Entwurf eines Hochauftriebssystems für ein schallimmissionsarmes Mittelstreckenflugzeug

Abstract

The DLR project "Low noise medium-range aircraft" (SIAM) has set itself the goal of designing an aircraft with the boundary conditions of "Flightpath 2050" in order to develop a significantly quieter configuration than modern conventional aircrafts with the most effective noise reduction technologies. Based on the work of Iwanizki et al., the present paper describes the detailed design of a low-noise blended wing body with attached T-tail (hybrid wing body, HWB), which has considered the use of noise reduction technologies right from the start. As a basis for the wing design, the preliminary design and engine integration including the center body design are summarized. The final engine installation is a noise shielding effectively podded engine design at a streamwise position at 63 % of the center body length with an achieved drag reduction of dCD = -0.0107 compared to the center body with unadapted integration. Based on the preliminary and the center body design, the wing geometry was built up with four section profiles. The profiles were designed using the inverse design capabilities of the DLR FLOWer code realizing a local lift coefficient of cl = 0.42 at Ma = 0.78 and a very limited supersonic region. Based on the cruise wing design, the high-lift configuration of the HWB with a gapless plain flap and an aileron was then realized, first with the help of 2D-RANS and afterwards 3D-RANS studies. Furthermore, a trailing edge flap with form adaptive shape was designed in order to realize a high-lift system without side edges reducing the noise emission of the wing further. The CFD investigations of the 3D high-lift configuration showed that the targeted lift coefficients of CL,TO = 0.76 and CL,LDG = 0.96 can be achieved by the HWB with the use of the designed conventional plain flap as well as with the morphing flap. The successful design of a gapless flap as high-lift system as well as the integration of the shielded engine are important steps of realizing a low-noise HWB regarding the goals of "Flightpath 2050".