Reconfigurable Vertical Lift
Rosalind and John J. Redfern Jr. Chair and Aerospace Program Director
Mechanical Aerospace and Nuclear Engineering
Rensselaer Polytechnic Institute
Friday, October 11th, 2019
12:45 p.m. – 2:00 p.m.
As VTOL/hover-capable aircraft are expected to do more – fly faster, heavier, higher, and in hotter conditions, there has been a tremendous interest over the last decade-and-a-half in the application of rotor morphing (or shape adaptation) as an attractive, and perhaps an enabling, technology option. Compared to fixed-wing aircraft morphing, rotor blade reconfiguration presents a stiffer challenge due to stringent space constraints, requirement to transfer power to the rotating system, and operation under very large centrifugal loads. The presentation covers various type of rotor morphing including span extension morphing, chord extension morphing, twist morphing or spanwise camber variation, as well as airfoil shape change for high-speed (reverse flow) conditions. The conditions in which various types of geometry changes are beneficial, along with the corresponding improvements in performance, operating envelope, and operational flexibility, are discussed in detail. The presentation also covers various implementation methods that have been developed and demonstrated, including autonomous shape change (without the use of dedicated actuators or power) realized through change in rotor RPM or ambient temperature. The lecture concludes with new ideas and work in the areas of coupling geometric and control reconfiguration, modular reconfigurable vertical lift (where a VTOL aircraft is assembled to optimally match the mission), and a discussion on future directions and opportunities.
Farhan Gandhi is the Rosalind and John J. Redfern Jr. ’33 Endowed Chair in Aerospace Engineering at Rensselaer Polytechnic Institute (RPI). He is also RPI’s Aerospace Program Director, and Director of RPI’s Center for Mobility with Vertical Lift (MOVE). His research interest and activities cover the areas of rotorcraft aeromechanics, advanced rotary-wing configurations, multi-rotor aircraft, as well as smart/adaptive structures. Dr. Gandhi has been a visionary on reconfiguration in vertical lift platforms and high-speed rotorcraft and is credited with some of the most significant pioneering work in these areas with support from US federal and state agencies as well as industry. He is a Technical Fellow of the Vertical Flight Society (formerly the AHS), winner of the 1998 AHS Francios Xavier Bagnoud Award and the 2007 Popular Mechanics Breakthrough Award (for morphing rotors). He is a past Chair of the AHS Dynamics and Aircraft Design Technical Committees, and the AHS Education Committee. Dr. Gandhi is author of 275 articles appearing in archival journals and technical conference proceedings. He has been an invited plenary/keynote speaker or panelist at numerous technical conferences and served as consultant to several VTOL companies including Boeing, Bell and Leonardo Helicopters.