Laser-recoil response of AP-HTPB propellants (1-5 atm): Selective pyrolysis response

S. R. Hickman, M. Q. Brewster

Research output: Contribution to conferencePaper

Abstract

The combustion of HTPB propellants containing fine AP was investigated using laser-driven, combustion recoil at [l to 5 atm. At 1 atm, binder-rich (70 to 75% AP), monomodal fine-AP (2 to 50 μm) propellants exhibit a prominent secondary (non-QSHOD) laser-driven response peak at 100 to 300 Hz, with frequency varying inversely with AP size. Adding coarse AP (resulting in a wide, bimodal AP distribution) causes the secondary response to disappear at 1 atm. Raising the pressure to 2 atm causes the secondary response to reappear and increase in frequency to 600-800 Hz (2 μm AP). This oscillatory combustion behavior is attributed to time-varying selective or disproportionate pyrolysis of AP and HTPB, (unsteady accumulation and depletion of AP at the propellant surface) and the associated compositional (stoichiometric) fluctuations that occur in the fuel-rich, premixed gas phase reaction zone adjacent to the fine-AP/HTPB solid region. Low Peclet number appears to be a requirement of achieving this condition. Undriven combustion recoil and thermocouple measurements at 1 atm exhibited spontaneous combustion and gas phase temperature oscillations in the monomodal fine-AP propellants and corroborate the selective pyrolysis mechanistic interpretation of the externally excited (laser-driven) resonant response.

Original languageEnglish (US)
StatePublished - Jan 1 1999
Event37th Aerospace Sciences Meeting and Exhibit, 1999 - Reno, United States
Duration: Jan 11 1999Jan 14 1999

Other

Other37th Aerospace Sciences Meeting and Exhibit, 1999
CountryUnited States
CityReno
Period1/11/991/14/99

Fingerprint

HTPB propellants
pyrolysis
propellants
Pyrolysis
Propellants
combustion
laser
Lasers
lasers
Spontaneous combustion
vapor phases
spontaneous combustion
Peclet number
causes
thermocouples
Thermocouples
Gases
gas phase reaction
Binders
depletion

ASJC Scopus subject areas

  • Space and Planetary Science
  • Aerospace Engineering

Cite this

Hickman, S. R., & Brewster, M. Q. (1999). Laser-recoil response of AP-HTPB propellants (1-5 atm): Selective pyrolysis response. Paper presented at 37th Aerospace Sciences Meeting and Exhibit, 1999, Reno, United States.

Laser-recoil response of AP-HTPB propellants (1-5 atm) : Selective pyrolysis response. / Hickman, S. R.; Brewster, M. Q.

1999. Paper presented at 37th Aerospace Sciences Meeting and Exhibit, 1999, Reno, United States.

Research output: Contribution to conferencePaper

Hickman, SR & Brewster, MQ 1999, 'Laser-recoil response of AP-HTPB propellants (1-5 atm): Selective pyrolysis response', Paper presented at 37th Aerospace Sciences Meeting and Exhibit, 1999, Reno, United States, 1/11/99 - 1/14/99.
Hickman SR, Brewster MQ. Laser-recoil response of AP-HTPB propellants (1-5 atm): Selective pyrolysis response. 1999. Paper presented at 37th Aerospace Sciences Meeting and Exhibit, 1999, Reno, United States.
Hickman, S. R. ; Brewster, M. Q. / Laser-recoil response of AP-HTPB propellants (1-5 atm) : Selective pyrolysis response. Paper presented at 37th Aerospace Sciences Meeting and Exhibit, 1999, Reno, United States.
@conference{4ba909d9268d4f10962c96507f21acf5,
title = "Laser-recoil response of AP-HTPB propellants (1-5 atm): Selective pyrolysis response",
abstract = "The combustion of HTPB propellants containing fine AP was investigated using laser-driven, combustion recoil at [l to 5 atm. At 1 atm, binder-rich (70 to 75{\%} AP), monomodal fine-AP (2 to 50 μm) propellants exhibit a prominent secondary (non-QSHOD) laser-driven response peak at 100 to 300 Hz, with frequency varying inversely with AP size. Adding coarse AP (resulting in a wide, bimodal AP distribution) causes the secondary response to disappear at 1 atm. Raising the pressure to 2 atm causes the secondary response to reappear and increase in frequency to 600-800 Hz (2 μm AP). This oscillatory combustion behavior is attributed to time-varying selective or disproportionate pyrolysis of AP and HTPB, (unsteady accumulation and depletion of AP at the propellant surface) and the associated compositional (stoichiometric) fluctuations that occur in the fuel-rich, premixed gas phase reaction zone adjacent to the fine-AP/HTPB solid region. Low Peclet number appears to be a requirement of achieving this condition. Undriven combustion recoil and thermocouple measurements at 1 atm exhibited spontaneous combustion and gas phase temperature oscillations in the monomodal fine-AP propellants and corroborate the selective pyrolysis mechanistic interpretation of the externally excited (laser-driven) resonant response.",
author = "Hickman, {S. R.} and Brewster, {M. Q.}",
year = "1999",
month = "1",
day = "1",
language = "English (US)",
note = "37th Aerospace Sciences Meeting and Exhibit, 1999 ; Conference date: 11-01-1999 Through 14-01-1999",

