Development of Multiphysics (Multiphase CFD + MCNP) simulation for generic solution vessel power calculation
Abstract
The current study aims to predict the steady state power of a generic solution vessel and to develop a corresponding heat transfer coefficient correlation for a Moly99 production facility by conducting a fully coupled multiphysics simulation. A prediction of steady state power for the current application is inherently interconnected between thermal hydraulic characteristics (i.e. Multiphase computational fluid dynamics solved by ANSYSFluent 17.2) and the corresponding neutronic behavior (i.e. particle transport solved by MCNP6.2) in the solution vessel. Thus, the development of a coupling methodology is vital to understand the system behavior at a variety of system design and postulated operating scenarios. In this study, we report on the keffective (keff) calculation for the baseline solution vessel configuration with a selected solution concentration using MCNP Kcode modeling. The associated correlation of thermal properties (e.g. density, viscosity, thermal conductivity, specific heat) at the selected solution concentration are developed based on existing experimental measurements in the open literature. The numerical coupling methodology between multiphase CFD and MCNP is successfully demonstrated, and the detailed coupling procedure is documented. In addition, improved coupling methods capturing realistic physics in the solution vessel thermalneutronic dynamics are proposed and tested further (i.e. dynamic height adjustment, mullcell approach). Asmore »
 Authors:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Publication Date:
 Research Org.:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org.:
 USDOE National Nuclear Security Administration (NNSA)
 OSTI Identifier:
 1371685
 Report Number(s):
 LAUR1725931
 DOE Contract Number:
 AC5206NA25396
 Resource Type:
 Technical Report
 Country of Publication:
 United States
 Language:
 English
 Subject:
 22 GENERAL STUDIES OF NUCLEAR REACTORS
Citation Formats
Kim, Seung Jun, and Buechler, Cynthia Eileen. Development of Multiphysics (Multiphase CFD + MCNP) simulation for generic solution vessel power calculation. United States: N. p., 2017.
Web. doi:10.2172/1371685.
Kim, Seung Jun, & Buechler, Cynthia Eileen. Development of Multiphysics (Multiphase CFD + MCNP) simulation for generic solution vessel power calculation. United States. doi:10.2172/1371685.
Kim, Seung Jun, and Buechler, Cynthia Eileen. 2017.
"Development of Multiphysics (Multiphase CFD + MCNP) simulation for generic solution vessel power calculation". United States.
doi:10.2172/1371685. https://www.osti.gov/servlets/purl/1371685.
@article{osti_1371685,
title = {Development of Multiphysics (Multiphase CFD + MCNP) simulation for generic solution vessel power calculation},
author = {Kim, Seung Jun and Buechler, Cynthia Eileen},
abstractNote = {The current study aims to predict the steady state power of a generic solution vessel and to develop a corresponding heat transfer coefficient correlation for a Moly99 production facility by conducting a fully coupled multiphysics simulation. A prediction of steady state power for the current application is inherently interconnected between thermal hydraulic characteristics (i.e. Multiphase computational fluid dynamics solved by ANSYSFluent 17.2) and the corresponding neutronic behavior (i.e. particle transport solved by MCNP6.2) in the solution vessel. Thus, the development of a coupling methodology is vital to understand the system behavior at a variety of system design and postulated operating scenarios. In this study, we report on the keffective (keff) calculation for the baseline solution vessel configuration with a selected solution concentration using MCNP Kcode modeling. The associated correlation of thermal properties (e.g. density, viscosity, thermal conductivity, specific heat) at the selected solution concentration are developed based on existing experimental measurements in the open literature. The numerical coupling methodology between multiphase CFD and MCNP is successfully demonstrated, and the detailed coupling procedure is documented. In addition, improved coupling methods capturing realistic physics in the solution vessel thermalneutronic dynamics are proposed and tested further (i.e. dynamic height adjustment, mullcell approach). As a key outcome of the current study, a multiphysics coupling methodology between MCFD and MCNP is demonstrated and tested for four different operating conditions. Those different operating conditions are determined based on the neutron source strength at a fixed geometry condition. The steady state powers for the generic solution vessel at various operating conditions are reported, and a generalized correlation of the heat transfer coefficient for the current application is discussed. The assessment of multiphysics methodology and preliminary results from various coupled calculations (power prediction and heat transfer coefficient) can be further utilized for the system code validation and generic solution vessel design improvement.},
doi = {10.2172/1371685},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 7
}

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