High-pressure strand burner system for propellant flame studies using absorption spectroscopy

The design and operation of a high-pressure strand burner capable of withstanding pressures up to 6.9 MPa are described. The associated components for use with the chamber, which is employed to study the combustion behavior of solid propellants burning at a constant pressure, are specified. By using this design, it is possible to perform absorption measurements through the flame zone with a line-of-sight that is free from the effects of recirculating product gases. Absorption measurements using Fourier-transform infrared spectroscopy are performed during the combustion at a spatial resolution of approximately 1 mm. The obtained spectra are of sufficient signal-to-noise ratio to allow a determination of species concentration and temperature profiles. Such data are of utmost importance for the elucidation of the complex chemical kinetics of solid propellant ignition and combustion.