With 3D-printed Rocket Engine Into Space

2023 Author : Hannah Pearcy | [email protected] . Last modified: 2023-06-01 01:49

To launch small satellites with a payload of up to 350 kg into space, you don't need an entire launcher. So-called microlauncher are a good alternative. To save more fuel, researchers at the Fraunhofer Institute for Material and Beam Technology IWS, together with space experts from the TU Dresden, have additively developed, manufactured and tested a new rocket engine. The new aerospike engine is said to save considerable weight and fuel

The special feature of the new aerospike engine: the fuel injector, combustion chamber and nozzle are produced layer by layer using Laser Powder Bed Fusion (L-PBF), an additive manufacturing process. The nozzle itself consists of a spiked central body, through which the combustion gases are accelerated.

Additive manufacturing makes efficient engines possible

The technological conception of the aerospike engines originated in the 1960s. "But only through the freedom of additive manufacturing and embedding it in conventional process chains is it possible for us to manufacture such efficient engines at all," says Michael Müller, research assistant at the Additive Manufacturing Center Dresden (AMCD), jointly developed by Fraunhofer IWS and TU Dresden is operated.

Michael Müller, research associate AMCD

Aerospike rocket engines promise fuel savings of around 30 percent compared to conventional rockets. In addition, they are more compact than conventional systems, which reduces the mass of the overall system. Mirco Riede, Group Leader 3D Generating at Fraunhofer IWS, explains: “In space travel, every gram of gold saved is worth it because you have to take less fuel into orbit. The heavier the overall system, the less payload can be transported.”The aerospike nozzle adapts better to the pressure conditions on the way from Earth to orbit. This makes it more efficient and uses less fuel than conventional engines.

How the engine was made

When manufacturing the rocket, the researchers opted for additive manufacturing because the engine requires very good cooling and internal cooling channels. "This complex regenerative cooling system with intricate, intricate structures cannot be milled or cast conventionally," explains Riede.

The powder is applied layer by layer and then selectively melted by laser . This gradually creates the component, including the one millimeter wide cooling channels that follow the contour of the combustion chamber. The powder is subsequently sucked out of the channels. The requirements for the metal: It must be solid at high temperatures and be able to conduct heat well to ensure optimal cooling, because temperatures in the combustion chamber will be several thousand degrees Celsius.

3D printing

Complete rocket engine from the 3D printer

Prototype successfully tested

The manufacture of the injectors places particularly high demands on design and manufacture. Müller explains the process of thrust development: "The fuels are first used to cool the engine, they heat up and are then introduced into the combustion chamber." Liquid oxygen and ethanol are fed in separately and combined using an injector. The resulting gas mixture is ignited. It expands in the combustion chamber, then flows through a gap in the combustion chamber and is expanded and accelerated via the nozzle.

The Dresden researchers have already tested the prototype of the aerospike engine on the test stand of the Institute of Aerospace Technology at the TU Dresden. They achieved a burn time of 30 seconds. "This is a special process, because there are hardly any tests of aerospike nozzles yet," says Müller. "We have demonstrated that additive manufacturing can produce a functioning liquid engine."

At the Hannover Messe, visitors can see the rocket engine in Hall 16 at Stand C18 .

Seminar tip

The 3D printing seminar in direct digital production conveys the technology, suitability and requirements of 3D printing and gives the participants an overview of the developments, possibilities and limits.

costs