Linear Stability Analysis in a Gas Turbine Combustor Using Thermoacoustic Models

열음향 해석 모델을 통한 가스터빈 연소기에서의 선형 안정성 분석

  • 김대식 (강릉원주대학교 기계자동차공학부)
  • Received : 2012.02.23
  • Accepted : 2012.04.27
  • Published : 2012.06.30

Abstract

In this study, thermoacoustic analysis model was developed in order to predict both eigenfrequencies and initial growth rate of combustion instabilities for lean premixed gas turbine combustors. As a first step, a model combustor and nozzle were selected and analytical linear equations for thermoacoustic waves were derived for a given combustion system. Then, methods showing how the equations can be used for analysis of the combustion instability were suggested. It was found that the prediction results showed a good agreement with the measurements. However, there were some limitation in growth rate predictions, which were related with over-simplification of flame structure, acoustic boundary conditions, and temperature distribution in the combustor.

Keywords

References

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