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The two reactors at Dominion Energy’s Surry plant are among the oldest in the U.S. nuclear fleet. Yet when the plant celebrated its 50th anniversary in 2023, staff could raise a toast to the future. Surry was one of the first plants to file a subsequent license renewal (SLR) application, and in May 2021, it became official: the plant was licensed to operate for a full 80 years, extending its reactors’ lifespans into 2052 and 2053.
I. Pázsit, A. Jonsson
Nuclear Science and Engineering | Volume 167 | Number 1 | January 2011 | Pages 61-76
Technical Paper | doi.org/10.13182/NSE10-15
Articles are hosted by Taylor and Francis Online.
The dynamic space- and frequency-dependent response of a molten salt reactor (MSR) to stationary perturbations is investigated in a simple analytical model. The Green's function of the system is investigated in the general case of arbitrary fuel recirculation velocity and in the limiting case of infinite fuel velocity, which permits closed-form solutions in both the static and dynamic cases. It is found that the amplitude of the induced noise is generally higher and the domain of the point kinetic behavior valid up to higher frequencies than in a corresponding traditional system. This is due to the differing behavior of the delayed neutron precursors as compared to the traditional case. The MSR equations are not self-adjoint and the adjoint equation and adjoint function have to be constructed, which is also done here. Finally, the space-dependent neutron noise, induced by propagating perturbations of the absorption cross section, is calculated. A number of interesting properties that are relevant to full-size MSRs are found and interpreted. The results are consistent with those in traditional systems, but the domains of various behavior regimes (point kinetic, space dependent, etc.) are shifted to higher frequencies or system sizes.