skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Numerical simulations of a mixed momentum-driven and buoyancy-driven jet in a large enclosure for nuclear reactor severe accident analysis

Authors:
; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1412939
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Nuclear Engineering and Design
Additional Journal Information:
Journal Volume: 312; Journal Issue: C; Related Information: CHORUS Timestamp: 2017-12-11 01:37:21; Journal ID: ISSN 0029-5493
Publisher:
Elsevier
Country of Publication:
Netherlands
Language:
English

Citation Formats

Carasik, Lane B., Sebilleau, Frédéric, Walker, Simon P., and Hassan, Yassin A. Numerical simulations of a mixed momentum-driven and buoyancy-driven jet in a large enclosure for nuclear reactor severe accident analysis. Netherlands: N. p., 2017. Web. doi:10.1016/j.nucengdes.2016.10.053.
Carasik, Lane B., Sebilleau, Frédéric, Walker, Simon P., & Hassan, Yassin A. Numerical simulations of a mixed momentum-driven and buoyancy-driven jet in a large enclosure for nuclear reactor severe accident analysis. Netherlands. doi:10.1016/j.nucengdes.2016.10.053.
Carasik, Lane B., Sebilleau, Frédéric, Walker, Simon P., and Hassan, Yassin A. Wed . "Numerical simulations of a mixed momentum-driven and buoyancy-driven jet in a large enclosure for nuclear reactor severe accident analysis". Netherlands. doi:10.1016/j.nucengdes.2016.10.053.
@article{osti_1412939,
title = {Numerical simulations of a mixed momentum-driven and buoyancy-driven jet in a large enclosure for nuclear reactor severe accident analysis},
author = {Carasik, Lane B. and Sebilleau, Frédéric and Walker, Simon P. and Hassan, Yassin A.},
abstractNote = {},
doi = {10.1016/j.nucengdes.2016.10.053},
journal = {Nuclear Engineering and Design},
number = C,
volume = 312,
place = {Netherlands},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.nucengdes.2016.10.053

Save / Share:
  • A three-dimensional thermal-hydraulic code using boundary-fitted coordinates systems has been developed to predict incompressible flows with complex geometries and large variations of physical properties. This code has been applied to a buoyancy-driven exchange flow in an enclosed space consisting of an upper and lower hemisphere connected with a circular vertical pipe. The computational results have been compared with experiments. It was found that the computed heat transfer rate was smaller than that obtained from the experimental correlation in a single hemisphere at large Rayleigh number. This may be attributed to the effect on the flow behavior of a large variationmore » of gas properties. Unsteady and asymmetric flow patterns such as observed in the experiments were numerically obtained in the vertical pipe.« less
  • Buoyancy-driven flows in enclosures play a vital role in many engineering applications such as double glazing, ventilation of rooms, nuclear reactor insulation, solar energy collection, cooling of electronic components, and crystal growth in liquids. Here, numerical study on buoyancy-driven laminar flow in an inclined square enclosure heated from one side and cooled from the adjacent side is conducted using finite difference methods. The effect of inclination angle on fluid flow and heat transfer is investigated by varying the angle of inclination between 0{degree} and 360{degree}, and the results are presented in the form of streamlines and isotherms for different inclinationmore » angles and Rayleigh numbers. On the basis of the numerical data, the authors determine the critical values of the inclination angle at which the rate of the transfer within the enclosure is either maximum or minimum.« less
  • The role played by magnetic fields in the intracluster medium (ICM) of galaxy clusters is complex. The weakly collisional nature of the ICM leads to thermal conduction that is channeled along field lines. This anisotropic heat conduction profoundly changes the instabilities of the ICM atmosphere, with convective stabilities being driven by temperature gradients of either sign. Here, we employ the Athena magnetohydrodynamic code to investigate the local non-linear behavior of the heat-flux-driven buoyancy instability (HBI) relevant in the cores of cooling-core clusters where the temperature increases with radius. We study a grid of two-dimensional simulations that span a large rangemore » of initial magnetic field strengths and numerical resolutions. For very weak initial fields, we recover the previously known result that the HBI wraps the field in the horizontal direction, thereby shutting off the heat flux. However, we find that simulations that begin with intermediate initial field strengths have a qualitatively different behavior, forming HBI-stable filaments that resist field-line wrapping and enable sustained vertical conductive heat flux at a level of 10%-25% of the Spitzer value. While astrophysical conclusions regarding the role of conduction in cooling cores require detailed global models, our local study proves that systems dominated by the HBI do not necessarily quench the conductive heat flux.« less