}

TY - CONF

T1 - Laser-recoil response of AP-HTPB propellants (1-5 atm)

T2 - Selective pyrolysis response

AU - Hickman, S. R.

AU - Brewster, M. Q.

PY - 1999/1/1

Y1 - 1999/1/1

N2 - The combustion of HTPB propellants containing fine AP was investigated using laser-driven, combustion recoil at [l to 5 atm. At 1 atm, binder-rich (70 to 75% AP), monomodal fine-AP (2 to 50 μm) propellants exhibit a prominent secondary (non-QSHOD) laser-driven response peak at 100 to 300 Hz, with frequency varying inversely with AP size. Adding coarse AP (resulting in a wide, bimodal AP distribution) causes the secondary response to disappear at 1 atm. Raising the pressure to 2 atm causes the secondary response to reappear and increase in frequency to 600-800 Hz (2 μm AP). This oscillatory combustion behavior is attributed to time-varying selective or disproportionate pyrolysis of AP and HTPB, (unsteady accumulation and depletion of AP at the propellant surface) and the associated compositional (stoichiometric) fluctuations that occur in the fuel-rich, premixed gas phase reaction zone adjacent to the fine-AP/HTPB solid region. Low Peclet number appears to be a requirement of achieving this condition. Undriven combustion recoil and thermocouple measurements at 1 atm exhibited spontaneous combustion and gas phase temperature oscillations in the monomodal fine-AP propellants and corroborate the selective pyrolysis mechanistic interpretation of the externally excited (laser-driven) resonant response.

AB - The combustion of HTPB propellants containing fine AP was investigated using laser-driven, combustion recoil at [l to 5 atm. At 1 atm, binder-rich (70 to 75% AP), monomodal fine-AP (2 to 50 μm) propellants exhibit a prominent secondary (non-QSHOD) laser-driven response peak at 100 to 300 Hz, with frequency varying inversely with AP size. Adding coarse AP (resulting in a wide, bimodal AP distribution) causes the secondary response to disappear at 1 atm. Raising the pressure to 2 atm causes the secondary response to reappear and increase in frequency to 600-800 Hz (2 μm AP). This oscillatory combustion behavior is attributed to time-varying selective or disproportionate pyrolysis of AP and HTPB, (unsteady accumulation and depletion of AP at the propellant surface) and the associated compositional (stoichiometric) fluctuations that occur in the fuel-rich, premixed gas phase reaction zone adjacent to the fine-AP/HTPB solid region. Low Peclet number appears to be a requirement of achieving this condition. Undriven combustion recoil and thermocouple measurements at 1 atm exhibited spontaneous combustion and gas phase temperature oscillations in the monomodal fine-AP propellants and corroborate the selective pyrolysis mechanistic interpretation of the externally excited (laser-driven) resonant response.

UR - http://www.scopus.com/inward/record.url?scp=84983119766&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84983119766&partnerID=8YFLogxK

M3 - Paper

AN - SCOPUS:84983119766

ER -