A consortium of companies in Poland will investigate new fuel injector designs to improve variable thrust in rocket engines using storable ‘green’ propellants.
A contract was signed last week between ESA and Łukasiewicz Research Network – Institute of Aviation in Poland as prime contractor.
New injector and engine control valves will be designed, built and tested to better understand thrust control in a demonstration engine of a 5kN thrust class.
Firing the engine whilst varying the fuel and oxidiser input will change the thrust. This project will test various designs of a “pintle” injector to maintain stable combustion while testing a wide thrust range.
In addition, the project will incorporate new engine control valves and investigate low-cost prototyping and manufacturing methods such as additive layer manufacturing.
The Łukasiewicz Research Network – Institute of Aviation is the prime contractor working on the injector design, valve flow parts, overall demonstrator design and the demonstrator test at their onsite test benches.
Astronika will work on the valve control parts and overall control methods, Jakusz SpaceTech will provide high-grade hydrogen peroxide as the oxidiser for the tests, and advise on the handling of the fuels and oxidiser.
The demonstration engine uses hydrogen peroxide – an environmentally friendly alternative to nitrogen-tetroxide that is currently used on “storable” liquid propellant stages on launch vehicles.
Storable propellants are liquid at room temperature, unlike cryogenic propellants such as oxygen and hydrogen, which must be kept very cool. Rocket engines that are powered this way are easy to ignite reliably and repeatedly on missions lasting many months.
Synergies with other ongoing ESA projects in this domain, such as continuations of the storable engine demonstrator, Small Scale Combustion Chamber with ArianeGroup in Germany, mean that such projects can be integrated in the future for a complete low-cost throttleable green engine design.
The technologies proved in this project could be used in launch vehicle kick-stages to enable more flexible missions, in microlauncher upper stages, and for future space exploration using lunar or planetary descent vehicles. This engine could also be implemented on reusability demonstration platforms, working towards the landing of launcher stages.
These activities are being carried out within ESA’s Future Launchers Preparatory Programme to further our understanding of ecological propellants and associated propulsion technologies.