The CleanLE2 project builds on the knowledge acquired in the first CleanLE project, where different basic principles for the in-flight decontamination of a wing leading edge have been evaluated. In the CleanLE2 project we take it a step further by developing the concept retained at the end of the first project. During the 24 months of the project the aim is to redesign the device, build it and test it in the laboratory on a real wing. In addition wind tunnel tests of the wing with the device attached will be performed to assess the impact on the aerodynamic efficiency and, more important, the forces acting on the device during its use.
Prototype working principle
The idea is to have 2 cleaning shuttles on both sides of the wing, rolling from wing root to wing tip and back. The cleaning is ensured by sponges on the shuttle path and by a string tensioned between the shuttles for the leading edge.
The reference wing is designed for laminar flow on both sides (pressure and suction side). As a consequence, no slits are allowed on the wing skin and hence it is not possible to have a direct mechanical link between the shuttle and the aircraft structure. A magnetic coupling is therefore proposed, with devices moving inside the wing that impose the translation movement of the shuttles and ensure the link.
Several tests will be performed during the project. Preliminary tests will support the design of the device by providing early feedback on the system's kinematics, on the cleaning efficiency and on the magnetic coupling effectiveness.
Extensive tests on the prototype will provide valuable information on the effectiveness of the concept and will allow for the optimization of the concept and ultimately for the increase of its TRL level from 3 to 5.
Wind tunnel tests
Wind tunnel tests will investigate the flow field around the cleaning shuttles. Additionally they will allow the validation of the computational fluid dynamics simulations performed in the design phase to assess the maximum forces encountered in flight. This is important for the sizing of the magnets.