Australian Students 3D Print a Rocket Engine and Win an International Competition

A team of University of Melbourne students has won an international rocketry competition with a liquid rocket engine that was largely built using metal 3D printing. Nicknamed Slinky, the engine is the first regeneratively cooled liquid bipropellant engine ever successfully fired by an Australian student team at Race2Space.

The three-person team, Jack Gardiner, Brooke Doolan, and Stuart Davis, developed the engine as part of their master's capstone project through the University of Melbourne Aerospace and Rocket Engineering Society. They worked alongside researchers at CSIRO's Lab22, Australia's national additive manufacturing innovation centre.

The key to the design is internal cooling. Traditional rocket engines rely on complex external pipework to keep the combustion chamber from melting. Using a Nikon SLM Solutions 280 2MA laser powder bed fusion system at Lab22, the team printed the chamber in a copper alloy with tiny cooling channels built directly into the wall. That approach is only possible with additive manufacturing.

Slinky weighs about six kilograms and produces a maximum thrust of 5.4 kilonewtons. At the competition in the United Kingdom, it completed five hot-fire tests in one day, including throttling runs, and took first place in the LOX bipropellant category.

Dr Cherry Chen, senior CSIRO research scientist and Lab22 team leader, said the project shows what becomes possible when students get access to industrial metal AM equipment. "This rapid concept-to-test approach will speed up development cycles in engineering, helping to innovate and bring down cost," added Prof. Richard Sandberg, who supervised the capstone.

The team already has plans to integrate Slinky into a full rocket. That would be the next logical step for ARES Rocketry, and it is exactly the kind of iterative development cycle that additive manufacturing enables.