Morphing Composites

Paul Weaver Stephen Daynes

www.bris.ac.uk/composites

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Morphing Composites - Weaver

Shape Adaptation: Requirements

load carrying

shapeadaptable

light

tooheavy

tooflexible

toostiff

lightweightstructures

compliantmechanisms

conventionalmechanisms

Example: [0n/90n]T

Unsymmetric Laminates

State 2

State 1

Morphing Composites - Weaver

Prestressed Laminates

400 mm

[0/90/90/0]THexcel 913GFRP prepreg1.1% Prestrain

Morphing Composites - Weaver

Bistable Flap Design

6× GFRP prestressed bistable laminates

Rear spar

Clamp + Foam seal

100 mm0 deg

10 deg

2× [0/90/0]T GFRP skins

Daynes, S., Weaver, P. M., Potter, K. D., and Hardick, M., U.K. Patent Application for a “Device Which is Subject to Fluid Flow,” No. 0902914.1, filed 20 Feb. 2009.

D-spar

Morphing Composites - Weaver

Wind Tunnel Demonstrator

7’ × 5’ Wind TunnelSpeed = 60 m/s; Re = 2.7 × 106

0 deg

10 deg

Morphing Composites - Weaver

Wind Tunnel Test

0 deg

10 deg

Morphing Composites - Weaver

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Morphing Air Scoop

• Morphing Air Scoop Design

• Finite Element Analysis

• Manufacture

• Exploitation

Morphing Composites - Weaver

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Morphing Air Scoop Design• 2 stable states (open & closed/flush)

• Smooth shape (‘NACA duct’)

• Deployment time < 5s

• ±10kPa dynamic pressure with deflections < ±2mm

• -20oC to +90oC

• Waterproof

• 10 year life (5000 cycles)

Ø60mm pipe to cooling system

Volume < 360×360×100mm

Intake area > 2750mm2

Underside

NACA duct

Morphing Composites - Weaver

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Morphing Air Scoop Design

Open Closed

Morphing Composites - Weaver

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Finite Element Analysis

• Tri-stable behaviour

• ABAQUS FE & analytical model agree

• Principal surface strains ± 1.4%

• ±1mm max deflection due to ±10 kPa

Morphing Composites - Weaver

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Manufacture

Envelope bag

Plastic mould

Tube Morphing plate

Top plate

Release film

Prepreg mould & drape

Autoclave manufacture

CFRP prepreg drape

Breather cloth

Morphing Composites - Weaver

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Exploitation

• Interaction with industrial partners to find applications.

• Concept not yet patent protected.

• Potential applications:– Deployable UAV engine air intakes

– Air intakes for aircraft cooling systems

– Automotive - Ventilation- Down force generation

Morphing Composites - Weaver