Momentum and heat flux in a swirl-stabilized combustor
Published Web Locationhttps://doi.org/10.1016/S0082-0784(85)80512-9
The use of a fine-wire compensated thermocouple probe and two-color laser anemometry to measure both heat and momentum fluxes in the axial and azimuthal directions is assessed for a complex flow, swirl-stabilized laboratory combustor. Thermocouple probe perturbation and time constant variation are evaluated and the former is found to be significant in the central region of the recirculation zone. To minimize the effect of perturbation, the configuration of the probe is varied. In the recirculating region, the mean temperature is uniform with peak, instantaneous temperatures approximating the maximum adiabatic flame temperature. The maximum rms temperature approaches 250°C and occurs off-axis, just downstream of the recirculation zone. The heat flux on the centerline is negative and becomes more negative with downstream distance. Correspondingly, the temperature time series and the probability density function of the fluctuating temperature indicate that neither is cool dilution air present near the centerline nor are hot fluid particles present near the wall. This is attributed to the preferential transport of hot, low velocity fluid particles towards the centerline and cool dense gas, towards the wall by the swirl. © 1985 Combustion Institute.