Abstract
ABSTRACT In this paper, both optical and acoustic approaches have been carried out successfully on flame blowout in premixed combustor G30 at atmospheric pressure. This work characterizes the behavior of a swirl stabilized propane C3H8 combustor, running at high temperature swirl air. Two cases have been studied in this paper, in the first case; the flame blowout limit by shutting down the main fuel supply of the stable flame, in the other case by shutting down the main supply of unstable flame. High speed camera imaging of a stable and unstable flames at and near blowout conditions are also presented. During this phenomena of flame blowout, two different techniques have been applied an optical emission system to measure the visible global chemiluminescence emissions of two different radicals of C2* and CH* with an optic wavelength filters of 516 ± 2.5 nm and 430 ± 5 nm respectively, the other technique is the microphone system, which is used to measure the acoustic emission from the combustor simultaneously with the optical system.. A typical raw image of an instantaneous flame structure under stable-blowout and unstable-blowout conditions are also presented in this paper. For farther information about the acoustic pressure and chemiluminescence emissions of CH* and 2 C *, the power spectrum of signals just before the flame blowout has been also calculated at different condition. It has been demonstrated that optical digital acquisition and acoustic emissions processing is a powerful combination in the investigation, and have provided valuable physical insights into the complex combustion dynamics inside a gas turbine combustor.