Dynamic Combustion of Functionally Graded Additively Manufactured Composite Solid Propellant

Autor: I. Emre Gunduz, Jeffrey F. Rhoads, Monique McClain, Steven F. Son, Aaron Afriat, Brandon J. Montano
Přispěvatelé: Naval Postgraduate School (U.S.)
Rok vydání: 2021
Předmět:
Zdroj: Journal of Propulsion and Power. 37:725-732
ISSN: 1533-3876
DOI: 10.2514/1.b38282
Popis: 17 USC 105 interim-entered record; under review. The article of record as published may be found at http://dx.doi.org/10.2514/B38282 Typically, the burning surface of a composite solid propellant is controlled through grain geometry and formulation. However, combustion studies of grains constructed from different propellant formulations at fine scales (nominally 1 mm) are not readily accessible in open literature. With additive manufacturing, such configurations can be investigated easily. Propellants with a faster burning inner layer (enhanced with either 1 wt.% iron oxide or 5 wt.% nanoaluminum) were 3D printed between two layers of slower burning 85 wt.% ammonium perchlorate/hydroxyl-terminated polybutadiene propellant. The dynamic combustion behavior of the layered propellant was investigated at pressures ranging from 3.45 to 10.34 MPa. Overall, an increase in the burning surface area, without interlayer delamination, was observed. The driving force behind the propellant surface area increase was the difference in the burning rate between the layers. In addition, the nanoaluminum propellant layer had a more stable burning rate exponent than the cast nanoaluminum propellant. Overall, only a small addition of catalyzed propellant was needed to increase the burning rate of the bulk material. The results of this study lay the foundation for functionally grading propellant grains, which could tailor the thrust profile of solid rocket motors and gun propellants. NASA Space Technology Research Fellowship 80NSSC17K0176
Databáze: OpenAIRE