Flow and Combustion Characteristics of a Two Dimensional Spouted Bed

摘要

A two dimensional spouted bed laboratory combustor has been designed and constructed with the objective of studying the interaction among the gas flow, particle flow, and combustion. The facility, designed for a maximum thermal power of 20 kW, has a quartz front wall providing full optical access to particle flows and combustion processes. The combustor was characterized in terms of pressure, temperature, gas velocity, and particle velocity profiles and operating limits. Initial studies employed premixed propane and air and a fixed bed height, bed material, injector slot width, and combustor geometry. As in previous investigations of axisymmetric spouted beds, the ratio of particle mass circulation rate to jet mass flow rate was observed to be about ten. Combustion increased this ratio by about 10%. A pulsating mode of operation was noted with a characteristic frequency of about 10 Hz, controlled by the interaction of the particle and gas flows. In the present configuration internal heat recirculation is approximately balanced by heat losses so that lean and rich flammability limits are extended only slightly beyond those of premixed laminar flames. (ERA citation 07:044450)