Hypergolic Ignition Investigations with an Impinging Injector of an Ionic Liquid Fuel with Hydrogen Peroxide

Abstract

Conventional hypergolic propellants as e.g. MMH/NTO are highly toxic. Therefore, research is conducted to find suitable, less toxic propellant candidates as replacement. At DLR a hypergolic propellant combination comprised of highly concentrated hydrogen peroxide and an ionic liquid, so-called HIP_11, was identified and the hypergolic ignition was verified with drop tests. In the present investigation, first results of the hypergolic ignition of HIP_11 under flowing conditions are presented. A 2-on-1 impinging jet injector was designed, manufactured and tested in a dedicated hypergolic ignition test setup. The ignition was studied underdifferent injection conditions. The average ignition delay time ranged between 7.8 ms and 4.9 ms depending on the operating point. Also, a continuous combustion over a wide range of operating conditions was observed. As a result, HIP_11 is able to produce fast and reliable hypergolic ignitions and to sustain the combustion. Therefore, it is a very promising candidate for the substitution of conventional hypergolic propellants.