DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Direct Numerical Simulation of the Flow through a Randomly Packed Pebble Bed

Journal Article · · Journal of Fluids Engineering
DOI: https://doi.org/10.1115/1.4045439 · OSTI ID:1571446
 [1];  [1];  [2];  [2];  [1];  [1]
  1. Texas A & M Univ., College Station, TX (United States). Dept. of Nuclear Engineering
  2. Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Science and Engineering Division

The proposition for molten salt and high-temperature gas-cooled reactors has increased the focus on the dynamics and physics in randomly packed pebble beds. Research is being conducted on the validity of these designs as a possible contestant for fourth-generation nuclear power systems. A detailed understanding of the coolant flow behavior is required in order to ensure proper cooling of the reactor core during normal and accident conditions. In order to increase the understanding of the flow through these complex geometries and enhance the accuracy of lower-fidelity modeling, high-fidelity approaches such as direct numerical simulation (DNS) can be utilized. Nek5000, a spectral-element computational fluid dynamics code, was used to develop DNS fluid flow data. The flow domain consisted of 147 pebbles enclosed by a bounding wall. In the work presented, the Reynolds numbers ranged from 430 to 1050 based on the pebble diameter and inlet velocity. Characteristics of the flow domain such as volume averaged porosity, axial porosity, and radial porosity were studied and compared with correlations available in the literature. Friction factors from the DNS results for all Reynolds numbers were compared with correlations in the literature. First- and second-order statistics show good agreement with available experimental data. Turbulence length scales were analyzed in the flow. Reynolds stress anisotropy was characterized by utilizing invariant analysis. Overall, the results of the analysis in the current study provide deeper understanding of the flow behavior and the effect of the wall in packed beds.

Research Organization:
Texas A&M Univ., College Station, TX (United States)
Sponsoring Organization:
USDOE Office of Nuclear Energy (NE)
Grant/Contract Number:
NE0008550
OSTI ID:
1571446
Journal Information:
Journal of Fluids Engineering, Vol. 142, Issue 4; ISSN 0098-2202
Publisher:
ASMECopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 29 works
Citation information provided by
Web of Science

References (13)

Pressure Drop in a Pebble Bed Reactor Under High Reynolds Number journal November 2012
The return to isotropy of homogeneous turbulence journal June 2001
Modeling Turbulent Flows in Porous Media journal January 2020
Reynolds stress anisotropy of turbulent rough wall layers journal July 2002
The influence of confining walls on the pressure drop in packed beds journal July 2001
A DNS study of flow and heat transfer through slender fixed-bed reactors randomly packed with spherical particles journal March 2017
Zur Berechnung des Druckverlustes einphasig durchströmter Kugel- und Zylinderschüttungen journal September 1972
Druckverlust in Mehrkornschüttungen aus Kugeln journal February 1964
Correlations for wall and particle shape effects on fixed bed bulk voidage journal October 1988
Spectral and modal analysis of the flow in a helical coil steam generator experiment with large eddy simulation journal December 2019
The return to isotropy of homogeneous turbulence journal August 1977
Voidage variation in packed beds at small column to particle diameter ratio journal August 2003
Experimental investigation of cross flow mixing in a randomly packed bed and streamwise vortex characteristics using particle image velocimetry and proper orthogonal decomposition analysis journal February 2019

Figures / Tables (20)