Ballistic and thermomechanical characterisation of paraffin-based hybrid rocket fuels loaded with light metal hydrides

Atomic insights into combustion mechanism of nano‐aluminum hydride

“…As the reaction progresses, the core AlH 3 is gradually dehydrogenated and transform to aluminum cluster. These results indicate that the release of H 2 is accompanied by the formation of aluminum nuclei, which is consistent with the experimental results 24 . The amount of H 2 in the gas cavity is gradually increased, the small chambers gradually merge into a larger one, and the external oxide layer is continuously expanded and thickened.…”

“…These results indicate that the release of H 2 is accompanied by the formation of aluminum nuclei, which is consistent with the experimental results. 24 The amount of H 2 in the gas cavity is gradually increased, the small chambers gradually merge into a larger one, and the external oxide layer is continuously expanded and thickened. The uneven diffusion of aluminum in the inner core leads to different pressure in the internal hydrogen gas chambers.…”

“…[17][18][19][20][21][22] These light metal hydrides have been widely used in the energy field especially in energetic materials due to their superior hydrogen storage density and high reactivity. 23,24 AlH 3 is a covalently bonds, metastable solid at room temperature with a large gravimetric and volumetric hydrogen capacity (10.1 wt% and 149 kg/m 3 , respectively), which is twice as much as the value of liquid hydrogen (0.070 g/mL); it has the rapid low-temperature decomposition kinetics (below 100 C). 25,26 It was first synthesized by Stecher and Wiberg as an impure solid.…”

“…Among metal hydrides, the light metal hydrides represented by aluminum hydride (AlH 3 ), magnesium hydride (MgH 2 ), and lithium hydride (LiH) have higher hydrogen content 17‐22 . These light metal hydrides have been widely used in the energy field especially in energetic materials due to their superior hydrogen storage density and high reactivity 23,24 . AlH 3 is a covalently bonds, metastable solid at room temperature with a large gravimetric and volumetric hydrogen capacity (10.1 wt% and 149 kg/m 3 , respectively), which is twice as much as the value of liquid hydrogen (0.070 g/mL); it has the rapid low‐temperature decomposition kinetics (below 100°C) 25,26 .…”

Thermal, Viscosimetric and Thermomechanical Combined Assessment of Mixture Modelled Composite Fuels for Hybrid Propulsion

“…It yielded a 3.55 cm length, a 6.51 cm and 2.69 cm external and internal diameters, respectively, as well as a volumetric contraction of 9.58 %, comparable to that of pure paraffin prepared under the same method, i. e. 9.90 % [19]. In addition, its mass amounted to 89.29 g, thus allowing a 9.73 % theoretical porosity, also comparable to the 11.33 % figure for pure paraffin, both attained in a centrifugal casting process, without vacuum application, and thus significantly higher than the ones found in other studies [44, 45]. This result seems coherent with the decrease in volumetric contraction stemming from centrifugal casting in pure paraffin, as compared to static casting data [19].…”