The market for small satellites is expected to boom in the coming years. Great Britain is planning the first spaceport on European soil in the north of Scotland, and Germany is also mulling the construction of a launch site. From there, small to medium-sized rockets will carry research instruments and small satellites weighing up to 350 kg into space. An efficient way to propel these microlaunchers are so-called aerospike engines. These not only offer the prospect of a considerable reduction in mass, but also a significant saving in fuel.
A research team of the TU Dresden and the Fraunhofer Institute for Material and Beam Technology IWS has now developed, manufactured and tested such an aerospike engine. The special feature: Fuel injector, combustion chamber and nozzle are manufactured layer by layer by 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.
Although the technical concept of aerospike engines is already around 60 years old, it is only the additive manufacturing process with its high degree of design freedom as well as the embedding of this technology in conventional process chains that makes it possible to build such engines. Aerospike rocket engines promise fuel savings of around 30 percent compared to conventional rockets. They are also more compact and lightweight than conventional systems.