Investigation of fuel-rich boron combustion in a pressurized combustion bomb

Small pellets of two different fuel-rich boron propellants were burnt in a pressurized combustion bomb in order to investigate the combustion in ducted rocket primary combustion chambers. The pressure varied between 1 and 100 bar. The combustion products were chemically analyzed for boron, boron oxide, and boron carbide. The results were plotted versus pressure and compared with computed equilibrium compositions. The main conclusion is that considerable extent of boron conversion into reaction products is already taking place in the primary gas generator of a ducted rocket.