CO2 LASER-INDUCED COMBUSTION OF AMMONIUM DINITRAMIDE (ADN)

Experimental studies of CO2 laser-induced combustion of ammonium dinit ramide (ADN) were performed to determine the key physical and chemical processes involved. Experimental conditions covered the range of 0.1- 5.0 atmospheres in argon and incident laser heat fluxes of 20 to 300 W /cm(2). Quantitative gaseous species measurements obtained by micropro be sampling and mass spectrometer analysis are presented in the form o f spatial and temporal profiles. Both gas-phase temperature profiles a nd surface temperatures measured with fine-wire thermocouples are give n. Observations made with a high-magnification video recording system and Schlieren photography of the physical phenomena involved are also discussed. Three distinct regimes of behavior were identified during t esting: laser-induced pyrolysis, laser-induced regression, and laser-a ssisted combustion. The physical, thermal, and chemical characteristic s of these three regimes are described. (C) 1998 by The Combustion Ins titute.