Physical and ballistic characterization of AlH3-based space propellants

Spectroscopic and structural investigations of α‐, β‐, and γ‐AlH3 phases

“…[1,2] Such high hydrogen content makes aluminum hydrides particularly suitable for hydrogen storage. In addition, its highly exothermic combustion, which is an advantageous characteristic for any propellant compound, combined with its metal oxidation and low molecular weight, makes aluminum hydride an excellent candidate for rocket propulsion, especially in upper-stage motors, where low weight is most desirable.…”

“…[2,3] Such an increase in optimum performance is possible because of this metal hydride fuel's low-ignition temperature of 1450 K and low-combustion temperature of 3391 K. Indeed, alane has a higher initial burning rate as compared with that of pure aluminum, which ignites at around the alumina melting point and combusts at 3716 K. [2] On the other hand, use of aluminum hydride presents several disadvantages: (1) the colorless solid material reacts violently with water and atmospheric moisture, [4] (2) it has low chemical and thermal stability, and (3) it is sensitive to friction. [2] The decomposition of alane as well as its reactivity with air [5] generates excessive amounts of hydrogen gas during storage. [6] The material is unstable under ambient pressure and temperature and the layered structure of alternating planes of aluminum and hydrogen is believed to facilitate the release of H 2 gas.…”

Literature survey for a first choice of a fuel-oxidiser couple for hybrid propulsion based on kinetic justifications

“…Among these additives, alane (AlH 3 ) seems promising because it increases the Isp and reduces the throat erosion [67,68]. Other types of fuels are considered, such as silane (Si n H n+2 ), because they present higher specific impulse [69].…”

Problems in studying formation of smoke oxide particles in combustion of aluminized solid propellants

“…We can mentioned several papers where the results allow the authors to argue definitely that this phenomenon does occur (e.g., [20,21]). This temperature was quantified for the first time as applied to conditions of combustion within the propellant by Russian scientists [22]: ≈1300 K. Obviously, depending on the properties of the propellant and initial metallic fuel, the ignition temperature of the latter may slightly vary [1,23].…”