TASK 1.2b
MINIATURE TRAILING EDGE EFFECTORS
FOR ROTORCRAFT APPLICATIONS
PRINCIPAL INVESTIGATORS
MARK MAUGHMER
GEORGE LESIEUTRE
GARY KOOPMANN
EARL DUQUE
GRADUATE RESEARCH ASSISTANTS
MICHAEL KINZEL
MICHAEL THIEL
BACKGROUND:
“REAL” GURNEY FLAPS
Wing trailing-edge
Gurney flap
BACKGROUND
• MINIATURE TRAILING-EDGE EFFECTORS (MiTEs)
- MOVABLE TABS, PARTIAL SPAN
- CONSIDERED BY VanDam, Eaton, others
• MiTEs HAVE POTENTIAL TO IMPROVE
- ROTOR PERFORMANCE
• INCREASE MAX LIFT TO REDUCE RETREATING-BLADE STALL
• REDUCE COMPRESSIBILITY EFFECTS ON ADVANCING SIDE
- VIBRATION CONTROL
Wing trailing-edge
Variable
Height
• SPANWISE & AZIMUTHAL
LIFT DISTRIBUTIONS
Dist. from TE
Active MiTE
TECHNICAL BARRIERS
• ACTUATION (4/REV => 20 Hz FREQ.)
• DYNAMIC PERFORMANCE NOT UNDERSTOOD
• ROTOR PERFORMANCE EFFECTS
OBJECTIVES
EXPLORE UTILITY OF ACTIVE GURNEY FLAPS
APPROACHES:
• AERODYNAMIC UNDERSTANDING:
• EXPERIMENTAL: 2D STATIC / DYNAMIC
• NUMERICAL: 2D STATIC / DYNAMIC
• POTENTIAL FOR ROTORCRAFT:
• FLIGHT PERFORMANCE – IMPROVED PREDICTION METHODS
• IMPLEMENTATION:
• ACTUATION
EXPECTED RESEARCH RESULTS:
• AERODYNAMIC EFFECTS OF SIZE AND LOCATION
• BETTER UNDERSTANDING OF GURNEY FLAP PHYSICS
• DETERMINE EFFECTS ON ROTOR PERFORMANCE
• DEVELOP VIABLE ACTUATION METHODS
• OBTAIN DYNAMIC WIND-TUNNEL DATA
EXPERIMENT: TRANSITION FIXED AT 5%c
EXPERIMENT: GURNEY LOCATION AND SIZE
GF HEIGHT
0.005c
0.01c
0.02c
NUMERICAL INVESTIGATION: CFD STREAKLINES
NUMERICAL INVESTIGATION: CFD STREAKLINES
AERODYNAMIC MODELING OF MiTES:
• MACH NUMBER AERO.
EFFECTS FOR A
GURNEY FLAP
• CONSISTENT WHEN
CONSIDERING ’
'
    Stall
  Stall    Stall
cl ,GF (M , ) = cl ,GF ( ')
AERODYNAMIC MODELING OF MiTES:
INDICIAL RESPONSE AND HARIHARAN-LEISHMAN
UNSTEADY FLAPPED AIRFOIL MODEL
• AVERAGED
INDICIAL RESPONSE
IS SIMILAR TO PLAIN
FLAP
• ALLOW THE
INVESTIGATION OF
UNSTEADY PLAINFLAPPED AIRFOIL
THEORIES
AERODYNAMIC MODELING OF MiTES:
UNSTEADY FLAPPED AIRFOIL MODEL APPLIED TO MiTES
k=0.14, M=0.1, =0deg
k=0.5, M=0.6, =0deg
AERODYNAMIC MODELING OF MiTES:
UNSTEADY FLAPPED AIRFOIL - DYNAMIC STALL MODEL
DYNAMIC STALL MODEL
UNSTEADY FLAPPED AIRFOIL MODEL
CFD – OVERFLOW2
EFFECT OF MiTE POSITION:
• VORTEX STREET FORMS CREATES
HIGH FREQ. OSCILLATIONS
• TRAILING EDGE PLACEMENT
AGREES WELL WITH THEODORSEN
CIRCULATORY THEORY
(a) xMiTE=1.0c
• UPSTREAM PLACEMENT HAS
LARGE DYNAMIC LOADS AND
INCREASED LAGS
(b) xMiTE=0.9c
(a)
(b)
PERFORMANCE ANALYSIS: OPTIMAL DEPLOYMENT STRATEGY
REASONABLE FOR STEADY ASSUMPTIONS, BUT NOT WHEN
UNSTEADY AERO. AND DYN. STALL ARE CONSIDERED
PERFORMANCE ANALYSIS: FORWARD FLIGHT
PERFORMANCE ANALYSIS: MiTE DEPLOYMENT
PERFORMANCE ANALYSIS: FORWARD FLIGHT
WITH VARIATIONS IN AIRFOIL TRANSITION RADIUS
PERFORMANCE ANALYSIS: EFFECT OF MiTE DRAG TO
PERFORMANCE ENHANCEMENT
NOTE: DEPLOYMENT IS SCHEDULED TO
MINIMIZE PITCHING MOMENT
ACTUATOR DESIGN
• DESIGN FOR AERODYNAMIC BENEFITS
– OPERATING FREQUENCIES OF 4 – 5 Hz
• APPLY TO A VR-12 AIRFOIL
– HEIGHT: 0.01c
– LOCATION: 0.9c
Fig. from Johnson, W., Helicopter Theory
AERODYNAMIC
FORCE ON THE FLAP
•
•
•
•
•
Re = 4x106
M = 0.45
HEIGHT: 0.02c
PER UNIT SPAN
ONLY DRAG
ACCURATELY
MODELED
ACTUATOR ISSUES
•
DESIGN CONSIDERATIONS
•
•
•
•
•
SIZE CONSTRAINTS
TOTAL WEIGHT
FREQUENCY REQUIREMENTS
CENTRIFUGAL FORCES
ACTUATION METHODS UNDER CONSIDERATION
•
•
•
LINEAR DC ACTUATORS (VOICE COILS)
PIEZOELECTRIC
ROTARY/STEPPER MOTORS
VR-12 AIRFOIL
~14” CHORD
FLAP ACTUATION: AMPLIFIED PIEZO BENDER
Piezoelectric Bender
Mh
Fp
• TAPERED PIEZO BENDER
• LEVER AMPLIFIER
• REQUIREMENTS
• QUASISTATIC DISP. > 0.36”
• RESONANT FREQ
• > 20 Hz (4/rev)
• MODELS
• PIEZO BEAM FOR DISP.
