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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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World Bank, IAEA partner to fund nuclear energy
The World Bank and the International Atomic Energy Agency signed an agreement last week to cooperate on the construction and financing of advanced nuclear projects in developing countries, marking the first partnership since the bank ended its ban on funding for nuclear energy projects.
Farzad Rahnema, Steven Douglass, Benoit Forget
Nuclear Science and Engineering | Volume 160 | Number 1 | September 2008 | Pages 41-58
Technical Paper | doi.org/10.13182/NSE160-41
Articles are hosted by Taylor and Francis Online.
A generalization of multigroup energy condensation theory has been developed. The new method generates a solution within the few-group framework that exhibits the energy spectrum characteristic of a many-group transport solution, without the computational time usually associated with such solutions. This is accomplished by expanding the energy dependence of the angular flux in a set of general orthogonal functions. The expansion leads to a set of equations for the angular flux moments in the few-group framework. The zeroth moment generates the standard few-group equation while the higher-moment equations generate the detailed spectral resolution within the few-group structure. It is shown that by carefully choosing the orthogonal function set (e.g., Legendre polynomials), the higher-moment equations are only coupled to the zeroth-order equation and not to each other. The decoupling makes the new method highly competitive with the standard few-group method since the computation time associated with determining the higher moments becomes negligible as a result of the decoupling. The method is verified in several one-dimensional benchmark problems typical of boiling water reactor configurations with mild to high heterogeneity.