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Team 5 Vehicle Sizing PDR. Presented By: Trent Lobdell Ross May Charles Stangle. Outline. New Design Adjustments Weight Estimations Properties of the Wing Coefficient Estimations Resulting Constraint Diagram Final Constraint Diagram Specified Loading within Design Space
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Team 5Vehicle Sizing PDR Presented By: Trent Lobdell Ross May Charles Stangle
Outline • New Design Adjustments • Weight Estimations • Properties of the Wing • Coefficient Estimations • Resulting Constraint Diagram • Final Constraint Diagram • Specified Loading within Design Space • Final Numbers • Issues with given Code • Future Considerations AAE 451 – Team 5
New Design Adjustments • Reasons • Rough initial design had CG too far aft • AC was not behind CG • Reasonable aspect ratio • Shapelier wing section • Design adjustments suggested by customer AAE 451 – Team 5
Adjustments • Shortened booms • Decreased weight behind engine • Moved CG up • Pushed leading edge of wing back • Reduced wing area • Changed for better AR • AR Moved AC back and CG slightly forward AAE 451 – Team 5
Further Adjustments • Smaller tail section • Again, moved CG farther forward • Maintains appealing stealth theme AAE 451 – Team 5
Weight Estimation • Initial guess of 7.5 lbf from tables • Empty weight estimated at 6 lbf • Motor weight of 0.75 lbf • Energy density of batteries: 293040 joule/lbf • Guessed 3% battery weight fraction for take off and warm-up • Loiter time set at 30 min • Sizing code rendered a weight of: • 7.34 lbf AAE 451 – Team 5
Properties of the Wing • Wing Area • Counted the 3x3 inch blocks on final diagram • S = 900 in2 • Aspect Ratio • b = 5 feet wing span • AR = b2/S = 4 AAE 451 – Team 5
Coefficient Estimations • Drag Coefficients • 0.0025, 0.003, 0.0035 • Lift Coefficients • 1.0, 1.25, 1.5 • (CD1 with CL1) etc. AAE 451 – Team 5
Resulting Constraint Diagram with Flexible Values Design Space: Power Loading W/Bhp Wing Loading W/S AAE 451 – Team 5
Constraint Diagram With Moderate Values Design Space: CL = 1.25, CD = 0.003 AAE 451 – Team 5
Workin’ in the Design Space Power Loading W/Bhp Wing Loading W/S AAE 451 – Team 5
Known Vehicle Specifications • Weight = 7.34 lbf • Span = 60 in • AR = 4 • Wing Area = 900 in2 • Chosen Wing Loading = 0.165 lbf/in2 • Chosen Power Loading = 0.09 lbf/Bhp AAE 451 – Team 5
Issues With Code • Poorly commented • Hard to follow due to excess code • Did not function with the three inputs that it seemed to require (CL and CD) • Hashes needed adjustment Neo hates it, and you. AAE 451 – Team 5
Future Considerations • Implement energy consumption equations • Solidifying some of the numbers • Take off battery weight fraction • Warm-up battery weight fraction • Drag coefficient • Lift coefficient • L/D AAE 451 – Team 5
Doubts? Thoughts? Things left unsaid? AAE 451 – Team 5