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Title: A turbulence model for buoyant flows based on vorticity generation.

Abstract

A turbulence model for buoyant flows has been developed in the context of a k-{var_epsilon} turbulence modeling approach. A production term is added to the turbulent kinetic energy equation based on dimensional reasoning using an appropriate time scale for buoyancy-induced turbulence taken from the vorticity conservation equation. The resulting turbulence model is calibrated against far field helium-air spread rate data, and validated with near source, strongly buoyant helium plume data sets. This model is more numerically stable and gives better predictions over a much broader range of mesh densities than the standard k-{var_epsilon} model for these strongly buoyant flows.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Sandia National Laboratories
Sponsoring Org.:
USDOE
OSTI Identifier:
875637
Report Number(s):
SAND2005-6273
TRN: US200603%%265
DOE Contract Number:
AC04-94AL85000
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; FLOW MODELS; TURBULENT FLOW; KINETIC EQUATIONS; AIR; HELIUM; KINETIC ENERGY; VORTICES; Turbulence-Mathematical models.; Kinetic theory of liquids-Mathematical models.

Citation Formats

Domino, Stefan Paul, Nicolette, Vernon F., O'Hern, Timothy John, Tieszen, Sheldon R., and Black, Amalia Rebecca. A turbulence model for buoyant flows based on vorticity generation.. United States: N. p., 2005. Web. doi:10.2172/875637.
Domino, Stefan Paul, Nicolette, Vernon F., O'Hern, Timothy John, Tieszen, Sheldon R., & Black, Amalia Rebecca. A turbulence model for buoyant flows based on vorticity generation.. United States. doi:10.2172/875637.
Domino, Stefan Paul, Nicolette, Vernon F., O'Hern, Timothy John, Tieszen, Sheldon R., and Black, Amalia Rebecca. Sat . "A turbulence model for buoyant flows based on vorticity generation.". United States. doi:10.2172/875637. https://www.osti.gov/servlets/purl/875637.
@article{osti_875637,
title = {A turbulence model for buoyant flows based on vorticity generation.},
author = {Domino, Stefan Paul and Nicolette, Vernon F. and O'Hern, Timothy John and Tieszen, Sheldon R. and Black, Amalia Rebecca},
abstractNote = {A turbulence model for buoyant flows has been developed in the context of a k-{var_epsilon} turbulence modeling approach. A production term is added to the turbulent kinetic energy equation based on dimensional reasoning using an appropriate time scale for buoyancy-induced turbulence taken from the vorticity conservation equation. The resulting turbulence model is calibrated against far field helium-air spread rate data, and validated with near source, strongly buoyant helium plume data sets. This model is more numerically stable and gives better predictions over a much broader range of mesh densities than the standard k-{var_epsilon} model for these strongly buoyant flows.},
doi = {10.2172/875637},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Oct 01 00:00:00 EDT 2005},
month = {Sat Oct 01 00:00:00 EDT 2005}
}

Technical Report:

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