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SSA Phase II Final Report.Book

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SSA Phase II Final Report.Book Solid State Aircraft Phase II Project NAS5-03110 Final Report Prepared for: Robert A. Cassanova, Director NASA Institute for Advanced Concepts May 31, 2005 Table of Contents Table of Contents List of Tables .............................................................................................................. iii List of Figures ............................................................................................................. v List of Contributors .................................................................................................. xv Executive Summary ................................................................................................ xvii Chapter 1.0 Introduction ............................................................................................ 1 1.1 SSA Concept Description ..........................................................................................................1 1.2 Flapping Wing Flight ..................................................................................................................4 1.2.1 Insect Flight .........................................................................................................................5 1.2.2 Bird, Mammal and Dinosaur Flight ......................................................................................8 1.2.3 Wing Shape .......................................................................................................................12 1.3 Mission Capabilities .................................................................................................................15 1.3.1 Operation on Earth ............................................................................................................16 1.3.2 Operation on Venus ..........................................................................................................23 1.3.3 Operation on Mars ............................................................................................................29 1.3.3.1 Imagery ...................................................................................................................29 1.3.3.2 Magnetic Field Mapping and Investigation .............................................................31 1.3.4 Near Infrared and Neutron Spectroscopy .........................................................................33 1.3.5 Radar Sounding ...............................................................................................................34 1.3.6 In-situ Atmospheric Science ..............................................................................................34 Chapter 2.0 SSA Configuration and Operation ...................................................... 37 2.1 Wing and Fuselage Material Development .............................................................................37 2.1.1 IPMC Development Background .......................................................................................39 2.1.2 General Considerations on IPMC as SSA Wing Material .................................................40 2.1.3 IPMC Manufacturing Techniques ......................................................................................42 2.1.4 Three-dimensional Fabrication of SSA Wing Material ......................................................47 2.1.5 Electrical Performance ......................................................................................................51 2.1.6 Thermodynamic Efficiency ................................................................................................53 2.1.7 Force Density for SSA Wing Materials ..............................................................................55 2.1.8 Cold Temperature Properties of IPMC For High Altitude and Planetary Applications ......56 2.1.9 Modeling and Simulation ...................................................................................................63 2.2 Thin Film Batteries ...................................................................................................................77 2.3 Thin Film Array .........................................................................................................................81 2.3.1 Introduction .......................................................................................................................81 2.3.2 How a Solar Cell Works ....................................................................................................81 2.3.3 State-of-the-art Thin Film Solar Cells ................................................................................83 2.3.4 Near Term Advancements for Thin film Solar Cell Technology ........................................84 2.3.5 Long-term Advancements for Thin Film Solar Cell Technology ........................................85 Chapter 3.0 Operational Environments .................................................................. 87 3.1 Environmental Conditions for Flight on Venus .....................................................................87 3.2 Environmental Conditions for Flight on Earth .......................................................................95 3.2.1 East Coast Wind Profiles ................................................................................................104 3.2.2 West Coast Wind Profiles ...............................................................................................104 3.3 Environmental Conditions for Flight on Mars .....................................................................107 3.3.1 Physical Properties .........................................................................................................109 3.3.2 Atmospheric Conditions ..................................................................................................110 3.3.3 Dust Storms and Wind ....................................................................................................113 Chapter 4.0 SSA Design and Feasibility Analysis ............................................... 117 4.1 Aerodynamic Design and Analysis .......................................................................................117 4.1.1 Previous Work on Flapping Flight Aerodynamics ...........................................................117 4.1.2 Two-dimensional Airfoil Analysis .....................................................................................121 i Solid State Aircraft 4.1.2.1 Circular Arc CFD Airfoil Evaluation for SSA ......................................................... 140 4.1.3 Turbulent Flow Simulations at Rec = 100,000 ................................................................ 144 4.1.4 Performance of a Two-dimensional Pitching and Plunging Airfoil for a Solid State Aircraft . 150 4.1.4.1 Analysis ............................................................................................................... 150 4.1.4.2 Numerical Simulation of Plunging/Pitching Airfoil ................................................ 151 4.1.4.3 Results ................................................................................................................. 153 4.1.5 Experiments Using Flapping Wing Model ....................................................................... 157 4.1.5.1 Wing Motion ......................................................................................................... 158 4.1.5.2 Flapping ............................................................................................................... 159 4.1.5.3 Encoder ................................................................................................................ 159 4.1.5.4 Flapping-Only Wing Motion .................................................................................. 163 4.1.5.5 Reynolds Number ................................................................................................ 163 4.1.5.6 Force Measurements ........................................................................................... 163 4.1.5.7 Noise Filtering ...................................................................................................... 167 4.1.5.8 Directions of Lift and Drag .................................................................................... 167 4.1.5.9 Estimating Tangential Force ................................................................................ 168 4.1.5.10 Flow Visualization .............................................................................................. 169 4.1.5.11 Experimental Results ......................................................................................... 172 4.1.5.12 Forces on the Wing ............................................................................................ 172 4.1.6 Technology Roadmap - Aerodynamic Analysis .............................................................. 176 4.1.6.1 Future Computer Simulations .............................................................................. 176 4.1.6.2 Experiments on Flapping Wings .......................................................................... 176 4.1.6.3 Aerodynamic Stability Analysis ............................................................................ 177 4.1.6.4 Scale-model Demonstrator - Flight Tests ............................................................. 177 4.1.7 Quasi-steady, Blade Element Analysis of Flapping Wing Motion ................................... 177 4.1.7.1 Quasi-steady Analysis .........................................................................................
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