Boron-loaded gel fuel as potential fuel for ramjet and scramjet engines- recent advancements

Abstract

Boron, a high-energy metalloid has been recognized as a potential secondary energy source for liquid hydrocarbon fuel to power volume-limited propulsion devices such as ramjet and scramjet. The higher volumetric and gravimetric energetic content makes boron a more suitable candidate than other energetic particles. The stability of the particle is one of the significant drawbacks of adopting metal particles in liquid fuel, which gel fuels can overshoot. Though several works have been published on metalized and non-metalized gel fuels, studies focusing on boron-loaded gel fuels are scarce. The present work comprehensively reviews recent advancements and challenges in adopting boron-loaded gel fuel for practical ramjet and scramjet propulsion devices. It mainly encompasses the formulation of boron-loaded gel fuel, rheological behavior and its influencing factors, single droplet combustion characteristic, spray characteristics, spray combustion characteristics, and the effect of boron-loaded gel fuel on the performance of practical ramjet and scramjet combustors.