On the first day of the Space Tech Expo, Bremen, Pangea Aerospace, the innovative space propulsion company based in Barcelona (Spain), announced the successful hot fire testing of their DemoP1 aerospike engine.
The test campaign represents a huge milestone in the company’s journey to bring their first aerospike engine in flight.
Undergoing the needs for a testing facility, the DLR’s Lampoldshausen site was chosen, where a DLR team investigated the world’s first additively manufactured MethaLox aerospike engine. The prototype was hot-fired several times, being tested for almost 3 minutes (160 seconds) in one single firing, verifying the feasibility of dual regenerative cooling on aerospike engines for the first time in Europe.
While DemoP1 has a maximum thrust of 20kN, further steps are clear in the near future of the company, with an engine performing more than a hundred kN of thrust already thought of.
Furthermore, Pangea Aerospace recently won a contract from CNES (French Space Agency) to start a study on how its proprietary technology could be applied to larger engines – in the order of 1 MN -, such as the ones powering Ariane and other heavy launcher engines. The company has also received interest from other commercial organizations and space agencies. Anyway, a larger engine will be an affordable task for the team, as cooling is the most critical challenge in Aerospike engines development, causing more problems in smaller engines compared to the larger ones.
Being aerospike engines a disruptive technology, Pangea Aerospace team decided to make an all-in, bringing as much innovation as they could in the engine design. From nozzle shape to manufacturing technique, including fuels choice and engine materials, everything is innovative and outstanding in the project, while many challenges have already been overcome to get nearer to the first flight.
Increase complexity to enhance efficiency
The aerospike engine has been the saint grail for rocket scientists since it was first theorized in the 50’s. While different prototypes were developed and tested in the years, no one has ever flown.
Aerospike engines use a V-shaped nozzle to direct the exhaust gases that propel the rocket. As the nozzle is “open”, exhaust gases are always optimally expanded (the changing ambient pressure acts as a virtual nozzle). This means an aerospike nozzle can have maximum efficiency and thrust at ground pressure as well as in the higher atmosphere: a unique capability that allows for a huge 15% increase in efficiency with respect to currently used bell nozzles. In other words, you need 15% less fuel to bring the same mass to orbit. As these advantages arises where the bell nozzle needs compromises, that is in the atmosphere, aerospike nozzle is very suitable for small satellites being sent to LEO, and in the same way for first stages of larger launchers sending payloads to higher orbits or on interplanetary journeys. The company CEO and cofounder Adrià Argemí told us:
“We see a lot of micro launcher development in the future. We do believe that this type of engine technology unlocks the next generation of technology for the launchers, because aerospikes can really increase your payload capacity”.
Whether traditional aerospikes resemble a rectangular shape with two lines of injectors on the two sides, Pangea Aerospike team developed a circular cross section for its nozzle. Furthermore, the thrust vector control (TVC) has been provided with a traditional gimbal, as specific injectors control is too complex to achieve and unworthy in such a small engine. However, this choice could be available in larger engine.
Additive manufacturing: an enabling technology
Always working with the most advanced technologies, Pangea Aerospace has been able to solve the huge thermal problem of this kind of engine – whose central core is really demanding on cooling capabilities as surrounded by hot gases – thanks to additive manufacturing and new materials, such as GR Cop42, a copper alloy developed by NASA in 2019 for additively manufactured rocket engine combustion chambers.
Relying on additive manufacturing, the company has designed a new regenerative cooling system using both propellants for the highest possible cooling mass flow rate, with liquid oxigen cooling the plug and methane used in the external ring. Liquid oxygen and liquid methane – both in cryogenic state – go through complex shaped cooling channels before being ignited in the combustion chamber, thus allowing to cool down the engine and avoid its melting. Xavier Llairó, CCO and cofounder at Pange Aerospace, highlighted the successful design the company achieved:
“We are the only ones who are taking into account the cooling problem of the aerospike and we are actually solving this problem. And this 2 tons engine could actually fly. Right now we can say that we’re the most advanced company in terms of aerospike technology and our idea is to scale up this type of engine”.
