1. P14414Arborloo Wind Resistance Test Stand
Final Presentation
13 May 14

2. Overview Team Introduction Project Objectives
Customer/Engineering Requirements
Systems Architecture
Theory
CFD Analysis
Design
Results
Project Improvements & Recommendations
MSD Assessment

3. Team Introduction

4. Project Objectives
Design a test stand to determine the wind resistance of various scale model arborloo designs
Provide information about the forces experienced by an arborloo during a Class I hurricane
Allow for safe testing of various arborloo sizes, shapes, and materials
Team should create a set-up for testing, devise a test procedure, and provide recommendations for the optimal arborloo shape and design based on testing results

5. Customer Requirements

6. Engineering Requirements

7. System Architecture

8. Theory CD – Drag Coefficient
The drag coefficient is a dimensionless parameter that characterizes an object's resistance to fluid flow and allows for direct comparison of aerodynamic effects on different shapes.
For certain shapes, the Coefficient of Drag stays constant independent of Reynolds Number. In the case of the team’s first prototype, which can be treated as a flat plate, the CD will stay constant for all Re larger than 1000.

9. CFD Analysis

10. Design Utilizes existing wind tunnel base
2 x Clippard EMC-12 pressure scanner
Omega PX277 pressure transducer
JR3 load cell
National Instruments NI_USB-6008 DAQ
Fabricated flange to accommodate existing shaft, base & wires
Test Arborloo designed with ¼” PVC sheets

11. Final Design

12. Testing Testing Procedures Document <20 mins entire testing
Automated Results plotting using MATLAB

13. Results

14. Results
The force exerted on an arborloo by 95 mph winds is at the very best 415 lbf (CD = 1) and at worst 830 lbf. (CD = 2)
Comparable to two male gorillas (330 lbf) sitting on face of the arborloo
The pressure distribution shows that a larger stress is applied to the arborloo closer to the ground
Pressure distribution similar to that seen in CFD, better resolution w/ more pressure taps

15. ER Revisited

16. Project Improvements/Recommendations
Better understand the blockage effects in wind tunnels
Future teams should use CFD and empirical results to determine correction factor
Recommendations:
It is clear from the collected data and knowledge of hurricane conditions, that the best way to ensure that the structure would not be destroyed is if the structure can be easily disassembled and stored away.

17. MSD Assessment
Model MSD as a job search? Students bid on existing projects and interview w/ guide or cust. “What skill-set can you bring to the table?”
Do not waste MSD I time with presentations, MSD I should be primarily working time as that’s when everyone is most motivated. Presentations were not helpful.
MSD I was a little slow, long lead times for some small deliverables

18. Acknowledgments Special Thanks To: Sarah Brownell Dr. Thorn
Prof. Wellin
Dr. Venkataraman
Plastic and Concrete Design Teams
Pedro Cruz Dilone

19. Questions?