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NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
O. E. Dwyer
Nuclear Science and Engineering | Volume 25 | Number 4 | August 1966 | Pages 343-358
Technical Paper | doi.org/10.13182/NSE66-A18553
Articles are hosted by Taylor and Francis Online.
Circumferential variations of temperature and local heat transfer coefficients were obtained for sodium flowing in-line through a staggered rod bundle. The conditions of the study were: turbulent flow, uniform heat flux from the surfaces of all rods, and fully developed velocity and temperature profiles. The rods were spaced in an equilateral triangular array, and the pitch:diameter (P:D) ratio was varied down to 1.10. It was shown that the annulus model is satisfactory for estimating average heat transfer coefficients for P:D ratios down to about 1.3, but below this, it gives increasingly high results, e.g., at P:D = 1.10, an annulus-model coefficient can be high by about a factor of 2. It was found that circumferential temperature variations are not large, e.g., at P:D = 1.10, this variation is about twice the average temperature drop from the rod surface to flowing metal. Compared to the P:D ratio, the Peclet number has little influence on the reduction in the average heat transfer coefficient, or the circumferential variation of the surface temperature. At a P:D ratio of 1.40, the local coefficient is estimated to vary by a factor of only 1.2; at 1.20, by a factor of 1.7; and at 1.10, by a factor of ≈ 100.