Burning-rate behavior in aluminized wide-distribution AP composite propellants

M. Q. Brewster, J. C. Mullen

Research output: Contribution to journalArticlepeer-review

Abstract

Burning-rate behavior of aluminized, wide-distribution ammonium-perchlorate (AP), hydroxyl-terminated-polybutadiene (HTPB) binder composite propellants, both 2D laminates and 3D particulate propellants, is investigated experimentally. Very fine (2-μm) AP (FAP) is used at a high FAP/binder ratio (75/25) with either coarse (>200 μm) AP (CAP) particles (3D particulate propellants) or pressed AP slabs (simulating CAP particles in over-ventilated, 2D laminates). The results indicate that, while aluminum does not significantly alter the AP/binder flame structure, it can either increase the burning rate via radiative feedback or decrease it via inert heat-sink effects, depending on pressure (competing conductive heat feedback). Otherwise, the AP/binder flame structure is similar to that found previously for non-aluminized laminates, with minor differences. The FAP/HTPB-matrix burns with a one-dimensional premixed flame not hot enough to ignite aluminum, but hot enough to self-deflagrate if a modest amount of an external radiant flux (in the case considered, supplied by aluminum ignited downstream by the CAP/matrix flame) is present. The CAP/matrix interaction flame burns in either a split-diffusion or merged, partially premixed mode, depending on pressure and fuel-layer thickness. A correlation between the burningrate pressure exponent and the CAP/matrix flame-regime pressure dependence is found in terms of the Peclet number in accordance with a simple, conserved-scalar (mixture fraction) theory.

Original languageEnglish (US)
Pages (from-to)200-208
Number of pages9
JournalCombustion, Explosion and Shock Waves
Volume47
Issue number2
DOIs
StatePublished - Mar 2011

Keywords

  • aluminized
  • ammonium perchlorate
  • burning rate
  • composite propellant
  • laminate

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Fuel Technology
  • Energy Engineering and Power Technology
  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Burning-rate behavior in aluminized wide-distribution AP composite propellants'. Together they form a unique fingerprint.

Cite this