AAE 450 Spring 2008 Vince Teixeira 7 February 2008 Structures Nose Cone Design/Heating Analysis

AAE 450 Spring 2008 Structures Heat Analysis  Stagnation-Point Heat- Transfer Rate –Ref: Methods for Analysis of Spacecraft Preliminary Design by Prof. Steven P. Schneider –Uses velocity profile provided by Trajectory code ver 3.2 –Code help from Jason Darby (Aerothermodynamics) –Heating rate at stagnation point is a function of wall enthalpy to total enthalpy –Heating rate integrated over time will be used to determine maximum temperature of nose cone

AAE 450 Spring 2008 Structures Nose Cone Model  CATIA model uses power-law body to determine mass/Inertia matrix for specific materials –Input: Nose radius (r n ) and material properties Future Work  Expand code to determine temperature of nose cone during ascent –Will determine thickness/mass of nose cone needed  Test CAD model under pressure loads

AAE 450 Spring 2008 Structures Backup Slides – Heating Analysis

AAE 450 Spring 2008 Structures Backup Slide – CATIA Measurement  CATIA provides: –Volume –Area –Mass –Center of Gravity coords. –Inertia Matrix Inc. Principal axes and products of inertia –Spline length  For a material with specified properties

AAE 450 Spring 2008 Structures Backup Slides – Mass/Inertia Matrix MaterialMassI xx I yy I zz Ti4.71 kg0.238 kg-m kg-m 2 Steel8.301 kg0.419 kg-m kg-m 2 Al2.862 kg0.145 kg-m kg-m 2 Mg1.899 kg0.096 kg-m kg-m 2 Center of Gravity located at 64% of nose cone length (0.64*L) - Measured from nose cone tip

Backup Slides - Equations  Power-law body:  Absolute velocity:  Total enthalpy:  Heating Rate: AAE 450 Spring 2008 Structures

AAE 450 Spring 2008 Structures References  Schneider, Steven P., “Methods for Analysis of Preliminary Spacecraft Design,” AAE 450, Spacecraft Design, Purdue University  Trajectory code written by Trajectory group  Stagnation heating code written by Jason Darby and Vince Teixeira