Computational Flame Diagnostics for Direct Numerical Simulations with Detailed Chemistry of Transportation Fuels

Technical Report · Thu Feb 16 04:00:00 EST 2017

DOI:https://doi.org/10.2172/1343926· OSTI ID:1343926

Lu, Tianfeng ^[1]

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1. Univ. of Connecticut, Storrs, CT (United States); University of Connecticut

The goal of the proposed research is to create computational flame diagnostics (CFLD) that are rigorous numerical algorithms for systematic detection of critical flame features, such as ignition, extinction, and premixed and non-premixed flamelets, and to understand the underlying physicochemical processes controlling limit flame phenomena, flame stabilization, turbulence-chemistry interactions and pollutant emissions etc. The goal has been accomplished through an integrated effort on mechanism reduction, direct numerical simulations (DNS) of flames at engine conditions and a variety of turbulent flames with transport fuels, computational diagnostics, turbulence modeling, and DNS data mining and data reduction. The computational diagnostics are primarily based on the chemical explosive mode analysis (CEMA) and a recently developed bifurcation analysis using datasets from first-principle simulations of 0-D reactors, 1-D laminar flames, and 2-D and 3-D DNS (collaboration with J.H. Chen and S. Som at Argonne, and C.S. Yoo at UNIST). Non-stiff reduced mechanisms for transportation fuels amenable for 3-D DNS are developed through graph-based methods and timescale analysis. The flame structures, stabilization mechanisms, local ignition and extinction etc., and the rate controlling chemical processes are unambiguously identified through CFLD. CEMA is further employed to segment complex turbulent flames based on the critical flame features, such as premixed reaction fronts, and to enable zone-adaptive turbulent combustion modeling.

• Research Organization: Univ. of Connecticut, Storrs, CT (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• DOE Contract Number: SC0008622
• OSTI ID: 1343926
• Report Number(s): DOE-UCONN--16345-1
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
99 GENERAL AND MISCELLANEOUS
Computational flame diagnostics
bifurcation analysis
chemical explosive mode analysis
direct numerical simulations
dynamic adaptive chemistry
extinction
ignition
laminar flames
limit flame phenomena
mechanism reduction
turbulent combustion model
turbulent flames