A major milestone within the Clean Sky 2 project ALVAR has been achieved by successfully completing wind tunnel testing in the DNW-LLF. The ALVAR project aims at demonstrating technology readiness for a novel suction skin structure, the tailored skin single duct (TSSD). The TSSD skin is used in hybrid laminar flow control to delay laminar to turbulent transition of the flow and reduce aerodynamic drag. Tests were conducted to check the effectiveness of the TSSD concept in its ability to stabilise a laminar boundary layer at high Reynolds numbers. The 1:1 scale vertical tail plane model with novel TSSD suction nose in the leading edge was provided by the DLR and represents a relevant aircraft structure to test the TSSD technology. Laminar flow was confirmed by infrared thermography and the TSSD panel performed as predicted. These results will pave the way for introducing the technology on future large commercial aircraft which could potentially reduce fuel consumption by 12-15%. The two-week wind-tunnel test campaign at the DNW-LLF is the high point of the work performed over the last year by DNW staff together with scientists from the Institute of Fluid Mechanics at TU-Braunschweig and the German Aerospace Center, DLR. The ALVAR project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 882646.
