Combustion of aluminum and boron agglomerates free falling in air. I. Experimental approach

This paper presents a review of studies of the combustion of composite propellants containing a fuel based on aluminum and boron. A method for studying the combustion of large particles of a combined $\mathrm{Al}+\mathrm{B}$ fuel in air is presented. Burning $\mathrm{Al}/\mathrm{B}$ particles $300$–$700$ $\mu$m in diameter of agglomeration origin were obtained by ignition of miniature pieces of a mixed composition containing $32\%$ binder and $68\%$ micron size aluminum and boron powders in the ratio $\mathrm{Al}/\mathrm{B}=81/19$ placed in a burning metal-free sample. Agglomerates formed by the merger of many small particles burned in free fall in air. The procedures for processing video records of the combustion process and studying condensed combustion products (residues of burning agglomerates) to determine the burning time and analyze the transformation of the combined fuel into oxide are described.