An experimental investigation of the effects of acceleration on the combustion characteristics of an aluminized composite solid propellant

Abstract

The performance characteristics of many solid propellant rocket motors have been drastically affected by the acceleration loads imposed during flight. The two modes of acceleration are spin-induced accelerations due to spin stabilization and longitudinal accelerations due to motor thrusting. The subject investigation presents experimental results obtained from a small rocket motor subjected to various acceleration loads by use of a centrifuge. The motor was designed to minimize the effects of spin-induced vortex flow and propellant strain so that acceleration effects alone could be studied. The effects of acceleration on the ballistic characteristics of the 16 percent aluminized PB.AA solid propellant were determined at acceleration levels as high as 300g. Tests were conducted with the acceleration loads directed normal into the burning surface, normal away from burning surface, and at angles of 30° and 60° into the burning surface. As the normal acceleration load into the burning surface increased, the burning rate and the amount of residue retained within the motor increased. At orientations other than normal and into the burning surface, neither the burning rate nor the amount of residue retained increased with accelerations as high as 200g.