Determination of Burn Rate Equation Uncertainty Intervals in Solid Fuel Ramjet

As part of an ongoing research program, the Propulsion Research Center at the University of Alabama in Huntsville is evaluating fuel formulations for use in a solid fuel ramjet combustor. Assessment of the burning rate for the propellant and the burn rate equation was conducted for a set of tests of a single formulation. The uncertainty in the calculated burn rate for each test and the uncertainty of burn rate equation fit to these data were estimated through a Monte Carlo Routine. Uncertainties for the average burn rate from individual tests ranged from 7.6% to 8.3% and the burn rate equation was found to have a lower uncertainty around 4.5%. This paper outlines the process used to determine the uncertainty of the burn rate and burn rate equation.