Modeling and Diagnostics of Gel Propellant Mixing and Combustion

"In Phase I, CFDRC demonstrated a one-of-a-kind transient bipropellant spray combustion modeling capability for gel propulsion. A single element spray rig was fabricated and tested with inert gels to qualitatively characterize the gel spray pattern for thenumerical simulations. CCD photography and planar laser illumination (PLI) diagnostics techniques were demonstrated. A comprehensive plan for gel mixing and combustion diagnostics and modeling was formulated.In Phase II, a combination of diagnostic techniques will be utilized to enable wide-ranging vision into both vortex and pintle-type gel motors combustion. Measurements will include: spray density and distribution, gas temperature and combustion productspecies. The diagnostics techniques will be set up and refined at the University of Alabama in Huntsville followed by delivery to AMCOM. Continuous diagnostics engineering support during the testing of live propellants will be the key component to PhaseII success. A single high-quality laser and CCD camera system will form the core of conventional diagnostic approaches for flow visualization and Raman scattering (temperature and species) of both in-chamber and plume flow fields. A highly innovativein-chamber temperature mapping system based on passive and emissive acoustic tomography will be demonstrated within both vortex and pintle motors. Concurrent CFD code enhancements will include: chemical kinetics; droplet tracking