A Caltech Library Service

Numerical simulations of combustion instabilities in gas turbine combustors, with applications


Swenson, Grant Douglas (2000) Numerical simulations of combustion instabilities in gas turbine combustors, with applications. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/3QG6-JN34.


Recent advances in technology have opened up a potential market for small gas turbine power systems in the 50-100 MW range. In an effort to improve their systems, the gas-turbine industry is interested in understanding and controlling combustion instabilities as well as reducing pollutant production. To understand the dynamics inherent in a combustion system, information about the flow field behavior is required. Because of a scarcity of available experimental or numerical results for full-scale gas-turbine combustors, we decided to use numerical simulations to provide the required information about the flow field dynamics. The ability of the numerical simulations to reproduce unstable behavior in combustion environments will be presented. The investigation of the flow field dynamics has been conducted for three test cases; a planar heat source in a tube, premixed flow in a dump combustor, and premixed and diffusion flames in a full-scale gas turbine combustor. The numerically determined unsteady acoustic modes will be shown to compare well with theory and experiments. An investigation of the local heat release response to an unsteady flow field is conducted for incorporation into an approximate analysis method. The results of including a Helmholtz resonator in a dump combustor as a passive control mechanism will be presented. The production of NOx and CO will be compared between stable and unstable flow configurations. The pollutant results indicate that for the planar flame in a tube and the dump combustor, the NOx levels at the exit plane are reduced when the system is unstable.

Item Type:Thesis (Dissertation (Ph.D.))
Degree Grantor:California Institute of Technology
Division:Engineering and Applied Science
Major Option:Aeronautics
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Culick, Fred E. C. (advisor)
  • Zukoski, Edward E. (co-advisor)
Thesis Committee:
  • Unknown, Unknown
Defense Date:29 October 1999
Record Number:CaltechETD:etd-01162008-140810
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:205
Deposited By: Imported from ETD-db
Deposited On:16 Jan 2008
Last Modified:20 Dec 2019 20:03

Thesis Files

PDF (Swenson_gd_2000.pdf) - Final Version
See Usage Policy.


Repository Staff Only: item control page