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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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Nuclear new build procurement considerations
It may seem counterintuitive, but the best time to enhance the ability to support operations and maintenance for a new plant is before construction starts. This is one of many lessons learned by the currently operating nuclear fleet. As construction and startup of many nuclear facilities was completed, it quickly became evident that the ability to efficiently support operations and maintenance was limited. Most of the information necessary to establish and manage procurement of spare and replacement items, maintenance, and configuration of the facilities was unavailable and had to be gathered on a case-by-case, “on-demand” basis. Absence of necessary information and the associated challenges resulted in the need for staff augmentation and multiyear-long projects to develop equipment bills of material and maintenance programs and to perform technical evaluations for the huge quantities of spare and replacement items being requested.
Hoai Nam Tran, Christophe Demazière
Nuclear Science and Engineering | Volume 175 | Number 3 | November 2013 | Pages 340-351
Technical Paper | doi.org/10.13182/NSE12-49
Articles are hosted by Taylor and Francis Online.
This paper presents the development of a neutronic and kinetic solver for neutron noise calculations in hexagonal geometries. The tool is developed based on diffusion theory with multienergy groups and several groups of delayed neutron precursors allowing the solutions of forward and adjoint problems of static and dynamic states. The tool is applicable to both thermal and fast systems with hexagonal geometries. In the dynamic problems, the small stationary fluctuations of macroscopic cross sections are considered as noise sources, then the induced first-order noise is solved fully in the frequency domain. Numerical algorithms for solving the static and noise equations are implemented using finite differences for spatial discretization and a power iterative solution. A coarse-mesh finite difference technique for accelerating the convergence has been adopted. Verification calculations have been performed and compared to analytical solutions based on a two-dimensional homogeneous system with two energy groups and one group of delayed neutron precursors, in which pointlike perturbations of thermal absorption cross section at central and noncentral positions are considered as noise sources.