Post on 24-Dec-2015
The Design and Development of an Active Smart Wing Model
ATAK Technologies
Team StructureTeam Structure Thomas AyersThomas Ayers
Project LeaderProject Leader Robert AguirreRobert Aguirre
Senior Testing Research SpecialistSenior Testing Research Specialist Kevin MackenzieKevin Mackenzie
Senior Modeling and Design SpecialistSenior Modeling and Design Specialist Vu TranVu Tran
Senior Research SpecialistSenior Research Specialist Dr. R. O. StearmanDr. R. O. Stearman
University of Texas Faculty ConsultantUniversity of Texas Faculty Consultant
Presentation OverviewPresentation Overview
Project ObjectivesProject Objectives Aerodynamic TheoryAerodynamic Theory Model DesignModel Design Model Testing OptionsModel Testing Options Project AccomplishmentsProject Accomplishments Recommended Future PursuitsRecommended Future Pursuits SummarySummary QuestionsQuestions
Project BackgroundProject Background ObjectivesObjectives TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
Randall BoldingRandall BoldingWrote a master’s thesis in 1978 Wrote a master’s thesis in 1978 in which a wing model was used in which a wing model was used to research the use of a to research the use of a stabilator as an active control to stabilator as an active control to suppress fluttersuppress flutter
Lockheed Martin CorporationLockheed Martin CorporationA research project on the A research project on the benefits that an active wing can benefits that an active wing can provide in contemporary provide in contemporary aircraft designaircraft design
High Airspeed BenefitsHigh Airspeed Benefits ObjectivesObjectives TheoryTheory Model Model TestingTesting WorkWork SummarySummary QuestionsQuestions
At high airspeeds normally At high airspeeds normally latent aerodynamic forces latent aerodynamic forces become powerful enough to become powerful enough to affect the flow about the airfoilaffect the flow about the airfoil
These changes cause torsional These changes cause torsional moments on the wingmoments on the wing
Theoretically, the use of active Theoretically, the use of active wing control on the leading wing control on the leading edge flaps and ailerons can be edge flaps and ailerons can be used in order to better control used in order to better control these latent aerodynamic forcesthese latent aerodynamic forces
Low Airspeed BenefitsLow Airspeed Benefits ObjectivesObjectives TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
At low speeds airflow about At low speeds airflow about the wing can separate from the wing can separate from the wing causing a “stall”the wing causing a “stall”
In natural flight, resonant In natural flight, resonant flapping is used to sustain flapping is used to sustain flight at low flight speedsflight at low flight speeds
Theoretically, oscillating the Theoretically, oscillating the wings by using the control wings by using the control surfaces would create high surfaces would create high lift conditions for short, low lift conditions for short, low airspeed maneuversairspeed maneuvers
Project ObjectiveProject Objective ObjectivesObjectives TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
To create an active wing To create an active wing model for the purpose of model for the purpose of defining relationships defining relationships between control surface between control surface oscillation and flight oscillation and flight performanceperformance
Aerodynamic TheoryAerodynamic Theory
Project ObjectivesProject Objectives Aerodynamic TheoryAerodynamic Theory Model DesignModel Design Model Testing OptionsModel Testing Options Project AccomplishmentsProject Accomplishments Recommended Future PursuitsRecommended Future Pursuits SummarySummary QuestionsQuestions
Desirable Flow TypesDesirable Flow Types BackgroundBackground TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
Attached-flow: Difference of the circulations of the upper and lower boundary layers create a lift force near a quarter chord of the airfoil. (figure a)
Detached-vortex-flow: rolled-up leading edge vortices create additional lift. (figure b)
[4]
Problems EncounteredProblems Encountered BackgrounBackgroun
dd TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
When a critical angle of attack achieved to create high lift, separated unsteady flow is unavoidable, and the vortices formed become uncontrollable once they leave the body.
Unsteady separation
Vortex shedding
Vortex breakdown
Separation ControlSeparation Control BackgroundBackground TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
To control separation, essentially the boundary vorticity flux control, a relationship between pressure, inertial, and viscous forces must be utilized.
Methods for controlling separation:
1) Control tangential pressure gradient: proper design of airfoil and wing geometry
2) Control skin friction field: modify local skin friction field near critical points
3) Introduce local movable wall: oscillating flaps
Reattachment ControlReattachment Control BackgroundBackground TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
When the boundary layer is already When the boundary layer is already separated, control of its reattachment separated, control of its reattachment is also feasible by utilizing unsteady is also feasible by utilizing unsteady excitations.excitations.
