Dragonflies and CoFlow Technology

Dean Sigler Biomimicry, Electric Powerplants, Sustainable Aviation Leave a Comment

A Different Approach to Regional Aerial Mobility Dr. Gecheng Zha sees a relationship between dragonflies and his CoFlow technology.  Mimicking the look, and more importantly, the aerodynamics of the creature.  Director of the Aerodynamic and CFD Lab, University of Miami (UM), Zha is expanding his research into eVTOL (electric Vertical Take Off and Landing) aircraft, Martian exploration, and large scale sailing ships. His talk at the 2019 Sustainable Aviation Symposium at UC Berkeley was a revelation and his subsequent work shows the multiple directions in which his CoFlow technology can be applied. Urban and Regional Air Mobility CoFlow Jet does the improbable trick of pushing air over the wing, only to have it sucked in near the trailing edge, passed through an internal compressor and blown out through slots in the wing’s leading edge, creating a steady stream that increases the lift coefficient and lowers the drag coefficient.  Zha claims that this enables the use of battery power because the propulsors can …

EAS VIII – A Day and a Half You’ll Never Forget

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Who would pass up a chance to stay at a nice resort, attend lectures that challenge and inspire, and meet at poolside with speakers who bring some of the sharpest minds in the world to bear on some of the biggest problems we all face?  Let’s face it.  Global warming probably won’t be going away anytime soon, and aviation seems destined to play a bigger part in polluting our otherwise near-perfect atmosphere. Unless…we learn how to make our favorite activity (in the top five for most of us, anyway), into a more responsible way to travel and recreate.  Since solving the problems which go with that responsibility will involve the best in aerodynamics, power systems and new, efficient technology, the CAFE Foundation has invited experts in these fields with demonstrated successes in meeting such challenges. To be held April 25 and 26, 2014 at the Flamingo Resort in Santa Rosa, California, the event will host speakers on everything from practical, …

Ultra High Lift Without Flaps

Dean Sigler Diesel Powerplants, Electric Powerplants, GFC, Sustainable Aviation 1 Comment

Dr. Gecheng Zha, an Associate Professor with the University of Miami has an impressive set of credentials, culminating in a Ph.D.from the University of Montreal, Ecole Polytechnique.   That, and his impressive body of work helped impress the audience at the seventh annual Electric Aircraft Symposium this last April. His work over the last decade has focused on generating high lift and low drag through circulation control on wings – even leading to the concept that wings can generate thrust instead of drag.  This integration of aerodynamic forces would lead to highly efficient aircraft capable of flying on little – or even no power. Earlier attempts to increase lift and decrease drag have relied on sometimes complex, multiply flapped and slotted wings which require powerful mechanical actuators to work their magic. Others have used rotating cylinders laid spanwise on wing leading and trailing edges, or active suction or blowing to achieve their goals.  Zha has looked at these and other …