1 Alex Woods 2/6/08 Aerothermodynamics Group Cp and Cd Models

2 Cp and Cd models  Coefficient of Pressure –Used linear supersonic theory –Code scales with any given approximate geometry –Useful for determining locations of Center of Pressure, Drag values, Moments Group Name (i.e.Trajectory Optimization)

3 Drag Coefficients  Drag coefficient scales with starting axial force.  Drag increases approximately linearly for small aoa’s Group Name (i.e.Trajectory Optimization) Future Work  Integrate further aero codes into Master  Take part in MAT duties Chart by Alex Woods and Jayme Zott

4 References  Ashley, Holt, Engineering Analysis of Flight Vehicles, Dover Publications Inc., New York, 1974, pp  Anderson, John D., Fundamentals of Aerodynamics, Mcgraw-Hill Higher Education, 2001  Jayme Zott, for working with me, as well as her previous work with drag coefficients  Professor Colicott, in reference to linearized theory applications Group Name (i.e.Trajectory Optimization)

5 Backup Slides  Assumptions –Nose Cone may be modeled in two dimensions as a wedge –Adjacent stream lines vary with the cosine of the cylindrical angle from the windward radian –Drag coefficient scales upwards from Cd =.15 –Rocket diameter small enough to be considered within Linear Supersonic Theory

6 Drag Scaling with Angle of Attack  Drag should scale with aoa according to the equation: Cn is output from Cp code, while Ca is output by Jayme’s cd_m code.