Experimental Investigation of Combustion Performances of a Green Hypergolic Bipropellant based on Hydrogen Peroxide

Abstract

The present study examines the advancement of a promising low-toxicity hypergolic propellant combination called HIP_11 for in-space applications, developed as alternative to common toxic propellants. The fuel is an Energetic Ionic Liquid, storable, stable and simple to handle at ambient conditions, developed at the Institute of Space Propulsion, German Aerospace Centre (DLR). The compound shows hypergolicity behaviour when in contact with Hydrogen Peroxide and is a promising substitution to typical propellants. The present work describes the advancements in the development of HIP_11 through a dedicated experimental campaign, consisted in more than 50 successful firings, analysing and investigating the performances. The experiments are based on a small modulable thruster that allowed to study the efficiency and stability of combustion of the propellant combination while varying various design parameters of the thruster. Specifically, the effects of different injector designs, as well as variations in combustion chamber shape, characteristic length, and operating pressure have been thoroughly examined and analysed.