| Results from fifteen static test firings of lab scale hybrid rocket motors utilizing 90% concentrated hydrogen peroxide as an oxidizer with hydroxyl terminated polybutadiene fuel are presented. Thirteen of those tests utilized aluminum or aluminum/magnesium alloy additive in the fuel. The performance characteristics of the propellant combinations were determined. The experimental results indicated combustion efficiencies of 72%--90%, and regression rates on the order of 1 mm/s for the metallized fuel combinations. A correlation of the regression rate data for the metallized propellants deviated from that which was expected for turbulent convective heat transfer dominated behaviour, indicating a possible sensitivity of the metallized propellant combinations to chamber pressure. A numerical model of the hydrogen peroxide/non-metallized hydroxyl terminated polybutadiene motor was built in a commercial computational fluid dynamics code, CFX 5.7.1. The model was combined with a FORTRAN code that was developed at Carleton University, to predict the regression rate of the propellant combination at the initial operating conditions for two of the experimental tests. The predicted spatially averaged regression rates agreed with the measured spatially and temporally averaged regression rates to within 6% and 10% respectively. |
