Modeling and measurement of erosive burning of stick propellants

Abstract

Abstract : Interior ballistic performance of unslotted single-perforated stick propellants in a large-caliber gun could be influenced significantly by the erosive burning effect. To analyze erosive burning phenomena, a comprehensive model, with special emphasis on the interaction of turbulence and combustion, has been formulated. Experimentally, a test rig using a center-perforated cylindrical propellant grain with large web thickness (approx. 1.0 cm) was designed, constructed, and tested. The location of the instantaneous propellant burning surface was determined by the use of real time X-ray radiography. Based upon X-ray images, the instantaneous burning rate of NOSOL-363 stick propellant was found to be much higher (up to 3.2 times) than the strand burning rate under strong cross-flow conditions. Keywords: Erosive burning, Stick propellant, Theoretical modeling, Experimental measurements, k-epsilon turbulent closure, Two-variable joint probability density function, Real-time x-ray radiography.