Numerical Simulation of Gas Self-Oscillations in Gas Turbine Combustors

An economical method for numerical simulation of self-excitation of gas oscillations in low-emission combustors of gas turbine plants is developed and tested. The method is based on using an SAS SST \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$k{-}\omega$$\end{document} turbulence model and a turbulent combustion model with a modified equation for a variable degree of combustion completion. Simulating the self-excitation of gas oscillations requires that a factor associated with gas pressure oscillations is introduced into the source term of this equation. Isolation of one of the gas oscillation modes prone to self-excitation is carried out using a resonant filter operating in each cell of the computational domain. The computational results obtained using the proposed method make it possible to study the effect of design measures and operating parameters of self-oscillations and to approach the choice of measures to suppress them.