RT Journal Article
ID 15586a9a54ad0338
A1 Risha, Grant
A1 Koch, Donald E.
A1 Harvel, James R.
T1 LASER IGNITION CHARACTERIZATION OF N-5 DOUBLE-BASE SOLID PROPELLANT
JF International Journal of Energetic Materials and Chemical Propulsion
JO IJEMCP
YR 2002
FD 2002-01-01
VO 5
IS 1-6
SP 284
OP 295
K1 energy flux
K1 radiative heating
K1 ignition
K1 solid propellant
K1 combustion
K1 double base propellant
AB An experimental investigation of the ignitability of various material lots of N-S double-base solid propellant has been conducted. In order to investigate an observable variance in the ignition stages of the N-5 solid propellant lots (EP-A, EP-B, and EP-C), the ignition behavior (including the onset of initial gas evolution, first light emission, and self-sustained ignition) was determined. Original ring-shaped N-S propellant samples were cut into eight equal samples, inserted into the sample holder, and ignited using the radiant heat flux of a high-powered CO2 laser, which produces an infrared laser beam at a wavelength of 10.6 μm. For each test run, the sample was carefully placed in a specially designed carbon-carbon (graphite) sample holder. This laser power delivered to the propellant surface corresponds to the radiative heat flux ranging from 29 to 61 W/cm2. The CO2 laser shutter was set to the calculated for the two raw material lots of N-5 (EP-A and EP-B). The materials lots manufactured in 1984 (EP-B) were found to have more reproducible experimental results. For the 1990 material lots (EP-A), there was less condensed-phase residue after the test ran. The energies supplied from the laser to initiate gas evolution and first light emission from the propellant surface agreed well between both older and newer raw material propellant lots. However, the ignition delay time (tIGN) for the newer N-5 lot is much longer than that of the older N-5 lot. This implies that the thermal pyrolysis induced fragmented species from these two lots are much different. Also, the dependency of tIGN on heat flux had opposite trends. The recovered N-5 propellant sample (EP-C) from a failed gas generator test ran showed a prolonged ignition delay period. The data obtained from six equal segments of a single ring exhibited severe scattering in the measured tIGN. This implies that the material is non-uniform due to exposure to the hot product gases and condensed-phase particles from the Triple Six booster charge.
PB Begell House
LK https://www.dl.begellhouse.com/journals/17bbb47e377ce023,76f8e14974df93a8,15586a9a54ad0338.html