Combustion dynamics of organic-gellant-laden ethanol fuels

Abstract

Modern-day aerospace propulsion systems are scaling new heights of innovation in technology and performance. Alongside performance, parameters like reusability, ease of processing, reliability, and ecological safety of fuel sources are of prime concern. Gelled propellants have the potential to replace conventional solid and liquid fuels by integrating their benefits and concurrently negating their disadvantages, therefore they are considered promising candidates for hybrid rocket and ramjet propulsion systems. The liquid propellant is widely used as either a mono or bipropellant. It is pumped/fed under pressure and an atomization system is used to spray the liquid into the combustion chamber. Thus, ease of throttle control makes liquid propellants superior to solid propellants, but they have their inherent drawbacks. A major issue to be considered with all the classes of liquid propellants is sloshing in the storage tanks. Another major disadvantage of the typical liquid propellants is the likelihood of leakage and spills during handling, this becomes a key concern specifically in the case of hazardous hypergolic liquids. Modern-day high-performance and energy-dense cryogenic liquid propellants have their utility, but they are more difficult to handle and suffer from high evaporation losses, embrittlement of the storage vessel, and difficulty in storage under zero gravity.