CFD analysis of a liquid-mercury target for the Spallation Neutron Source

Journal Article · Tue Sep 01 04:00:00 EDT 1998 · Transactions of the American Nuclear Society

OSTI ID:644292

Wendel, M W; Tov, M S ^[1]

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1. Oak Ridge National Lab., TN (United States)

The Spallation Neutron Source (SNS) is a high-power accelerator-based pulsed spallation source being designed by a multilaboratory team led by Oak Ridge National Laboratory to achieve high fluxes of neutrons for scientific experiments. Computational fluid dynamics (CFD) is being used to analyze the design of the SNS target. The target is subjected to the neutronic (internal) heat generation that results from the proton collisions with the mercury nuclei. The liquid mercury serves as the coolant as well as the target, and the target design must allow for heat removal from the stainless steel target enclosure. Recirculation and stagnation zones within the target are of particular concern due to the possibility that they will develop into local hot spots. These zones exist since the target design includes a complete U-turn flow redirection. Although the primary concern is that the target is adequately cooled, the target pressure drop must also be considered because it directly affects structural loading and required pumping power. The wall heat transfer is particularly important in the cooling of the window and the interior flow baffle. Another concern that has not yet been analyzed is the pulsation dynamics that occur on a microsecond timescale and affect the flow through thermal shocks. Two-dimensional CFD analysis has been completed, and the results compared favorably with spreadsheet calculations based on empirical heat transfer and pressure drop correlations, as well as with published experimental data for total pressure drop. This work has been extended to include a full three-dimensional model of the target geometry, including the liquid mercury, stainless steel pressure boundary, and supplemental liquid-mercury cooling jacket channels on the outside of the target.

• OSTI ID: 644292
• Report Number(s): CONF-980606--
• Journal Information: Transactions of the American Nuclear Society, Journal Name: Transactions of the American Nuclear Society Vol. 78; ISSN TANSAO; ISSN 0003-018X
• Country of Publication: United States
• Language: English

Related Subjects

07 ISOTOPE AND RADIATION SOURCES
43 PARTICLE ACCELERATORS
ACCELERATOR FACILITIES
COMPUTER-AIDED DESIGN
FLUID MECHANICS
HEAT TRANSFER
LIQUID METALS
NEUTRON SOURCES
PRESSURE DROP
TARGETS