A surrogate model based on sparse grid interpolation for boiling water reactor subchannel void distribution. (September 2019)

• Record Type: Journal Article
• Authors: Bennett, Alexander; Martin, Nicolas; Avramova, Maria
• Is Part Of: Annals of nuclear energy. Volume 131(2019)
• Page Start: 51
• Page End: 62
• Publication Date: 2019-09
• Subjects: Sparse grids -- Void distribution -- Local void model -- F-COBRA-TF -- ATRIUM 10 -- APOLLO2-A; Nuclear energy -- Periodicals; Nuclear engineering -- Periodicals; 621.4805
• DOI: 10.1016/j.anucene.2019.03.022
• Languages: English
• ISSNs: 0306-4549

Abstract

Highlights: Created a surrogate model for the prediction of the subchannel void distribution. The computational time was reduced from minutes to about a second. The surrogate model reproduced the high fidelity model with low errors. The surrogate model is coupled with a lattice physics code to provide feedback. Abstract: Boiling water reactors are simulated using nodal diffusion core simulators which rely upon homogenized and condensed cross sections from a lattice physics code. In the lattice calculation, the void distribution is typically assumed to be uniform in the radial direction. To remove this assumption, a thermal hydraulic code can be coupled with a lattice physics code to include a radial void distribution in the cross sections. To minimize the additional computational costs, a surrogate model can be generated for the thermal hydraulic code. In this research, a surrogate model is generated for the thermal hydraulic code F-COBRA-TF using sparse grid interpolation. The surrogate model is tested on how well it can reproduce the F-COBRA-TF void distribution for various conditions on the ATRIUM 10 assembly. The surrogate model is found to be effective at reproducing the F-COBRA-TF void distribution and reducing the computational costs from the order of minutes to about a second. A coupling is created between the surrogate model and the lattice physics code APOLLO2-A. Including the void distribution in the lattice physics calculation is found to have a large effect on the gadolinium worth.