Scale adaptive turbulence modeling for in-vessel sodium thermal hydraulics

Computational fluid dynamics is a powerful tool for the simulation of nuclear reactor coolant flows, such as in sodium fast reactors. In these reactors, the phenomenon of thermal striping -- characterized by oscillatory turbulent mixing of non-isothermal coolant flows -- has the potential to damage the structural integrity of reactor instrumentation and structural materials. At present, large eddy simulation is the only turbulence modeling approach which can sufficiently resolve and predict the mixing behavior of thermal striping, including temperature fluctuation and fluctuation frequencies. The extreme computational cost requirements of large eddy simulation application preclude the use of CFD for large engineering applications. In this work, the performance of the newly developed STRUCT hybrid turbulence model (Lenci, 2016) is evaluated on three representative test cases in comparison to traditional unsteady Reynolds-Averaged Navier-Stokes (URANS) and large eddy simulation (LES) models. Results indicate excellent potential for application of the STRUCT approach to sodium thermal striping flows. Best practice guidelines are developed and discussed.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Nuclear Science and Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2016

Author dc:creator

• Acton, Michael (Michael John)

Advisor dc:contributor.advisor

• Emilio Baglietto.

• Nuclear Science and Engineering.

Statement dc:rights

• MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/107022

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/107022