Example: Small leading-edge oscillating flap was Example: Small leading-edge oscillating flap was used to forced the shear layer separated from a used to forced the shear layer separated from a sharp leading edge to attach to just the sharp leading edge to attach to just the upstream of a round trailing edge, hence upstream of a round trailing edge, hence captured a strong vortex above a two-captured a strong vortex above a two-dimensional airfoil with angle of attack up to 27 dimensional airfoil with angle of attack up to 27 degree. Lift was increased by 60%.degree. Lift was increased by 60%.
[4][4]
Reattachment ControlReattachment Control BackgroundBackground TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
The inviscid vortex method can be used to compare flow patterns with or without leading-edge oscillation
Case (a) : leading-edge vortex moves downstream as new vorticies start to form. The leading edge vortex cuts off the trailing edge vortex sheet. The main vortex will eventually shed.
Case (b): main vortex is stabilized and stays close to the wing with nearly uniform vorticity distribution
[4]
Reattachment ControlReattachment Control BackgroundBackground TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
An additional example:An additional example:
Poly Vinylidence Flouride (PVDF) piezoelectric film was Poly Vinylidence Flouride (PVDF) piezoelectric film was used on the surface of a NACA 0012 airfoil to used on the surface of a NACA 0012 airfoil to generate surface oscillation through polarization generate surface oscillation through polarization changes in the materialchanges in the material
[5][5]Non-oscillated case: Max lift coefficient = 0.72, stall angle = 14 degreeNon-oscillated case: Max lift coefficient = 0.72, stall angle = 14 degree
Oscillated case: Max lift coefficient = 0.76, stall angle = 15 degreeOscillated case: Max lift coefficient = 0.76, stall angle = 15 degree
[5][5] [5] [5]
maxLC maxLC
Reattachment ControlReattachment Control BackgrounBackgroun
dd TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
For a highly swept wing, unsteady surface For a highly swept wing, unsteady surface excitations focus on delaying vortex excitations focus on delaying vortex breakdown, or can be used to maintain highly breakdown, or can be used to maintain highly concentrated and stable leading-edge vorticesconcentrated and stable leading-edge vortices
Schematic of mini-upper wing Schematic of mini-upper wing
[4][4]
Reattachment ControlReattachment Control BackgroundBackground TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
Mini-upper Wing:Mini-upper Wing:
The wing has a larger incidence The wing has a larger incidence than the main wing, thus than the main wing, thus forcing the flow below it to forcing the flow below it to converge. This implies an converge. This implies an additional axial acceleration at additional axial acceleration at the vortex core, and therefore the vortex core, and therefore delays its burst. However, the delays its burst. However, the applicable angle of attack is applicable angle of attack is limited, due to limitations limited, due to limitations created by the wing designcreated by the wing design
Model DesignModel Design
Project ObjectivesProject Objectives Aerodynamic TheoryAerodynamic Theory Model DesignModel Design Model Testing OptionsModel Testing Options Accumulated Project WorkAccumulated Project Work Recommended Future PursuitsRecommended Future Pursuits SummarySummary QuestionsQuestions
Actuator DesignsActuator Designs BackgroundBackground TheoryTheory ModelModel WorkWork SummarySummary QuestionsQuestions
Hydraulic ActuatorHydraulic Actuator
Electromechanical Electromechanical ActuatorActuator
Electric MotorElectric Motor
Benefits of ATAK’s Benefits of ATAK’s DesignDesign
ObjectivesObjectives TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
Size of Control SystemSize of Control System – Electric – Electric motor and shaft will be half the size of the previous groups
Ease of Operation – Does not require understanding of complex controller
Able to Test – By taking wind tunnel dimensions into account when designing we make sure that we will be able to mount the wing in order to obtain Cl and Cd measurements
Flexibility – Leading and trailing edge flaps will be able to oscillate. Will be able to control angle of deflection and phase between flaps
Model DesignModel Design
Overall Model Assembly
ObjectiveObjectivess
TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionQuestion
ss
Model DesignModel Design
Wing Spar, Engine and Rods
ObjectiveObjectivess
TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionQuestion
ss
Model DesignModel Design
Gearing Assembly
ObjectiveObjectivess
TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionQuestion
ss
Model DesignModel Design
Bevel Gears
ObjectiveObjectivess
TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionQuestion
ss
Model DesignModel Design
Actuation System – Push/Pull Rods
ObjectiveObjectivess
TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionQuestion
ss
Model DesignModel Design
Actuation System including Control Surfaces
ObjectiveObjectivess
TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionQuestion
ss
