreactors, security costs must remain appropriate to the size of the reactor for economical operation.
A. D. Caldeira, A. F. Dias, R. D. M. Garcia
Nuclear Science and Engineering | Volume 130 | Number 1 | September 1998 | Pages 70-78
Technical Paper | doi.org/10.13182/NSE98-A1990
Articles are hosted by Taylor and Francis Online.
A degeneracy that may occur in the PN solution to the multigroup slowing-down problem reported in part I of this work is studied. The considered degeneracy is of first order, i.e., it connects only two groups in the defined multigroup structure. The singularities caused by the higher-energy group in the particular solution for the lower-energy group are removed by (a) adding to this solution convenient multiples of the PN modes that define the homogeneous solution for the lower-energy group and (b) applying a limiting procedure to the resulting expression. The propagation of the degenerate solutions to other groups below the lower-energy group is also studied. A test problem posed some years ago in the context of the FN method is solved to demonstrate the consistency of the developed degenerate solutions. Numerical results are tabulated for several orders of the approximation and are compared with previously reported FN results.