Accession Number:

ADA037252

Title:

Experimental Results for Hydrocarbon Exhaust Infrared Model Verification.

Descriptive Note:

Final rept. Jul 75-Mar 76,

Corporate Author:

AIR FORCE ARMAMENT LAB EGLIN AFB FLA

Report Date:

1976-07-01

Pagination or Media Count:

128.0

Abstract:

The objective of this effort was to evaluate a number of computer models used to predict infrared characteristics of hydrocarbon exhaust plumes. This report contains the experimental results obtained. Controlled plumes were generated using a small rocket operating at approximately 4 atmosphere chamber pressure and 5 grams per second total mass flow rate, exhausting into a large chamber held at 13.1 kilometers, static altitude conditions. Two liquid and two gaseous fuels were burned with gaseous oxygen at mixture ratios from 1.2 to 8.4. Engine performance was monitored with respect to combustion efficiency. Plume spatial radiation distributions were measured normal to the exhaust centerline by a scanning radiometer operating in the 4.1-to 5.1-micrometer band. Plume spectral radiation distributions were measured in a spot on the on the plume centerline by an interferometer spectrometer operating in the 2- to 5-micrometer region. These results show that the degree of plume afterburning with the ambient air is the dominant factor controlling hydrocarbon exhaust infrared intensity in the 4.0- to 5.5-micrometer band. Mixture ratio, combustion efficiency, and propellant composition are the key parameters affecting plume afterburning processess. These data should provide a good basis for comparison with predicted results over a sufficiently broad range of conditions to allow thorough model verification and identification of model deficiencies. Author

Subject Categories:

  • Infrared Detection and Detectors
  • Liquid Propellant Rocket Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE