Preliminary Assessment of Hydrogen Peroxide Gel as an Oxidizer in a Catalyst Ignited Hybrid Thruster

Abstract

In regard to propulsion system applications, the stability of liquid propellants in long-term storage is of increasing importance, and this had led to a greater interest in gelation technology. As part of a preliminary test to determine the feasibility of using a gel propellant in a rocket with a catalyst bed, a hybrid rocket with a catalyst reactor using a gel propellant as an oxidizer was tested for the first time in this study. Experiments were conducted with two different oxidizers: one with liquid phase hydrogen peroxide and the other with gel phase hydrogen peroxide, as well as high-density polyethylene as fuel for a 250 N class hybrid thruster performance test. The thruster was designed with the catalyst ignition system, and a catalyst was manufactured to be inserted into the catalyst reactor to facilitate oxidizer decomposition. While the test result with neat hydrogen peroxide indicated sufficient decomposition efficiency using a manganese dioxide/alumina catalyst and successful autoignition of the fuel via the decomposed product, gel hydrogen peroxide exhibited insufficient decomposition and there were difficulties in operating the thruster as a part of the catalyst was covered in the gelling agent. This preliminary study identifies the potential challenges of using a gel phase oxidizer in a catalyst ignited hybrid thruster and discusses the technical issues that should be addressed in regard to a gel propellant hybrid thruster design with a catalyst reactor.

Linear instability analysis of a shear thinning gelled jet with yield stress in coaxial atomization

“…In addition, gel propellants are sensitive to the geometry of the supply line, leading to their high requirements for the pipeline design. 11,12 Since the atomization of gel propellants is directly related to combustion efficiency and engine performance, which further affect the propulsion performance, effectively improving the atomization performance of gel propellants has been the subject of numerous aerospace academics.…”

“…7 Gel, which offers the dual advantages of liquid and solid, 8 has been paid much attention in innovative aerospace engineering as a new type of storable propellant. 9–11 A gel propellant not only inherits the characteristics of high specific impulse and multiple starting and adjustable thrust of a liquid propellant but also has the merits of a solid propellant such as uneasy leakage, long-term storage and easy maintenance. 12…”

“…7 Gel, which offers the dual advantages of liquid and solid, 8 has been paid much attention in innovative aerospace engineering as a new type of storable propellant. [9][10][11] A gel propellant not only inherits the characteristics of high specific impulse and multiple starting and adjustable thrust of a liquid propellant but also has the merits of a solid propellant such as uneasy leakage, long-term storage and easy maintenance. 12 A gel propellant, which is a liquid-like mixture with rheological properties, is formed by adding a certain amount of gelling agent (gellants) into the liquid propellant base, providing a complex behavior of non-Newtonian fluids for the propellant.…”