Numerical, Experimental and Flight Investigation of MAV Aerodynamics

Moscow Institute of Physics and Technology(MIPT),. Department of Aeromechanics and Flight Engineering. 16, Gagarina str., Zhukovsky, Russia, 140180.
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Numerical, Experimental and Flight Investigation of MAV Aerodynamics Sergey V. Serokhvostov Moscow Institute of Physics and Technology(MIPT), Department of Aeromechanics and Flight Engineering 16, Gagarina str., Zhukovsky, Russia, 140180 ([email protected]) and

A.V. Kornushenko, A.V. Shustov and S.V. Lyapunov Central AeroHydrodynamical Institute (TsAGI) 1, Zhukovsky str., Zhukovsky, Russia, 140180

PURPOSES 1. Investigate the influence of MAV wing shape on aerodynamical characteristics 2. Investigate the influence of profile shape and winglets on aerodynamical MAV characteristics 3. Investigate the influence of powerplant on aerodynamical MAV characteristics 4. Investigate the influence whole MAV design on aerodynamical MAV characteristics 5. Investigate possibility of numerical investigation of pressure distribution 6. Compare the results of wing tunnel and flight experiments

WING TUNNEL AND EXPERIMENTAL MODELS

Wing 1

Wing 2

Wing 3

Wing 4

Wing 5

=1.5

=1.92

=1.7

=1.76

=1.82

Wing 1

Wing 7

Wing 8

Wing 9

flate plane

profile

profile, flexible

profile, winglets

WIND TUNNEL EXPERIMENTS Influence of wing shape investigation Wing 1

Wing 2

Wing 3

Wing 4

Wing 5

=1.5

=1.92

=1.7

=1.76

=1.82

Wings with the same wing span DRAG coefficient vs. LIFT coefficient

DRAG vs. LIFT

Drag for the same lift is independent of wing shape for moderate CL

WIND TUNNEL EXPERIMENTS Influence of wing shape investigation “Energetic” characteristics (POWER)-1 coefficient vs. LIFT coefficient

(POWER)-1 vs. LIFT

WIND TUNNEL EXPERIMENTS Influence of profile investigation Wing 1

flate plane

Wing 7

Wing 8

profile

profile, flexible

Wing 9

profile, winglets

Curved and flexible profile gives some advantage in comparison with rigid flat plane. Winglets are effective for CL>0.3

WIND TUNNEL EXPERIMENTS Influence of propeller investigation

Flow from powerplant allows to obtain higher values of CL. Polar curves are the same up to separation

WIND TUNNEL EXPERIMENTS Characteristics of the whole MAV

Empennage, additional parts and devices decrease maximum of L/D up to about 20%

NUMERICAL INVESTIGATIONS Pressure distribution

Red line – XFoil with fixed transition location, blue line – XFoil with free transition location, small circles – experiment results

XFoil can be used for the pressure distribution and separation localization

FLIGHT EXPERIMENTS

SEPARATION OCCURS ONLY ON THE WING TIPS DURING THE LEVEL FLIGHT!

CONCLUSIONS The results obtained allow to make some conclusions. 1. XFoil program can be used to determine the location of separation bubble. 2. All the wing with the same wing span give nearly the similar characteristics in the region of moderate CL. 3. Profiled wing, flexible wing can improve the MAV characteristics. Winglets are effective for CL>0.3. 4. Wind tunnel experiment results are in coincidence with real flight. 5. The separation without re-attachment on the MAV with working powerplant occurs only on the wing tips.

Acknoledgements This work was carried out under support of Russia’s President Grant for Young Scientists Support MK-5370.2006.8 and RFBR Grant (project 07-08-00820-a).