Combustor and Nozzle Effects on Particulate Behavior in Solid Rocket Motors.

摘要

An investigation was conducted using a subscale solid rocket motor to measure the effect of nozzle residence time on the behavior of Al203 particles to assess the applicability of subscale motor data to full-scale motors and to measure the effects of nozzle entrance particle size distribution on the slag accumulated with submerged nozzles. Although particles as large as 140 micrometers were present at the nozzle entrance, most of the particulate mass was contained in much smaller particles. This observation is in good agreement with the small mass that accumulated above the submerged nozzle. It was found that both particle breakup and collision coalescence occurred across the exhaust nozzle, with a significant increase in the mass fraction of small (<2 micrometers) particles. Increasing the nozzle residence time enhanced particle breakup but did not affect the maximum plume particle size. Thus, full-scale motors are expected to have a higher percentage of mass in particles less than 2 micrometers than subscale motors but with similar diameters of the largest particles.