Model DesignModel Design
Wing Model Without Modified Control Surfaces
ObjectiveObjectivess
TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionQuestion
ss
Model DesignModel Design
Wing Model With Deflected Control Surfaces
ObjectiveObjectivess
TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionQuestion
ss
Model DesignModel Design
Overall Model Assembly
ObjectiveObjectivess
TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionQuestion
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Model Testing OptionsModel Testing Options
Project ObjectivesProject Objectives Aerodynamic TheoryAerodynamic Theory Model DesignModel Design Model Testing OptionsModel Testing Options Accumulated Project WorkAccumulated Project Work Recommended Future PursuitsRecommended Future Pursuits SummarySummary QuestionsQuestions
BackgroBackgroundund
TheoryTheory ModelModel TestingTesting WorkWork SummarSummar
yy QuestionQuestion
ss
Model Testing GoalsModel Testing Goals
Take next step in project Take next step in project developmentdevelopment
Obtain and reduce dataObtain and reduce data
Conduct repeated tests to ensure Conduct repeated tests to ensure quality data acquiredquality data acquired
Testing Data AcquisitionTesting Data Acquisition BackgroBackgro
undund TheoryTheory ModelModel TestingTesting WorkWork SummarSummar
yy QuestionQuestion
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Relationship between oscillation Relationship between oscillation frequency and frequency and Variations of coefficient of liftVariations of coefficient of lift Pressure distributions over wingPressure distributions over wing Wing spar strainWing spar strain Wing tip flutterWing tip flutter
Relationships can be used to find Relationships can be used to find optimum frequencies foroptimum frequencies for Maximizing coefficient of liftMaximizing coefficient of lift Minimizing wing spar strainMinimizing wing spar strain Minimizing wing tip flutterMinimizing wing tip flutter
Model Testing Model Testing EquipmentEquipment
BackgroBackgroundund
TheoryTheory ModelModel TestingTesting WorkWork QuestionQuestion
ss SummarSummar
yy
Smoke wireSmoke wire
Pressure tapsPressure taps
Strain GaugesStrain Gauges
Accelerometer Accelerometer
Model Testing Model Testing SuggestionsSuggestions
BackgroBackgroundund
TheoryTheory ModelModel TestingTesting WorkWork SummarSummar
yy QuestionQuestion
ss
Modify model as neededModify model as needed
Start testing as soon as possibleStart testing as soon as possible
Be familiar with theory and Be familiar with theory and equations needed to reduce dataequations needed to reduce data
Project AccomplishmentsProject Accomplishments
Project ObjectivesProject Objectives Aerodynamic TheoryAerodynamic Theory Model DesignModel Design Optional Testing ProceduresOptional Testing Procedures Project AccomplishmentsProject Accomplishments Recommended Future PursuitsRecommended Future Pursuits SummarySummary QuestionsQuestions
Project AccomplishmentsProject Accomplishments ObjectiveObjective
ss TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
Project has been advanced over Project has been advanced over the past four termsthe past four terms
The Active Wing Group (AWG)The Active Wing Group (AWG)
Active Wing Technology (AWT)Active Wing Technology (AWT)
Active Wing Engineering (AWE)Active Wing Engineering (AWE)
ATAK Technologies (ATAK)ATAK Technologies (ATAK)
Active Wing GroupActive Wing Group ObjectivesObjectives TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
Recovered F-111 wing-tail Recovered F-111 wing-tail from storagefrom storage
Investigated limit cycle Investigated limit cycle oscillations (LCO)oscillations (LCO)
Provided a strong foundation Provided a strong foundation for Summer 2002 project for Summer 2002 project continuationcontinuation
Active Wing Active Wing TechnologiesTechnologies
ObjectiveObjectivess
TheoryTheory ModelModel TestingTesting WorkWork SummarSummar
yy QuestionQuestion
ss
Primarily Research on F-111Primarily Research on F-111
Limit cycle oscillations (LCO)Limit cycle oscillations (LCO)
Increasing lift on fighter Increasing lift on fighter wingswings
Implementation of control Implementation of control surfacessurfaces
Digital and analog control Digital and analog control systemssystems
Researched the aerodynamic Researched the aerodynamic theory behind oscillating flapstheory behind oscillating flaps
Selected actuation systemSelected actuation system
Constructed model wing with Constructed model wing with leading edge flapsleading edge flaps
ObjectivesObjectives TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
Active Wing EngineeringActive Wing Engineering
ATAK TechnologiesATAK Technologies ObjectivesObjectives TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
ResearchResearchAerodynamic forces involved in active wing Aerodynamic forces involved in active wing
technologytechnologyControl surface effect on liftControl surface effect on lift
Model DesignModel DesignActuation systemActuation systemStructure designStructure designAutoCAD model AutoCAD model
Delivered spar design to machinist Delivered spar design to machinist for constructionfor construction
Gathered all necessary model Gathered all necessary model materials.materials.
