Analysis of Steady-State Aerodynamic Performance and Control Surface Effectiveness of a High-Speed Projectile

This study describes the depth and straight motion control performance depending on control surface combinations of a supercavitating underwater vehicle. When an underwater vehicle experiences supercavitation, friction resistance can be minimized, thus achieving the effect of super-high-speed driving. Six degrees of freedom modeling of the underwater vehicle are performed and the guidance and control loops are designed with not only a cavitator and an elevator, but also a rudder and a differential elevator to improve the stability of the roll and yaw axis. The control performance based on the combination of control surfaces is analyzed by the root-mean-square error for keeping depth and straight motion.

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Pneumatic lift and control surface technology applied to High Speed Civil Transport configurations

10.2514/6.1997-36 ◽

1997 ◽

Cited By ~ 2

Author(s):

Robert Englar ◽

Curt Niebur ◽

Scott Gregory ◽

Robert Englar ◽

Curt Niebur ◽

...

Keyword(s):

High Speed ◽

Control Surface ◽

And Control

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Effects of Phase Relation between Forewing and Hindwing on Aerodynamic Performance in Dragonfly Flight

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.709.245 ◽

2014 ◽

Vol 709 ◽

pp. 245-251

Author(s):

Jin Zhao Yan ◽

Meng Zong Zheng ◽

Zhi Ping Li ◽

Qiu Shi Li

Keyword(s):

Phase Relation ◽

High Frequency ◽

Small Amplitude ◽

High Speed ◽

Micro Air Vehicles ◽

Aerodynamic Performance ◽

Stability And Control ◽

High Acceleration ◽

The Stability ◽

And Control

Dragonflies possess one of the most maneuverable flights among various insects. As the bionic Micro Air vehicles (MAVs) with the flight capabilities like dragonflies have been widely applied, detailed studies of dragonfly flight become critical and necessary for improvement and accomplishment of MAVs design. The phase relation between the forewings and hindwings is the most distinct feature of dragonfly flight and it plays an important role in the aerodynamic performance. In this paper, both tethered and quasi-free flapping flight of the dragonfly Pantala flavescens was filmed using a high-speed camera in indoor laboratory. Dragonflies tend to flap in-phase when an additional force is expected, while out-of-phase flapping is conducive to the stability and control of flight. In the takeoff maneuver, the large-and small-amplitude wingbeat alternated. Dragonflies obtain a high acceleration rapidly by the suddenly enlarged wingbeat amplitude which increases by 42%, and maintain the velocity and make ready for following acceleration by the small-amplitude but high-frequency wingbeat with amplitude decreases by 51% and frequency increases by 30% relatively.

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Improvement of Aircraft Aerodynamic Performance Using Piezoelectric Actuators

MRS Proceedings ◽

10.1557/proc-0888-v01-07 ◽

2005 ◽

Vol 888 ◽

Author(s):

Li Min ◽

Chen Wei-min ◽

Li Wei

Keyword(s):

Wind Tunnel ◽

High Speed ◽

Dynamic Pressure ◽

Bending Moment ◽

Piezoelectric Actuators ◽

Aerodynamic Performance ◽

Control Surface ◽

Flight Vehicle ◽

Rolling Moment ◽

Induced Drag

AbstractTo flight vehicle designer, the ability to adapt air vehicle aerodynamic shape so as to increase the optimum flight envelope is highly desirable. In this work, by distributing piezoelectric actuators on the top and bottom surfaces of a rectangular wing, the improvement of aerodynamic performance of flight vehicle is studied. The approach of the Fictitious Control Surface (FCS) is evaluated at a group of dynamic pressure and wing stiffness, through examining four aspects including the improvement of rolling power, the increase of lift, the decrease of the induced drag and the decrease of the bending moment at root of wing. Then an experimental model of high-speed wind tunnel is designed in order to validate the results of theoretical analysis. The ground tests and wind tunnel tests demonstrate that the lift and rolling moment can be increased by using the favorable aeroelastic effect. And quantificationally the experimental results agree well with the analytical results.

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