COEUS UAV for Titan Brandon Adams Alex Hart Logan Sailer Ben Veenema

Project Goals Airframe to fit within current launch vehicles Aircraft mass less than 275-kg (Including payload) Cruise and maneuver within flight conditions 20-km 9-m/s 265-W Comparison versus current Titan exploration proposals

Project Objectives Choose optimized wing & body design for flight conditions Build aircraft or wing segment models for wind tunnel testing Rigorous aerodynamic and structural analysis Analysis of results, and comparison to alternative Titan proposals

Source: http://en.wikipedia.org/wiki/Titan_(moon) Dense atmosphere of hydrocarbons & other organic compounds Methane lakes and oceans Weather patterns similar to Earth Atmospheric interaction with high energy particles allows for the possibility of complex organic compounds, and potentially life Source: http://en.wikipedia.org/wiki/Titan_(moon)

Source: http://en.wikipedia.org/wiki/Titan_(moon) Flight Conditions 95% N2 - Ideal Gas Model Altitude [km]: Temperature [K]: Pressure [kPa]: Density [kg/m3]: Viscosity [N-s/m2]: Gas Constant [J/kg/K]: Speed of Sound [m/s]: Specific Heat Ratio: 20 76 48 2.16 4.84x10-6 296 178 1.4 Earth 20 216 5.529 0.0889 1.43x10-5 286 295 1.4 Source: http://en.wikipedia.org/wiki/Titan_(moon)

Design Considerations Low Temperature: Speed of Sound, Materials High Density Fluid: Lift, Drag, Power Low Velocity: Lift, Drag, Power Required vs. Available Power Launch Mass & Volume Constraints

Aerodynamics Velocity, mass, power requirements necessitates Lift-to-Drag (L/D) =12 Wingspan tends to be around 5-m Rigid power & lift requirements likely necessitate lifting body Reynolds numbers between 3.0x106 and 8.0x106

Temperature Carbon-fiber ply Negative coefficient of thermal expansion Impact tests at ~100 K

Launch, Delivery, & Structure Aircraft dimensions suggest Delta-IV Heavy for 5-m fairing Packaging in an aeroshell requires the wings and tail to be folded Source: http://marsairplane.larc.nasa.gov/platform.html

Summer Work Simplified Excel power and L/D curves Optimum velocity, power, and lift requirements cl & cd for varying span, aspect ratio Simple Xfoil models for NACA 3 & 4-series for Re between 3x106 and 5x106

Summer Work Minimum drag between 6- & 10-m span

Summer Work Xfoil pressure distribution

Summer Work MatLab model Relationship between power, span, aspect ratio Highlighted curve between 260 & 270 W

Summer Work Power asymptotically approaches ~4.4-m span

Next… Continue literature review (always…) Begin aerodynamic calculations & modeling – Earth vs Titan Explore & pursue wind tunnel experimentation Airfoil, body, and controls Materials, mass, and structure