In May 2021, aerospace components supplier GKN successfully supplied Rolls-Royce's OEM aircraft engine with an internal compressor housing -- ICC -- made entirely from 3D printing. The ICC will be used in a demonstration model of Rolls-Royce's Ultra Fan engine as part of Clean Sky 2, Europe's largest aeronautical research project, which aims to reduce CO2 emissions and noise levels from today's aircraft engines. The Clean Sky 2 project, supported by the EU Horizo 2020 program and funding from the aviation industry, aims to strengthen partnerships in the field while also promoting healthy competition. Henrik Runnemalm, vice president, Swedish Technology Centre, GKN Aerospace, said: "The ICC delivery of the Ultrafan engine to Rolls-Royce is a true milestone. It represents the success of the Clean Sky 2 collaboration and we are pleased to have applied the latest sustainability technologies to the ICC development. We are very proud to be a partner with the Rolls-Royce team and to contribute to the future of this energy efficient aero-engine."

 Ultra Fan Engine

The newest addition to the Rolls-Royce engine portfolio is the Ultra Fan engine. It is reported that the Ultra Fan is 25% more fuel efficient than the first-generation Trent engine and features a new engine core architecture. The system, which has a 140-inch diameter blade, has been described as a new way to achieve 'sustainable air travel'. With carbon-titanium fan blades and composite housing, the new engine can reduce the weight of the aircraft by up to 680 kilograms. It is also equipped with a new gear design that provides efficient power for high thrust and high bypass rate. Rolls-Royce plans to conduct a full ground test of the engine in 2022, with flight tests to follow shortly thereafter. Chris Cholerton, President of Rolls-Royce Civil Aviation, said: 'Our first engine concept, the UF001, is now fully equipped and I am really looking forward to seeing it in post-production and ready for testing. This is a more sustainable form of travel that the world is looking for, especially in the wake of the COVID-19 outbreak. It also makes me and our team very proud, because our work is part of the solution."

Manufacturing UltraFan ICC

As the core partner for the Clean Sky 2 project and manufacturing of the display model, GKN was responsible for the design and manufacture of ICC components. The key structure is designed to be positioned between the compressor housings to transfer the eddy current load down to the engine housings and the thrust mounting seat. While most ICC components are manufactured using traditional casting techniques, some of the attachment parts are 3D printed with metal. The production process also includes new welding methods based on computer simulations, aerodynamically optimized ventilation systems and acoustic characteristics, and a shorter main air duct design. GKN Aerospace's ICC component development process was also supported by the IND Demo project sponsored by Vinnova and the Vastra Gotaland region in Sweden. Additive manufacturing technologies for turbine engine components are also gaining traction in development projects such as the Ultra Fan engine. Earlier this year, Energy technology company Siemens Energy developed a new digital repair chain dedicated to new capabilities for 3D printing of gas turbine blades manufactured by traditional processes. In addition to the blade MRO, the chain is designed to provide improvements and upgrades, in particular by installing complex cooling channels at the tip of the blade to reduce the risk of cracks and defects in the component. Two other companies, GE Aviation and GE Additive, have also recently unveiled four new 3D-printed gas turbine engine parts for the first time. In fact, GE already has a set of casting molds for making air-driven adaptor caps, but when cost and lead time were critical factors, it was natural to shift its investment from casting to metal additive manufacturing.