The race to a complete, 3D printed rocket engine is on – NASA has been working for years to develop a fully 3D printed rocket engine, and this summer Rocket Crafters, Inc. received a DARPA contract to build and test a 3D printed, large-scale rocket engine. Now, in just four months, a team of Australian engineers from Monash University and its spin-out company Amaero Engineering has successfully designed, built, and test-fired a 3D printed rocket engine. The joint effort between the two, also supported by Woodside Energy through the Woodside Innovation Centre at Monash, has been dubbed ProjectX, a unique multi-chamber aerospike rocket engine design that flips the traditional shape of engines. This achievement is a direct illustration for Australian industry of the potential of 3D printing technology.
The engineers from Monash have created NextAero, a new venture that will move its concepts onto a global stage in the aerospace industry; according to the NextAero team, an aerospike nozzle is one of the world’s most complicated rocket engines. It works by firing gases along a spike, and atmospheric pressure creates a virtual bell shape, traditionally called a de Laval nozzle; an aerospike is basically an inverse de Laval. The spike’s shape lets the engine continue to maintain high efficiency at high altitudes.
Together with their partners two years ago, Monash researchers were the first ever to 3D print metal jet engines, based on existing engine designs. Due to this successful project, Amaero began winning contracts all over the world with some of the major aerospace companies. According to Monash, Amaero challenged its researchers to design the rocket engine that would make full use of 3D printing technology’s “near limitless geometric complexity.” Soon after, Amaero 3D printed the design, which was recently test-fired.
Marten Jurg, an engineer with Amaero, explained, “Traditional bell-shaped rockets, as seen on the Space Shuttle, work at peak efficiency at ground level. As they climb the flame spreads out reducing thrust. The aerospike design maintains its efficiency but is very hard to build using traditional technology. Using additive manufacturing (printing) we can create complex designs, print them, test them, tweak them, and reprint them in days instead of months.”
The engine, a complex, multi-chamber design, was 3D printed with SLM technology on an EOS M 280 using Hasteloy X, a high strength superalloy based in nickel. Oxygen and natural gas, which consists mostly of methane, are the engine propellants. Aerospikes are very hard to build, because the spike structure has to be supported inside the rocket exhaust, and engineers have to build a complex network of subsurface cooling channels that carry the heat away and keep the nozzle from melting. But thanks to 3D printing technology, the ProjectX engine, which has a design thrust of 4kN (about 1,000 lbs) and a 3D curved combustion chamber and nozzle, is much shorter than the typical de Laval nozzle.
“We were able to focus on the features that boost the engine’s performance, including the nozzle geometry and the embedded cooling network,” said project lead Graham Bell. “These are normally balanced against the need to consider how on earth someone is going to manufacture such a complex piece of equipment. Not so with additive manufacturing.”
According to NextAero, “This means that a more powerful engine can be made in a smaller space within the confines of the additive manufacturing machines.”
The NextAero venture will begin its journey to the global aerospace industry later this month at the International Astronautical Congress in Adelaide. Going from only a concept to a fully realized project and testing in only four months is quite an accomplishment.
Professor Nick Birbilis, head of the Material Science and Engineering Department at Monash, said, “It illustrates what’s possible for research and industry. Through our spin-out company, Amaero, Australian companies can design, print, and test metal components for everything from aerospace to surgical instruments, hose fittings to air conditioning parts.”
Check out the video below to see the 3D printed rocket engine in action:
Discuss this article and other 3D printing topics at 3DPrintBoard.com; you can also leave a Facebook comment below.[Source: Business Insider Australia]