RenaissanceRe Wall of Wind Research -- Moving Innovations from Theory to Applications by Arindam Gan Chowdhury, PhD Director, Laboratory for Wind Engineering Research, International Hurricane Research Center, Florida International University Hurricane Risk Mitigation Leadership Forum February 21 st, 2008
Wind Hazards
Current Wind Testing Methods Wind Tunnel Testing of Small Scale Models Dynamic Testing: Bridge Deck Section Model Static Testing: Model of Tall Building in Urban Area
Wall of Wind Full-Scale Hurricane Wind Simulation 1. Simulate Realistic Aerodynamic Effects of Complex Wind- Structure Interaction 2. Circumvent difficult scaling issues and test materials for the real structure 3. Test Components as an Integral part of the Mother Structure 4. Simulate Wind driven Rain to Study Water Infiltration 5. Test Structures to Failure and analyze Failure Modes 6. Test Structures under wide range of Wind Conditions in a Controlled Repeatable Environment
2-Fan Wall of Wind Portable Unit 120 mph H 2 O Injection
6- Fan RenaissanceRe Wall of Wind Stationary 130 mph H 2 O Injection Debris Injection
WoW, CFD, FMCP, RWDI, TTU FCMP DATA RWDI, WIND TUNNEL in Miramar WoW COMPUTATIONAL FLUID DYNAMICS (CFD) WERFL, TTU, FULL- SCALE
On-Going Investigations Correlation of Wind Speed to Damage Vortex Suppression Technologies Reduction of Water Intrusion Roof to Wall Connection Roof Top Equipment Roof Tiles Outreach
WoW Research Projects Vortex Suppression by Aerodynamic Edge Shapes (Patented / Patent Pending) Problem: Conventional roof corners and edges cause high suction load on roof due to flow separation and vortex formation WeatherPredict Consulting Inc. Contracted Validation Study
WoW Research Projects Vortex Suppression by Aerodynamic Edge Shapes (Patented / Patent Pending) Mitigation device to disrupt the conical vortices Drastically reduces the suction effects on flat-roof systems WeatherPredict Consulting Inc. Contracted Validation Study
WoW Research Projects Vortex Suppression by Aerodynamic Edge Shapes (Patented / Patent Pending) -20.0 Negative (Uplift) Pressure Coefficients by Configuration Cpmin -18.0-16.0-14.0-12.0-10.0-8.0 Original edge shape Conventional fascia DrainThru gravel stop AeroEdge screen -6.0-4.0-2.0 0.0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Tap Sequence Number WeatherPredict Consulting Inc. Contracted Validation Study
WoW Research Projects Mitigation of Wind Loads on Rooftop Equipment Problem: High damage rates and water filtration. Due to higher turbulence and pressure correlation, ASCE7-05 may increase loading by factor of 1.9
WoW Research Projects Mitigation of Wind Loads on Rooftop Equipment Single-story building located in Exposure c open terrain Difference in wind loading on rooftop equipment for a Cat 4 hurricane versus Cat 1 hurricane is 58%
WoW Research Projects Mitigation of Wind Loads on Rooftop Equipment Middle of Roof Leg 1 Axial Force Time History 0 0 20 40 60 80 100 120 140 160 180 200-50 -100-150 Middle of Roof Peak Axial Loads Force (lbs) -200-250 -300 Without Windscreen Windscreen 600-350 400 200-400 -450 Time (sec) Force (lbs) 0 1 2 3 4 5 6 Without Windscreen Windscreen -200-400 -600 Leg
WoW Research Projects Failure Progress of Clay-with-Foam Tile Roof System, 120 mph speed Concrete-with-Mortar Tile Roof System appeared to be the strongest system
WoW Facility Construction at FIU Engineering Campus
Institutional Strength Recognized Researchers Interdisciplinary team of experts consisting of wind, structural & mechanical engineers, architects, physical scientists, tropical meteorologists, and industry experts
Wall of Wind Publications Leatherman, S.P., Gan Chowdhury,, A., Robertson, C. J. (2007). Wall of Wind Full-Scale, Destructive Testing of Coastal Houses and Hurricane Damage Mitigation, Journal of Coastal Research,, 23 (5), p. 1211-1217. 1217. Gan Chowdhury,, A., Leatherman, S.P. (2007). Innovative Testing Facility to Mitigate Hurricane-Induced Losses, EOS, Transactions, American Geophysical Union,, 88 (25), pp. 262. Gan Chowdhury,, A., Simiu,, E., Leatherman, S.P. (2007). Hurricane Damage Mitigation of Coastal Houses. Proceedings of the 12th International Conference on Wind Engineering (Cairns, Australia), pp. 1975-1982.Florida 1982.Florida Division of Emergency Management Gan Chowdhury,, A., Simiu,, E., Lin, J., Leatherman, S.P. Wall of Wind FIU, The Wind Engineer, Newsletter of American Association for Wind Engineering (AAWE), October 2007. Gan Chowdhury,, A., Wall of Wind Hurricane Research at Florida International University, Applied Insurance Research (AIR), AIR Currents, August 2007.
Wall of Wind Media Events Discovery Channel (Canada) October 2007 USA Today August 2007 Wall Street Journal August 2007 ABC World News Tonight July 2007 NBC 6 October 2006
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