Fraunhofer Institute of Manufacturing Technology and Advanced Materials IFAM will participate in the ILA Berlin Air Show which will take place during the period May 20-25, 2014 in Berlin, Germany. ILA Berlin Air Show represents the market place and meeting platform for the global aerospace industry, all suppliers and service providers as well as all international clients. Some of the Highlights of this event involve:
- 282 aircraft of all sizes and categories on display on the ground and in the air
- impressive flying displays
- hot topics (e.g. eco-efficient air traffic, life-cycle management, up-to-date R&D trends)
- platform for suppliers of single-aisle and wide-body aircraft; engines and peripheral systems
During this event the work undertaken by the Fraunhofer Institute of Manufacturing Technology and Advanced Materials IFAM in regards to the morphing wing within the SARISTU project will be presented. In particular, within the SARISTU project Fraunhofer IFAM aims at maximizing wing aerodynamic performance of the adaptive trailing edge so as to lead to considerable reduction in fuel consumption. In particular, Fraunhofer IFAM is heavily involved in: i) the finalization of the Adaptive Trailing Edge Device (ATED), and ii) the development of a winglet with active trailing edge (WATE).
Within the aforementioned activities, work is performed in order to develop an adaptive trailing edge according to the Certification Specifications for large airplanes (CS-25) posed by the European Aviation Safety Agency (EASA). This work resulted in a 5-hinge concept for the ATED and a single hinge concept for the WATE. Both concepts involve the computation of safety factors for ultimate loads for relevant load cases, e.g. continuation of the flight with hinge failure.
Within the finalization of the Adaptive Trailing Edge Device, Fraunhofer IFAM is responsible for the design of the morphing skin, which ensures continuous airflow at the ATED, thereby reducing drag and fuel consumption. Within the development of a WATE, Fraunhofer IFAM is responsible for the development of the morphing part between the tab and the non-morphed part of the WATE. Here, continuity of the airflow is obtained by closing the aerodynamic gap between tab and wingtip.
In both these activities, Fraunhofer IFAM is responsible for the material selection, the determination of material data, and the calculation of material models for all elastomeric morphing parts. One of the most important requirements to the material is a constant, high flexibility throughout the whole temperature range of the aircraft wing surface (-55 °C to 80 °C). Last but not least, all elastomeric components for these activities (morphing skin and morphing part at winglet) are produced at Fraunhofer IFAM.
All previous concepts for seamless morphing lacked of appropriate elastomeric materials. In the proposed design, stability against air pressure and high flexibility are obtained by a multi-material mix. Morphing parts are manufactured in a co-bonding/co-curing process of metallic and elastomeric materials, including casting and temperature control. Only this specific process leads to a seamless skin with required material properties and high adhesion strength between all material interfaces.
The results obtained in the current status of SARISTU show that a conformal shape change in a wingtip with an active trailing edge can be achieved by using modified elastomers. Major achievements are the proof of sufficient stiffness and strain at fracture over the temperature range and the proof of fatigue resistance.