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The progress so far: An update on the Reactor Pilot Program
It has been about three months since the Department of Energy named 10 companies for its new Reactor Pilot Program, which maps out how the DOE would meet the goal announced by executive order in May of having three reactors achieve criticality by July 4, 2026.
Christophe Suteau, Maurice Chiron, Gilles Arnaud
Nuclear Science and Engineering | Volume 147 | Number 1 | May 2004 | Pages 43-55
Technical Paper | doi.org/10.13182/NSE04-A2417
Articles are hosted by Taylor and Francis Online.
This study proposes an improvement of the general formalism for calculating gamma-ray buildup factors in multilayer shields developed by Assad et al. The main modification concerns the treatment of the double-layer shield formed by the two first layers of a multilayer shield. Instead of replacing the double-layer shield with an equivalent thickness of the layer of the second material, the improved general formalism replaces it with a single-layer shield made of an appropriate material. The determination of the appropriate material is implemented into MERCURE-6.1 thanks to neural networks trained on a large set of various configurations.One-dimensional comparisons with the TWODANT transport Sn code shows the accuracy of the new formalism for shields composed of three and five layers. Indeed, for three-layer shields with an infinitesimal second layer and for multilayer shields composed of numerous thin layers (more than 15), MERCURE-6.1 matches the reference data quite well. The MERCURE-6.1 ability to solve three-dimensional realistic cases is highlighted by comparisons to the TRIPOLI-4 and MCNP-4C Monte Carlo codes.
