Solid-fuel ramjets (SFRJs) have received significant interest due to their high specific and density-specific impulse, simple and compact geometry, and maneuverability. The development of an experimental SFRJ capable of operating at up to 5 Ibm/s of non-vitiated heated air at ≤1500 F and a mean chamber pressure of 200 psia is reported. The experiment facilitates detailed analysis of flammability limits, regression rate, and combustion efficiency over a range of free-stream Mach numbers (2-4.5) and flight altitudes up to 80000 ft. Representative results that highlight operability of the experiment at air mass flow rates of 1.5 - 3.5 Ibm/s and mean combustion pressure of 75-165 psia at inlet air temperature of 480 - 630 °F, are presented. For these tests, the maximum reported axial thrust is up to 480 Ibf with corresponding l_(sp,R) of 120 s. Typical regression rates observed in the tests are between 0.030-0.075 in/s. Estimation of convective and reaction kinetic time-scales indicate the combustion is limited by the chemical kinetics of fuel pyrolysis and oxidation for the current geometry and operating conditions.
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