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    Education in Research through Research


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    Education in Research through Research


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    Education in Research through Research


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  • von Karman Institute for Fluid Dynamics

    Education in Research through Research


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  • von Karman Institute for Fluid Dynamics

    Education in Research through Research


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Co-Flow Jet Active Flow Control Airfoil to Achieve Ultra-High Lift and Efficiency

Monday 18 July 2016 - Monday 18 July 2016

Registration (only for external people) to the VKI secretariat: This email address is being protected from spambots. You need JavaScript enabled to view it., Phone: +32 2 359 96 04

Dr. Gecheng Zha, Professor
Dept. of Mechanical and Aerospace Engineering
University of Miami, Coral Gables, FL 33146, USA
This email address is being protected from spambots. You need JavaScript enabled to view it.
www.miami.edu/acfdlab

Abstract:

This seminar introduces the novel concept of co-flow jet (CFJ) active flow control airfoil, which withdraws a small amount of mass flow near the trailing edge, pressurizes the flow, and then ejects the flow as a jet near the leading edge behind the airfoil suction peak(lower left figure). It is a zero-net mass-flux flow control airfoil with a very low energy expenditure mechanism of suction and injection. It creates a super-suction effect at leading edge similar to bird flapping wings. The CFJ airfoil is demonstrated both in wind tunnel experiments and CFD simulation to dramatically enhance lift, generate thrust (negative drag), and increase stall margin. The maximum lift coefficient obtained recently by CFD simulation reaches 10.6 at Cμ=0.35 and angle of attack of 70deg with the flow still attached(lower right figure). The circulation is so large that the stagnation point is detached from the airfoil body. It largely exceeds the theoretical limit of potential flow, CLmax=2π(1+t/c)=7.6 . We hence name it super-lift coefficient. The CFD simulation also indicates that it is very effective to enhance the transonic supercritical airfoil lift and aerodynamic efficiency at cruise condition when the flow is benign at low angle of attack. All these features enable the CFJ airfoil to be used in the whole flight envelop without conventional high lift flap systems. This seminar will include some wind tunnel experimental results at low speed, control volume analysis to consider the jet reactionary force, CFD simulations, a conceptual design of an electric CFJ GA aircraft that more than doubles the range of a same size conventional design, and future work and direction.

 co-flow jet

Bio-Sketch:

Dr. Ge-Cheng Zha, professor, is the director of the Aerodynamics and CFD Lab at the University of Miami. Dr. Zha is the originator of the CFJ airfoil and is granted two patents for that invention. Dr. Zha’s research interests include CFD high order algorithm/code development, turbomachinery aeromechanics, airfoil active flow control, new concept aircraft design, turbulence simulation, aeroelasticity fluid-structural interaction, and design optimization. Before joining UM, Dr. Zha had extensive experience working in aerospace industry (GE Aircraft Engines, Pratt & Whitney) and government labs(AFRL). Dr. Zha’s research at UM has been funded by NASA, ARO, AFOSR, NRC, AFRL, GUIde, CIRA, Siemens, etc. Dr. Zha received his Ph.D. degree from the University of Montreal in 1994. In Spring of 2000, he studied at MIT as a special student in the Dept. of Aeronautics and Astronautics. He is the NASA NIAC Fellow, AIAA Associate Fellow, and ASME Fellow. He is also the executive committee member of Center for Computational Sciences at UM. From June 2007 to June 2009, Dr. Zha was the director for Miami Wind TM research center. Dr. Zha has 43 journal publications and over 120 conference publications.

 

Location : von Karman Institute for Fluid Dynamics, Waterloosesteenweg 72, B-1640 Sint-genesius-Rode, Main Conference Room