CaltechTHESIS
  A Caltech Library Service

Modeling and simulation of axisymmetric stagnation flames

Citation

Sone, Kazuo (2007) Modeling and simulation of axisymmetric stagnation flames. Dissertation (Ph.D.), California Institute of Technology. http://resolver.caltech.edu/CaltechETD:etd-04252007-170838

Abstract

Laminar flame modeling is an important element in turbulent combustion research. The accuracy of a turbulent combustion model is highly dependent upon our understanding of laminar flames and their behavior in many situations. How much we understand combustion can only be measured by how well the model describes and predicts combustion phenomena. One of the most commonly used methane combustion models is GRI-Mech 3.0. However, how well the model describes the reacting flow phenomena is still uncertain even after many attempts to validate the model or quantify uncertainties. In the present study, the behavior of laminar flames under different aerodynamic and thermodynamic conditions is studied numerically in a stagnation-flow configuration. In order to make such a numerical study possible, the spectral element method is reformulated to accommodate the large density variations in methane reacting flows. In addition, a new axisymmetric basis function set for the spectral element method that satisfies the correct behavior near the axis is developed, and efficient integration techniques are developed to accurately model axisymmetric reacting flow within a reasonable amount of computational time. The numerical method is implemented using an object-oriented programming technique, and the resulting computer program is verified with several different verification methods. The present study then shows variances with the commonly used GRI-Mech 3.0 chemical kinetics model through a direct simulation of laboratory flames that allows direct comparison to experimental data. It is shown that the methane combustion model based on GRI-Mech 3.0 works well for methane-air mixtures near stoichiometry. However, GRI-Mech 3.0 leads to an overprediction of laminar flame speed for lean mixtures and an underprediction for rich mixtures. This result is slightly different from conclusion drawn in previous work, in which experimental data are compared with a one-dimensional numerical solutions. Detailed analysis reveals that flame speed is sensitive to even slight flame front curvature as well as its finite extension in the radial direction. Neither of these can be incorporated in one-dimensional flow modeli

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:axisymmetric; axisymmetric parity condition; combustion; GRI Mech; methane; modeling; object-oriented programming; reacting; reacting flow; scientific computing; simulation; spectral element method; validation; verification
Degree Grantor:California Institute of Technology
Division:Engineering and Applied Science
Major Option:Aeronautics
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Dimotakis, Paul E. (advisor)
  • Meiron, Daniel I. (advisor)
Thesis Committee:
  • Dimotakis, Paul E. (chair)
  • Meiron, Daniel I. (co-chair)
  • Pullin, Dale Ian
  • Goodwin, David G.
  • Shepherd, Joseph E.
Defense Date:18 May 2007
Record Number:CaltechETD:etd-04252007-170838
Persistent URL:http://resolver.caltech.edu/CaltechETD:etd-04252007-170838
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:1500
Collection:CaltechTHESIS
Deposited By: Imported from ETD-db
Deposited On:30 May 2007
Last Modified:26 Dec 2012 02:38

Thesis Files

[img]
Preview
PDF (abstract_concise.pdf) - Final Version
See Usage Policy.

9Kb
[img] Archive (ZIP) (AppendixD_Supplemental.zip) - Final Version
See Usage Policy.

53Kb
[img]
Preview
PDF (thesis.pdf) - Final Version
See Usage Policy.

8Mb
[img]
Preview
PDF (thesis_part1.pdf) - Final Version
See Usage Policy.

1149Kb
[img]
Preview
PDF (thesis_part2.pdf) - Final Version
See Usage Policy.

4Mb
[img]
Preview
PDF (thesis_part3.pdf) - Final Version
See Usage Policy.

2857Kb

Repository Staff Only: item control page