VELOCITY AND TEMPERATURE MEASUREMENTS IN A PREMIXED FLAME WITHIN AN AXISYMMETRIC COMBUSTOR.

Measurements of velocity, temperature, and noise characteristics are reported for a premixed natural gas, air flame stabilized on a disc baffle located on the axis of a round pipe, and for a corresponding isothermal flow. The stability limits of the flame are identified and measurements of mean axial velocity, the variance of the corresponding fluctuations and noise intensity provided for equivalence ratios in the range 0. 7 to 1. 6. Center-line distributions of mean axial velocity, the variance of the corresponding fluctuations and mean temperature are reported and an analysis is presented of the uncertainties of the laser-anemometer instrumentation and bare-wire thermocouple measurements. It is shown that the range of equivalence ratios which allow stable length of the recirculation region are increased by combustion; and that the center-line distribution of mean temperature is comparatively uniform for more than 3 baffle diameters downstream.