• R-R FOR RESONANCE FREQ.
Coupler
LINEAR DC ACTUATORS
•
MOVING COIL (NCC)
– MORE FORCE
– HEAVIER
•
MOVING MAGNET (NCM)
– LESS FORCE
– LIGHTER
Motion
Motion
TESTING OF NCC ACTUATOR
- LASER VELOCIMETER USED
- BROADER FREQUENCY
RANGE NEEDED
CURRENT CONCEPT
•
•
•
•
CURRENT CONCEPT FOR NCC ACTUATOR
LOCATE AS FAR AFT AS POSSIBLE
SIMILAR DESIGN FOR THE NCM ACTUATOR
OPTIMAL DIMENSIONS NEEDED
ACTUATION DESIGN - IMMEDIATE FUTURE
•
•
•
•
•
•
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REFINE SIMULATION MODEL
BUILD PROTOTYPE OF NCC ACTUATOR
TEST NCM ACTUATOR
DEVELOP DESIGNS FOR OTHER ACTUATOR TYPES (i.e. PIEZO)
DETERMINE COMPARISON CRITERIA
DETERMINE OPTIMAL INPUT SIGNAL
DEVELOP METHODS TO TEST UNDER CF LOADS
ACCOMPLISHMENTS
•
•
•
•
•
WIND-TUNNEL MEASUREMENTS OF GURNEY FLAPS (2002)
CFD PREDICTION OF GURNEY FLAP PERFORMANCE (2003)
ACTUATION CONCEPTS EXPLORED (2002)
DYNAMIC CFD CALCULATIONS (2003-2004)
ROTOR PERFORMANCE ANALYSIS (2003-2004)
– INCLUDE DYNAMIC STALL MODEL
– CONSIDER UNSTEADY MiTE MODEL
•
•
INVESTIGATE MODELING UNSTEADY AERO. OF MiTES (2004)
MORE EXTENSIVE ACTUATION METHODS EXPLORED (2004-2005)
– LINEAR DC ACTUATORS
– PIEZOELECTRIC
2005-2006 PLANS
•
•
•
BUILD MODELS OF ACTUATION SYSTEMS
WIND-TUNNEL VERIFICATION OF ACTUATION METHODS
EXTEND ACTUATION DESIGN TO FULL-SCALE ROTOR BLADE
FUTURE RESEARCH NEEDS
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•
•
•
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DEVELOPMENT OF UNSTEADY AERO. MODELS FOR THE UPSTREAM
PLACEMENT OF MITES
DYNAMIC WIND-TUNNEL DATA
COMPREHENSIVE ROTOR PERFORMANCE / APPLICATION ANALYSES
HIGH-FREQUENCY ACTUATION DESIGN
MITE SPECIFIC AIRFOIL DESIGN
OTHER POTENTIAL BENEFITS OF MITES FOR ROTORCRAFT
PUBLICATIONS
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•
•
•
•
•
Maughmer, M., Lesieutre, G., Thepvongs, S., Anderson, W, Kinzel, M.,
“Miniature Trailing-Edge Effectors for Rotorcraft Applications”, AHS 59th
Forum, Phoenix, AZ, May 2003.
Kinzel, M., “Miniature Trailing-Edge Effectors for Rotorcraft Applications,”
Mindbend 2004 Student Conference, University Park, PA, April 2004.
Kinzel, M.P., “Miniature Trailing-Edge Effectors for Rotorcraft Applications,”
M.S. Thesis, Dept. of Aerospace Eng., Penn State University, University Park,
PA, 2004.
Kinzel, M.P, Maughmer, M.D, Lesieutre, G.L, Duque, E.P.N, "Numerical
Investigation of Miniature Trailing-Edge Effectors on Static and Oscillating
Airfoils," AIAA Paper No. 2005-1039, 2005.
Thiel, M., “Actuation of an Active Gurney Flap for Rotorcraft Applications,”
Mindbend 2005 Student Conference, University Park, PA, April 2005.
Maughmer, M., Lesieutre, G., Kinzel, M., “Miniature Trailing-Edge Effectors
for Rotorcraft Performance Enhancement”, AHS 61th Forum, Grapevine, TX,
June 2005.
SHORT TERM
LONG TERM
COMPLETE
MiTE SCHEDULE
TASKS
STAGE ONE
WT TEST WITH FIXED GURNEY FLAP
CFD SOLUTIONS (FLUENT)
MODEL ACTUATOR DESIGN
STAGE TWO
TRANSONIC CFD SOLUTIONS
ROTOR PERFORMANCE
SPECAILIZED CFD (OVERFLOW)
STAGE THREE
DEVELOP FULL SCALE ACTUATORS
DYNAMIC WT TESTING
2001
2002
2003
2004
2005 2006