3D Printing Complete Rocket Engine from the 3D Printer
ESA manufactured a complete rocket engine in a 3D printer. This engine has now been successfully tested by the DLR (German Aerospace Center). 3D printing could accelerate space travel enormously.
Berta was completely manufactured by 3D printing processes and has now completed the first successful test on the P8 test bench in Lampoldshausen. Berta stands for "Biergoler space transport drive" and is a rocket engine.
Berta is designed for a reference thrust of 2.45 kilonewtons and could be tested on the test bench for 560 seconds - an important milestone for the European Space Agency ESA. The engine was developed within the framework of research for future European carrier systems of ESA.
Multiple Ignition Engine for Extended Missions
Berta is designed for operation with storable fuels. This means that the fuels can be stored at room temperature. Engines of this type can be ignited very reliably and repeatedly and are therefore suitable for extended missions. This means that this engine can be used not only for near-earth missions on small to medium-sized rockets, but also for missions beyond Earth orbit. However, common storable fuels are highly toxic. Cryogenic fuels, i.e. liquefied gases, are used for the test runs on the test bench.
The head of the test bench P8 Gerd Brümmer explains: "The aim of the current tests is to investigate the flow behavior and heat transfer of printed surfaces. At present, in Europe this new technology can only be tested on Test Stand 8 in Lampoldshausen."
Manufacturing Engines within a Few Weeks
3D printing provides various advantages for engine construction. In this way, production times can be significantly reduced. At present, for example, combustion chambers are cast and forged first. Cooling channels are then milled out and covered by galvanic processes. Usual delivery times are up to one and a half years. By means of additive manufacturing, on the other hand, complete engines can be delivered within a few weeks.
In the case of Berta, both the injection head - consisting of a corrosion-resistant nickel-based alloy - and the combustion chamber made of stainless steel were manufactured by selective laser melting using the 3D printing process. Using a laser, the final component was applied layer by layer by melting the material in powder form onto a base plate.
3D Printing Enables More Complex Structure
In addition, more complex structures can be produced using the 3D printing process, which cannot be produced in conventional processes. For example, Berta contains a complex design for the cooling channels, which is intended to ensure improved cooling behavior of the combustion chamber. Thanks to improved cooling, combustion chambers can be made more compact in the future, which saves material.
The test campaign will last another four weeks and the results will also be integrated into further ESA development projects. For example, 3D printing processes are to be used for further developments of the Ariane 6 engines Vinci and Vulcain.
This article was first published by Konstruktionspraxis.
Original: Katharina Juschkat / Translation: Alexander Stark