CO₂ laser-induced combustion of ammonium dinitramide (ADN)

Experimental studies of CO₂ laser-induced combustion of ammonium dinitramide (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/cm². Quantitative gaseous species measurements obtained by microprobe sampling and mass spectrometer analysis are presented in the form of spatial and temporal profiles. Both gas-phase temperature profiles and surface temperatures measured with fine-wire thermocouples are given. 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 testing: laser-induced pyrolysis, laser- induced regression, and laser-assisted combustion. The physical, thermal, and chemical characteristics of these three regimes are described.