Lab MaintenanceLab MaintenanceWorked to clean WRW 316Worked to clean WRW 316
ATAK TechnologiesATAK Technologies
Wing Structure
ObjectiveObjectivess
TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionQuestion
ss
Recommended Future Recommended Future PursuitsPursuits
Project ObjectivesProject Objectives Aerodynamic TheoryAerodynamic Theory Model DesignModel Design Optional Testing ProceduresOptional Testing Procedures Project AccomplishmentsProject Accomplishments Recommended Future PursuitsRecommended Future Pursuits SummarySummary QuestionsQuestions
Recommended Future Recommended Future PursuitsPursuits
ObjectivesObjectives TheoryTheory ModelModel TestingTesting WorkWork SummarySummary QuestionsQuestions
Complete the construction of the Complete the construction of the wing modelwing model
Prepare for experimentation using Prepare for experimentation using the modelthe model Design testing equipment and conditionsDesign testing equipment and conditions Place instruments on model designPlace instruments on model design Use LabView software to coordinate Use LabView software to coordinate
data acquisitiondata acquisition Conduct experiments using wing Conduct experiments using wing
modelmodel Reduce acquired data and draw Reduce acquired data and draw
conclusions concerning the conclusions concerning the relationship between frequencies relationship between frequencies and the desired characteristics.and the desired characteristics.
Presentation SummaryPresentation Summary
Background InformationBackground Information Project ObjectivesProject Objectives Aerodynamic TheoryAerodynamic Theory Modeling and Final DesignModeling and Final Design Proposed Testing ProceduresProposed Testing Procedures Project AccomplishmentsProject Accomplishments Recommended Future WorkRecommended Future Work
ReferencesReferences[1][1] Aguirre, Robert, Thomas Ayers, Kevin Aguirre, Robert, Thomas Ayers, Kevin Mackenzie, Mackenzie,
and Vu Tran. “Design and Development of an Active Wing and Vu Tran. “Design and Development of an Active Wing Model.” ATAK Technologies, Austin, TX, Mar. 2003.Model.” ATAK Technologies, Austin, TX, Mar. 2003.
[2][2] Garret, Carlos, Justin Gray, and Kevin Garret, Carlos, Justin Gray, and Kevin Marr. Marr. “Design of an Active Controlled Wing Model Using Flap “Design of an Active Controlled Wing Model Using Flap Oscillation.” AWE Engineering, Austin, TX, Dec. 2002.Oscillation.” AWE Engineering, Austin, TX, Dec. 2002.
[3][3] Fuentes, David, Basil Philips, and Naoki Sato. “Design Fuentes, David, Basil Philips, and Naoki Sato. “Design and Control Modeling of an Active Variable Geometry Wing.” and Control Modeling of an Active Variable Geometry Wing.” Active Wing Technologies, Austin, TX, Aug. 2003.Active Wing Technologies, Austin, TX, Aug. 2003.
[4] Wu, J.M., Wu, J.Z., “Vortex Lift at a Very High Angle of Attack [4] Wu, J.M., Wu, J.Z., “Vortex Lift at a Very High Angle of Attack with Massively Separated Unsteady Flow,” with Massively Separated Unsteady Flow,” Fluid Dynamics of Fluid Dynamics of High Angle of AttackHigh Angle of Attack, R. Kawamura, Y. Aihara ed., Springer-, R. Kawamura, Y. Aihara ed., Springer-Verlag, Berlin Heidelberg, 1993, pp. 35-63.Verlag, Berlin Heidelberg, 1993, pp. 35-63.
[5] Kobayakawa, M., Kondo, Y., Suzuki, H., “Airfoil Flow Control [5] Kobayakawa, M., Kondo, Y., Suzuki, H., “Airfoil Flow Control at High Angle of Attack by Surface Oscillation,” at High Angle of Attack by Surface Oscillation,” Fluid Fluid Dynamics of High Angle of AttackDynamics of High Angle of Attack, R. Kawamura, Y. Aihara , R. Kawamura, Y. Aihara ed., Springer-Verlag, Berlin Heidelberg, 1993, pp. 265-273.ed., Springer-Verlag, Berlin Heidelberg, 1993, pp. 265-273.
Questions?