Convective Heat Transfer in a Gas-Fired Pulsating Combustor

Abstract

The effect of longitudinal combustion-driven oscillations on convective heat transfer rates was studied using a tubular, propane-fired combustor which resonated as a quarter-wavelength organ pipe at a frequency of 100 cps. The combustor was provided with damping tubes of variable length which enabled the amplitude of the oscillations to be varied, to the extent of damping them out completely. Heat transfer coefficients were measured with and without the presence of combustion-driven oscillations. It was found that heat transfer coefficients were highest at a position of maximum velocity amplitude, where improvements of over 100 percent were obtained. Satisfactory prediction of the effects of the oscillations was obtained by using the quasisteady-state theory.