Comparison of smart wing concepts for transonic cruise drag reduction

Abstract

A method is being developed to employ TERFENOL to optimize the shapes of wings for minimum drag during transonic cruise. Potential advantages include enhanced UAV attack and surveillance capabilities through increased dash speed, longer loiter, and extended range as well as decreased fuel expenditures for transport aircraft. Two smart-wing concepts were compared: an adaptive wing with the capability to change the shape of the wing box and a smart trailing edge that modifies camber while maintaining a smooth upper surface. While the adaptive wing provides the most capability to change the structural shape to minimize shock- induced drag, when actuator- and structural-weight penalties were considered as well as reliability and maintenance, it was determined that the smart trailing edge is the better concept. Numerical optimization of a simplified smart trailing edge determined the optimum configuration and optimum deflections for minimum drag. The system has the potential to extend the range of a small-fuselage large-wing UAV bomber by 9% and increase its loiter time by 11%. Magnetic and electronic design improvements to the TERFENOL linear-wave motor have been identified that will enable us to miniaturized it for UAV applications while doubling its actuation force and speed, and halving its power.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.