Accession Number : ADA199761


Title :   Combustion Mechanisms of Wide Distribution Propellants


Descriptive Note : Final rept. May 1984-May 1988


Corporate Author : PURDUE RESEARCH FOUNDATION LAFAYETTE IN


Personal Author(s) : Fredrick, Jr, Robert A


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a199761.pdf


Report Date : Jun 1988


Pagination or Media Count : 281


Abstract : The objective of this research is to describe the effects of oxidizer particle size distribution on the burning rate of solid propellants used in rocket motors. Current models over predict the burning rate of wide distribution (wide distribution denotes two oxidizer modes that have extreme differences in mean diameter) formulations by 40 to 200 percent indicating combustion mechanisms unique to this type of propellant. Four sets of AP/HTPB propellants were formulated to control the physical and chemical heterogenities characteristic of the propellant surface using 400 and 20 microns oxidizer particles. The propellants were tested at pressure levels from 0 to 2000 psig. An optical, distance measurement technique was developed and used to measure the local, non-steady surface deflagration of the propellant burning surface. The method uses a laser beam, synchronous detection, and closed-loop tracking to locate the surface in the hostile combustion environment. An acoustic emission technique determined average burning rates. Combustion phenomena were also accessed using high-speed photography and scanning electron microscopy. Keywords: Particle size distribution, Burning rate, Solid propellants, Rocket motors, Combustion mechanisms, AP/HTPB propellants, Laser diagnostics, Acoustic emissions, Scanning electron.


Descriptors :   *COMBUSTION , *SOLID ROCKET OXIDIZERS , *AMMONIUM PERCHLORATE , *PARTICLE SIZE , DISTRIBUTION , ELECTRONIC SCANNERS , TRACKING , LASER BEAMS , ELECTRON MICROSCOPY , SURFACES , PROPELLANTS , LASER APPLICATIONS , PRESSURE , DIAGNOSIS(GENERAL) , OXIDIZERS , ENEMY , MEAN , BURNING RATE , RANGE(DISTANCE) , INDICATORS , ACOUSTIC EMISSIONS , ROCKET ENGINES , CLOSED LOOP SYSTEMS , SOLID PROPELLANTS , HIGH SPEED PHOTOGRAPHY , DEFLAGRATION , MODELS , ENVIRONMENTS , MEASUREMENT , STEADY STATE , DIAMETERS


Subject Categories : Ammunition and Explosives


Distribution Statement : APPROVED FOR PUBLIC RELEASE