The goal of this research is to obtain experimental information about combustion characteristics of the composite propellant containing various metallic fuels. The propellant formulations contained two fractions of ammonium perchlorate (64.6%), inert binder (19.7%) - butadiene rubber SKD plastized with transformer oil, and metal fuel (15.7% of aluminum ASD-4, ASD-6, Alex; boron; aluminum diboride; aluminum dodecaboride; some mixtures of above listed ingredients). Experimental information will be used further as a background to develop the physical and mathematical model of combustion process.
Today’s fast breeder reactors contain mixed uranium —plutonium oxide fuel and are cooled with liquid sodium. Their normal operational behaviour, including power transients, is similar to that of thermal reactors. The fact that the sodium density coefficient is positive is of no importance at normal operating temperatures because negative coefficients like Doppler or fuel expansion coefficients have compensating effects. Dangerous effects may arise when sodium boiling at much higher temperatures occur. It is shown that sodium boiling in most cases can be avoided by proper design of the reactor core. Energy releases associated with partial destruction of the core are discussed. The safety features of metallic fuel are briefly discussed, resulting in the statement that in principle, use of metallic fuel does not promise more positive safety features.