Thesis SeminarDAVID S. MARTIN – 3/2/2017

Presentation OverviewI. Background

II. Previous Work

III. Project Goals

IV. Project Workflow

V. Work So Far

VI. Remaining Tasks

VII. Future Studies

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Background

• To date, studies of winglet design have not accurately replicated avian wingtip geometry – pelican wings, forexample

• Studies detailing the effectiveness ofdistributed, “cascading” winglets at reducing drag typically have yielded mixed results using highly simplifiedgeometries

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Still from video footage provided by the BBC

Previous Work

• Studies to determine dragreduction of a single vortex vs.smaller distributed vortices created at the wing tip have generally been inconclusive or contradictory

• Minimal biomimicry present

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Example - Coiro et al.• Series of studies performed by Coiro, Nicolosi, Scherillo

and Maisto (2007, 2008)

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Project Goals1. Use 3D scanning and 3D printing technologies to develop a process to

create a biologically accurate aerodynamic test model of a Brown Pelican wing

2. Fabricate a wind tunnel test model to validate the model creation process

3. Characterize sections of a 3D scanned pelican wing and compare to previous studies

4. Perform wind tunnel testing using Cal Poly’s low speed wind tunnel

◦ Smoke and laser visualization

◦ Pressure measurement

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(e) Wing grid

Coiro et al.Nazarinia et al.

Project Workflow

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Obtain 3D Scan Data

Import 3D Scan Data Into CAD

and Refine

3D Print Models and Improve

Surface Finish

Perform Wind Tunnel Testing

Analyze and Compile Data

Work So Far - 3D Scanning• 3D scans of:• Pelican primary feather – Santa Barbara Museum of Natural History

• Pelican wing – Los Angeles Natural History Museum

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MATLAB• MATLAB code developed to create sections from raw point cloud 3D

scan data

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3D Modeling• MATLAB sections used to recreate simplified wing and feather shapes

from scratch

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Airfoil CharacterizationBrown Pelican (Pelecanus occidentalis), left wing

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Section 1 (proximal)

Section 3

Section 5

Section 7 Section 15 (distal)

Section 13

Section 11

Section 9

3D Printing• Initial small-scale prototype created to

troubleshoot the preliminary model creation process

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Lessons Learned• ABS was not suited to this application,

new material required

• Surface finishing techniques needed refinement

• Smoke machine output wasinconsistent

• 1:1 scaling not currently possiblewith available technology

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Final Test Model

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Remaining Tasks• Finish airfoil characterization

and comparison

• Continue wind tunnel testing:

o Smoke and laser visualization

o Pressure rake

o Investigate feather deflection

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Future Studies• Establishing a process to create biologically accurate wing models opens the door to numerous possibilities:

o Different primary feather configurations

o Different surface textures

o Other birds (California Condor,Australian Pelican, Turkey Vulture)

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California Condor (Gymnogyps californianus)

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References• Slide 1: Graham Doig, www.thinkflip.net

• Slide 3: https://www.fws.gov/lab/featheratlas/images/SpreadWing.jpg

• Slide 4: http://cdn-www.airliners.net/photos/airliners/9/4/8/1041849.jpg?v=v40

• Slide 5: Coiro, Nicolosi, Scherillo, Maisto, “Single Versus Multiple Winglets: Numerical and Experimental Investigation,” ICAS 2008, 26th International Congress of the Aeronautical Sciences.

•Slide 7: Coiro, Nicolosi, Scherillo, Maisto, “Single Versus Multiple Winglets: Numerical and Experimental Investigation,” ICAS 2008, 26th International Congress of the Aeronautical Sciences.

Nazarinia, Soltani, Ghorbanian, “Experimental Study of Vortex Shapes Behind a Wing Equipped With Different Winglets,” JAST 2006, Vol. 3 No. 1, pp 1-15.

• Slide 21: https://s-media-cache-ak0.pinimg.com/736x/9f/42/54/9f4254b6d73fad25c432a5f46c748a18.jpg

• Slide 22: http://cdn.pcwallart.com/images/pelican-flying-sunset-wallpaper-1.jpg

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