A preliminary study to Assess Model Uncertainties in Fluid Flows
Abstract
The goal of this study is to assess the impact of various flow models for a simplified primary coolant loop of a light water nuclear reactor. The various fluid flow models are based on the Euler equations with an additional friction term, gravity term, momentum source, and energy source. The geometric model is purposefully chosen simple and consists of a one-dimensional (1D) loop system in order to focus the study on the validity of various fluid flow approximations. The 1D loop system is represented by a rectangle; the fluid is heated up along one of the vertical legs and cooled down along the opposite leg. A pressurizer and a pump are included in the horizontal legs. The amount of energy transferred and removed from the system is equal in absolute value along the two vertical legs. The various fluid flow approximations are compressible vs. incompressible, and complete momentum equation vs. Darcy’s approximation. The ultimate goal is to compute the fluid flow models’ uncertainties and, if possible, to generate validity ranges for these models when applied to reactor analysis. We also limit this study to single phase flows with low-Mach numbers. As a result, sound waves carry a very small amountmore »
- Authors:
- Publication Date:
- Research Org.:
- Idaho National Laboratory (INL)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 969497
- Report Number(s):
- INL/EXT-09-16995
TRN: US201002%%361
- DOE Contract Number:
- DE-AC07-05ID14517
- Resource Type:
- Technical Report
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 97 MATHEMATICS AND COMPUTING; APPROXIMATIONS; COOLANT LOOPS; ENERGY SOURCES; FLOW MODELS; FLUID FLOW; FRICTION; PRESSURIZERS; REACTORS; SOUND WAVES; WATER; model; quantification; Uncertainty
Citation Formats
Marc Oliver Delchini, and Jean C. Ragusa. A preliminary study to Assess Model Uncertainties in Fluid Flows. United States: N. p., 2009.
Web. doi:10.2172/969497.
Marc Oliver Delchini, & Jean C. Ragusa. A preliminary study to Assess Model Uncertainties in Fluid Flows. United States. doi:10.2172/969497.
Marc Oliver Delchini, and Jean C. Ragusa. Tue .
"A preliminary study to Assess Model Uncertainties in Fluid Flows". United States.
doi:10.2172/969497. https://www.osti.gov/servlets/purl/969497.
@article{osti_969497,
title = {A preliminary study to Assess Model Uncertainties in Fluid Flows},
author = {Marc Oliver Delchini and Jean C. Ragusa},
abstractNote = {The goal of this study is to assess the impact of various flow models for a simplified primary coolant loop of a light water nuclear reactor. The various fluid flow models are based on the Euler equations with an additional friction term, gravity term, momentum source, and energy source. The geometric model is purposefully chosen simple and consists of a one-dimensional (1D) loop system in order to focus the study on the validity of various fluid flow approximations. The 1D loop system is represented by a rectangle; the fluid is heated up along one of the vertical legs and cooled down along the opposite leg. A pressurizer and a pump are included in the horizontal legs. The amount of energy transferred and removed from the system is equal in absolute value along the two vertical legs. The various fluid flow approximations are compressible vs. incompressible, and complete momentum equation vs. Darcy’s approximation. The ultimate goal is to compute the fluid flow models’ uncertainties and, if possible, to generate validity ranges for these models when applied to reactor analysis. We also limit this study to single phase flows with low-Mach numbers. As a result, sound waves carry a very small amount of energy in this particular case. A standard finite volume method is used for the spatial discretization of the system.},
doi = {10.2172/969497},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Sep 01 00:00:00 EDT 2009},
month = {Tue Sep 01 00:00:00 EDT 2009}
}
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