Hypergolic Ignition of Lithium–Aluminum–Hydride-Doped Paraffin Wax and Nitric Acid

摘要

Analytical reagent (AR)-grade nitric acid (69.3% by mass) and lithium–aluminum–hydride (LAH) as an additive toparaffin wax are evaluated as green propellant substitutes for state-of-the-art propellants currently used for in-spacepropulsion. The viabilities of hypergolic ignition and ignition delay (ID) times were measured for a range ofconditions, including LAH loading in paraffin and ignition test chamber pressure. A strong inverse trend betweenID and pressure was observed for the reaction of AR-grade nitric acid and pure LAH. A minimum of 50% massloading ofLAHin paraffin wax was required for reliable hypergolic ignition with AR-grade nitric acid at atmosphericpressure under a pure nitrogen environment.