Synergistic Enhancement of Heat Sink and Combustion Performance of Boron-Based Phase-Change Nanofluid Fuels for Scramjet at Higher Mach Numbers

Endothermic high-energy nanofluid fuels represent a novel fuel type with great potential to address the overheating and thrust deficiency issues of scramjet engines under high Mach number. Boron features a high combustion calorific value, yet its lack of catalytic cracking activity renders it difficult to be directly used as an additive for endothermic nanofluid fuels. Herein, we first report a strategy of confined molecular phase change and boron nanoparticles catalysis for nanofluid stability and enhancement of physical and chemical heat sink. Boron nanoparticles with catalytic activity (NBK, nano-boron KH550) are obtained through ultrasound-assisted in situ surface functionalization treatment. The oxidation degree and calorific value of NBK were enhanced by 3.6