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Title: Rapid compression machine study of a premixed, variable inlet density and flow rate, confined turbulent jet

Authors:
; ; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1324351
Grant/Contract Number:
CBET-1258581
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Combustion and Flame
Additional Journal Information:
Journal Volume: 169; Journal Issue: C; Related Information: CHORUS Timestamp: 2017-10-06 15:33:14; Journal ID: ISSN 0010-2180
Publisher:
Elsevier
Country of Publication:
United States
Language:
English

Citation Formats

Gholamisheeri, Masumeh, Thelen, Bryce C., Gentz, Gerald R., Wichman, Indrek S., and Toulson, Elisa. Rapid compression machine study of a premixed, variable inlet density and flow rate, confined turbulent jet. United States: N. p., 2016. Web. doi:10.1016/j.combustflame.2016.05.001.
Gholamisheeri, Masumeh, Thelen, Bryce C., Gentz, Gerald R., Wichman, Indrek S., & Toulson, Elisa. Rapid compression machine study of a premixed, variable inlet density and flow rate, confined turbulent jet. United States. doi:10.1016/j.combustflame.2016.05.001.
Gholamisheeri, Masumeh, Thelen, Bryce C., Gentz, Gerald R., Wichman, Indrek S., and Toulson, Elisa. 2016. "Rapid compression machine study of a premixed, variable inlet density and flow rate, confined turbulent jet". United States. doi:10.1016/j.combustflame.2016.05.001.
@article{osti_1324351,
title = {Rapid compression machine study of a premixed, variable inlet density and flow rate, confined turbulent jet},
author = {Gholamisheeri, Masumeh and Thelen, Bryce C. and Gentz, Gerald R. and Wichman, Indrek S. and Toulson, Elisa},
abstractNote = {},
doi = {10.1016/j.combustflame.2016.05.001},
journal = {Combustion and Flame},
number = C,
volume = 169,
place = {United States},
year = 2016,
month = 7
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.combustflame.2016.05.001

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  • The effects of tangential strain rate and curvature on the surface density function (SDF) and on source terms within the SDF transport equation are studied for lean methane-air and hydrogen-air flames using two-dimensional direct numerical simulations with detailed chemistry. A positive correlation is observed between the SDF and the tangential strain rate, and this is explained in terms of the interaction between the local tangential strain rate and the dilatation rate due to heat release. Curvature is also seen to affect the SDF through the curvature response of both tangential strain rate and dilatation rate on a given flame isosurface.more » Strain rate and curvature are found to have an appreciable effect on several terms of the SDF transport equation. The SDF straining term in both methane and hydrogen flames is correlated positively with tangential strain rate, as expected, and is also correlated negatively with curvature. For methane flames, the SDF propagation term is found to correlate negatively with flame curvature toward the reactant side of the flame and positively toward the product side. By contrast, for hydrogen flames the SDF propagation term is negatively correlated with curvature throughout the flame brush. The variation of the SDF curvature term with local flame curvature for both methane and hydrogen flames is found to be nonlinear due to the additional stretch induced by the tangential diffusion component of the displacement speed. Physical explanations are provided for all of these effects, and the modeling implications are considered in detail. (author)« less
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  • Large-scale strain rate field, a resolved quantity which is easily computable in large-eddy simulations (LES), could have profound effects on the premixed flame properties by altering the turbulent flame speed and inducing local extinction. The role of the resolved strain rate has been investigated in a posterior LES study of GE lean premixed dry low NOx emissions LM6000 gas turbine combustor model. A novel approach which is based on the coupling of the lineareddy model with a one-dimensional counter-flow solver has been applied to obtain the parameterizations of the resolved premixed flame properties in terms of the reactive progress variable,more » the local strain rate measure, and local Reynolds and Karlovitz numbers. The strain rate effects have been analyzed by comparing LES statistics for several models of the turbulent flame speed, i.e, with and without accounting for the local strain rate effects, with available experimental data. The sensitivity of the simulation results to the inflow velocity conditions as well as the grid resolution have been also studied. Overall, the results suggest the necessity to represent the strain rate effects accurately in order to improve LES modeling of the turbulent flame speed.« less