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NRC begins special inspection at Hope Creek
The Nuclear Regulatory Commission is conducting a special inspection at Hope Creek nuclear plant in New Jersey to investigate the cause of repeated inoperability of one of the plant’s emergency diesel generators, the agency announced in a February 25 news release.
K. S. Smith
Nuclear Science and Engineering | Volume 81 | Number 3 | July 1982 | Pages 451-458
Technical Paper | doi.org/10.13182/NSE82-A20286
Articles are hosted by Taylor and Francis Online.
An investigation of first-order perturbation (FOP) methods for computing sample worths has been performed. It is demonstrated that conventional cell homogenization methods introduce errors into FOP reactivity calculations because the intracell structure of adjoint fluxes is neglected. These errors are such that the conventional FOP reactivity expression is not accurate to first order, even in the limit of infinitesimal perturbations. A method for avoiding such approximations is introduced and applied to the calculation of small sample worths in plate-type fast reactor critical assemblies. It is demonstrated that errors introduced by real flux weighting of cross sections are such that homogenized FOP reactivity calculations overestimate fissile material worths in several critical assemblies by 5 to 10%. It is shown that these errors arise because of the heterogeneous nature of plate-type critical assemblies, and when appropriate reactivity calculations (which account for spatial heterogeneity of adjoint fluxes) are performed, a significant fraction of the long-standing central worth discrepancy is eliminated.