A Study on a Twin Valueless Pulse Burner : 1st Report, Effects of Mixture Ratio and Mass Flux on the Pulse Combustion Stability

Abstract

Ensemble-averaged heat release rates and pressures in a combustion chamber have been measured to better understand the operating characteristics of a twin valveless pulse burner. An OH chemiluminescence intensity measurement system and pressure transducers were used as diagnostic tools. Based on the Rayleigh's criterion, the effects of changing the equivalence ratio and the mass flux on the combustion stabilities are discussed. Results show that the phase difference between heat release rate and pressure significantly affects the pulse combustion stability. In addition, the phase difference does not depend on the mass flux but on the equivalence ratio, this indicating that the fuel/ air mixing is a determining factor in the phase relationship. Also, it was found that the operating frequency increased with increasing mass flux, while it decreased with increasing equivalence ratio.