The development of an optically active laser schlieren system with application to high pressure solid proellant combustion

A laser schlieren system, using an optically active quartz prism-polaroid sheet combination aperture in place of the conventional knife edge, was developed and applied to high pressure solid propellant combustion studies. Advantages and limitations of the system are discussed. Ammonium perchlorate deflagration was observed to pressures of 2200 psi. Distant surface reaction sites were evidenced at high and low pressures by alternating density gradients in the gas across the deflagrating surface. These sites were found to be very small or nonexistent at intermediate pressures.