Modeling and Experiments of Laser-Induced Ignition of Nitramine Propellants

Abstract

The objective of the work is to develop and experimentally verify a model for CO2 laser-induced ignition of nitramine-based propellants. The one-dimensional model considers heat conduction in the condensed-phase coupled to heat and mass transport with global chemical kinetics of a heterogeneous propellant in the gas-phase region. The highly nonlinear model was solved numerically. Experimentally, increases in heat  ux [125– 375 W/cm (193– 578 cal/s-in.)] lowered the ignition delay time, but changes in pressure [1.38–3.79 MPa (200–550 psia)] had very little effect. This supports the assumption that cyclotrimethylenetrinitramine decomposition is primarily temperature controlled. These trends are correctly predicted by the model. Predictions of ignition delay time match the experimental data within the measurement uncertainty. Sensitivities of the numerical solution to the material properties and kinetic rate constants are addressed.