Investigation of the effects of solid rocket motor propellant composition on plume signature
Snaza, Clay J.
Netzer, David W.
Newberry, Conrad F.
MetadataShow full item record
Three propellants with aluminum/silicon weight percentages of 18/0%, 13.5/4.5%, and 12/6% were fired in a subscale motor to determine if the plume infrared signature could be reduced without a significant loss in specific impulse. Spectral measurements from 2.5 to 5.5 micrometers and thermal measurements from 3.5 to 5.0 micrometers were made. Plume particle size measurements showed that only particles with small diameters (less than 1.93 micrometers) were present with any significant volume. Replacing a portion of the aluminum in a highly metallized solid propellant with silicon was found to eliminate the Al2O3 in favor of SiO2 and Al6SiOl3, without any change in particulate mass concentration or any large change in particle size distribution. These particulates were found to have significantly lower absorptivity than Al2O3. An additional investigation was conducted to determine the particle size distribution at the nozzle entrance. Malvern ensemble scattering, phase-Doppler single particle scattering and laser transmittance measurements made through windows in the combustion chamber at the nozzle entrance indicated that large particles were present (to 250 micrometers). However, most of the mass of the particles was contained in particles with diameters smaller than 5 micrometers. Approximate calculations made with the measured data showed that if 100 micrometers particles are present with the smoke (particles with diameters less than 2 micrometers) they could account for only approximately 10% of the article volume
Approved for public release, distribution is unlimited
Showing items related by title, author, creator and subject.
Yakin, Bulent (Monterey, California. Naval Postgraduate School, 1993-12);An investigation was conducted using a subscale solid rocket motor to measure the effect of nozzle residence time on the behavior of Al203 particles to assess the applicability of subscale motor data to full-scale motors ...
Manser, John R. (Monterey, California. Naval Postgraduate School, 1995-03);An experimental investigation to measure particle size distributions in the plume of sub-scale solid rocket motors was conducted. A phase-Doppler particle analyzer (pDPA) in conjunction with three-wavelength extinction ...
Racine, John A. (Monterey, California. Naval Postgraduate School, 1991-12);A combined optical and particle collection probe which employed an in situ particle size distribution measurement method and an infrared camera were used to obtain data that could be used to validate solid propellant ...