To help in solving the thermal challenge, Pangea Aerospace has worked with Aenium, a 3D printing company based in Valladolid, as they share the exclusive capabilities in Europe for GRCop42. The used technique was Metal 3D Printing, also known as Selective Laser Melting (SLM). As Miguel Ampudia, CEO of Aenium, stated:
“Thanks to GRCop42 and Aenium’s technology, we have been able to manufacture this engine, which have one of the most complex designs. We are really proud to be able to manufacture this together with Pangea Aerospace, as it will help powering tomorrow’s space endeavors”.
What’s more, thanks to the simple two-pieces design allowed by 3D printing, the engine is extremely low cost to produce. Adrià Argemí said:
“We have unlocked aerospike technology at a very low cost. We have been able to hot fire successfully several times the same engine, demonstrating that the technology works and that we are ready for further challenges”.
A look into the future: reusable engines for reusable rockets
The choice of MethaLox engine, a world’s first for aerospikes, is well driven by the needs of commercial space era. While still providing a better specific impulse than KeroLox, the MethaLox compound has a higher density than HydroLox, thus producing the needed thrust to fight gravitational losses during atmospheric launch phase. Aside these good properties, Pangea Aerospace team chose the methane and liquid oxigen compound as methane is cheaper and much easier to handle, transport and store, and it burns very cleanly and efficiently contributing to ensure the engine reusability design target of more than ten firings.
“The reason why we chose this propellant is of course reusability. We want not only to have a reusable engine but also a reusable launcher in the future. You can easily reuse our engine several times. This prototype (the DemoP1) has already been fired 9 times.”
added Adrià Argemí, explaining how reusability allows the next step in Pangea’s journey: a fully fast-reusable rocket, with almost no refurbishment. In fact, the company has been funded by the European Commission to lead the RRTB project – Recovery and Return-to-Base – to investigate this topic. The program will focus on the recovery of the MESO microlauncher to validate key technologies for cost-effective and safe reuse of small launchers.
Pangea Aerospace has raised more than 3 million euros from different venture capital firms, such as Inveready, Primo Space, E2MC, Dozen investments and CDTI Innvierte. The company has also received grants and public funding for around 3,5 million euro to research on its technologies and today employs around 20 people.
About Pangea Aerospace
Pangea Aerospace is a company based in Barcelona and founded in 2018 with the objective of lowering the cost of launch through the development of disruptive launch technology in the fields of propulsion and recovery. Thanks to additive manufacturing they have been able to solve the historic challenges of aerospike engines and to do so at a very low cost. Furthermore, they have the ambition to reuse its engines and they use liquid oxygen and liquid methane, one of the most environmentally friendly and efficient propellant combination.
The company has raised more than 3 million euros from different venture capital firms, such as Inveready, Primo Space, E2MC, Dozen investments and CDTI Innvierte. The company has also received grants and public funding for around 3,5 million euro to research on its technologies and today employs around 20 people. Adrià Argemí is the CEO of the company and administrates it together with the other cofounders: Xavier Llairó (CCO), Federico Rossi (Head of propulsion), Nicola Palumbo (Head of mechanics), Luis Bellafont (CFO) and Rasmus Bergström (Head of flying vehicles).
More about GRCop42
GRCop-42 (Cu – 4 at.% Cr – 2 at.% Nb) is a high conductivity, high-strength dispersion strengthened copper-alloy for use in high heat flux applications such as liquid rocket engine combustion devices. This alloy is part of the family of NASA developed GRCop, copper-chrome-niobium alloys. GRCop alloys were developed for harsh environments specific to regeneratively-cooled combustion chambers and nozzles with good oxidation resistance. Significant development was completed on the GRCop-84 and GRCop-42 alloys in the extruded wrought form demonstrating feasibility for combustion chambers. NASA has developed a process for additive manufacturing, specifically Powder Bed Fusion (PBF) or Selective Laser Melting (SLM), of GRCop-42 establishing parameters, characterizing the material, and completing testing of components with complex internal features.
A few advantages have been shown with the GRCop-42 that include higher conductivity and faster build speeds over the GRCop-84, and a simplified powder supply chain. Initial property development has shown that it is possible to produce high density builds with strengths equivalent to wrought GRCop-42 and a conductivity greater than GRCop-84. (Source: Paul R. Gradl et al., GRCop-42 Development and Hot-fire Testing Using Additive Manufacturing Powder Bed Fusion for Channel Cooled Combustion Chamber. 55th AIAA/SAE/ASEE Joint Propulsion Conference 2019)
Courtesy of Pangea Aerospace
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