Nanotechnology in Aerospace Jenni BeetgeBlas Quiroga

Outline

1. Summary2. Background and motivation3. Basic Principles4. Recent advances5. Assessment6. Further research

Summary• Increased speed causes aerodynamic heating• Challenges

• Material structure and composition• Cost• Safety, stability, control

• Solutions• Composites & flame resistant layers• Shape memory• Micro-scale devices• Computational fluid dynamics

• Limitations• Nanocomposite quality• Durability

Background and motivation• Main objectives in aircraft design:• Douglas DC-3 (1930’s) mission: To fly more passengers

safely and comfortably at a faster speed and lower cost than any existing airliner

• Nanotechnology applied to optimize:• strength• flexibility• lightweight• safety• controllability, stability• availability (cost) • flame resistance • structural integrity• low observable characteristic (stealth)

Basic Principles• Air drag aerodynamic heating• Flame resistance

• Structure dictated by purpose, with inherent limitations• Wing sweep (forward or back) – swept-forward reduces transonic

drag (desirable) but causes structure failure • Material strength and elasticity

• Limited performance caused by fixed structure• Different stages of flight require different structures for optimum

performance • Safety constraints on speed and cost

SR71 Blackbird (1960s)• High speed (1 mile in 2 seconds) Heating• Average body temperature: 600°F• Body material expansion (3-4 inches in length)• Composed of 93% titanium alloy and composites

• Iron nanoparticle paint (60lbs)• increased thermal emissivity at high speed and dissipation of

electromagnetic radiation

• Challenge: Operational cost• Silicon used to seal the seams had to be stripped and new

material reapplied every 100 flight hours because of aerodynamic heating

Recent advances (2000’s)•Morphing air vehicles:• Reconfiguration of wingspan, wing area and wing

sweep• Reduces fuel consumption, vibration and improves

control • Some methods:• Shape memory polymer softens when heated, reshaped, and

set within seconds of after heating (small flexible heaters embedded inside wing material) – Developed by Lockheed-Martin

• Expanded performance envelope

Micro air vehicles• Purpose:• Sensing of• Bio-agents• Chemical compounds• Nuclear materials• Anti-crime and counter-terrorism surveillance

• Computational fluid dynamics • Low Reynolds number of surrounding airflow

PMC’s and flame resistance• Polymer matrix composites (PMC’s):• High strength and modulus, good fatigue and corrosion resistant• Challenge: Polymer matrix degradation (heat, fire)• Solution: Coating with carbon nanofiber-based nanopaper

produces a fast forming char layer• Char layer provides protection to mass loss and heat release

Computing• Unstable airplane flown by computer • use quantum computing when faster reaction is required while

maintaining performance not slowed down by the need to manually control

• Unmanned combat air vehicles • to run simulations to find best course of action

• enemy weakness exploited

Conventional solar cells• Light absorbed by a semiconductor producing electron hole• Separated by internal electric field• Flow of electrons and holes creates current• e-h pair requires that the photons of light have energy exceeding

the bandgap of the material• higher energy photons are relatively inefficient• loses its energy through collisions with the lattice• most photon energy is lost into heat• 31% efficient

Quantum Dot cells• Changing particle size controls eletrical, optical and thermal

properties• Ability to tune the bandgap• Efficient• improved radiation tolerance and temperature coefficients• improved performance of thin film photovoltaics• bandgaps that can be tuned into the far infrared• Easier to make, simpler and cost-effective

Quantum computing• harness the power of atoms and molecules to perform

memory and processing tasks• perform certain calculations significantly faster than any

silicon-based computer• Richard Feynman in 1982• Modeled by the Quantum Turing machine• Maintains a sequence of qubits• Qubit can be either a 1, 0 or any superposition state• Controlled initial state• Ends calculation with measurement of all states

Limitations • Quantum Dot cellso Materials are expensiveo Pre-commercialization stageso constrained to the rigid materials properties

• Quantum computingo Still in it’s infancyo Quantum decoherenceo Wont go past 16 qubits

Recommendations• Quantum dot cells• Find a way to produce a double layer cell

• Quantum computing• Find ways to implement qubits into common technology like

phones, TV’s, etc.• Start using for calculations it can perform

Further research• SR-71A Blackbird• Out of service: Requires advances in nanotechnology to develop

heat tolerant, low cost material and durable sealant • PMC’s• Next challenge: limited quality of nanocomposites -

hinders homogeneous dispersion of nanoparticles

• Thin film amorphous silicon solar cells

• Thin film, flexible polymeric solar cells incorporating quantum dots or carbon nanotubes

• Enhance the performance of the current SOA space solar cells

References• J. Zhuge et al. Fire retardant evaluation of carbon nanofiber/graphite nanoplatelets,

nanopaper-based coating under different heat fluxes. ELSEVIER. Composites: Part B 43 (2012) 3293–3305.

• "Introduction to Flight 7th Edition." Introduction to Flight 7th Edition by Anderson. N.p., n.d. Web. 18 Oct. 2012. <http://www.chegg.com/textbooks/introduction-to-flight-7th-edition-9780073380247-0073380245>.

• http://www.marchfield.org/sr71a.htm• https://rt.grc.nasa.gov/power-in-space-propulsion/photovoltaics-power-technologies

/technology-thrusts/nanomaterials-and-nanostructures-for-space-photovoltaics/• "Quantum computing: its nature and its applicable usage in aerospace industry",

Proc. SPIE 5866, The Nature of Light: What Is a Photon?, 84 (August 04, 2005); doi:10.1117/12.618117; http://dx.doi.org/10.1117/12.618117

• http://www.fastcursor.com/computers/quantum-computer-photo-gallery.asp• "Mn

-Doped Quantum Dot Sensitized Solar Cells: A Strategy to Boost Efficiency over 5%.". J. Am. Chem. Soc., 2012, 134 (5),. pp. 2508–2511. doi:10.1021/ja211224s

• Shockley, William; Queisser, Hans J. (1961). "Detailed Balance Limit of Efficiency of p-n Junction Solar Cells". Journal of Applied Physics 32: 510. Bibcode 1961JAP....32..510S. doi:10.1063/1.1736034

• H. Sargent, E. (2005). "Infrared Quantum Dots". Advanced Materials 17: 515. doi:10.1002/adma.200401552

Questions?