Design methodology for trailing-edge high-lift mechanisms

A new methodology has been developed that integrates the preliminary wing design with trailing edge high-lift systems and accounts for three-dimensional flap kinematics. The high-lift system in the developed application includes the kinematic synthesis of four common mechanisms (dropped-hinge, four-bar, link-track and hooked-track) and a preliminary actuation architecture. The paper details how each of these mechanisms is synthesized based on a set of intuitive input requirements such as gap and overlap dimensions in landing and take-off configuration. A SimMechanics multi-body mechanism model is generated to obtain the internal loads of the mechanism and actuation torque. The mechanisms and actuating drive train are structurally sized, leading to a determination of system weight and power consumption. A weight measurement of the outboard hooked-track mechanism of a VFW-614 flap has been compared to a modeled hooked-track mechanism by using the proposed method. This resulted in a 13 % underestimation of the mechanism weight, which was attributed to modeling simplifications, sizing assumptions and a crude aerodynamic load estimation. A comparison study between the four different mechanism types to be applied on a Boeing 777 wing, shows that the method can give the designer valuable insight in the gap/overlap behavior of the flap during deployment as well as an initial estimation of the difference in required fairing size, mechanism weight, and actuation power between the four mechanisms.Flight Performance and PropulsionAerodynamics, Wind Energy & Propulsio