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Numerical and Wind-TunnelSimulation of Wind Loads onSmooth and Rough Domes
R.N. Meroney
C.W. LetchfordP.P. Sarkar
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Powerpoint Presentations!
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Structural Domes
Domes are commonly used to encloselarge spaces because of their structuralefficiency and economic benefit.
Domes are excellent at resistingsymmetric loading, but
Asymmetric loading may causestructural distress and failure.
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Domed Sports Halls & Stadiums
HoustonAstrodome
Hubert H. HumphreyMetro-Dome, Min
Little Sports Palace, Rome
Pepsi Center, Denver
Sun Dome, Fukui, Japan
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Assembly Hall Dome
Assembly Hall, U. ofIllinois Urbana/Champ
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Domed PublicBuildings
^ Public Exhibition HallsMillennium Dome, London,320 m diameter, 80,000 sq m
floor space
Museums and Halls,Barlow Planetarium, CA
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Inflated Domes
US Pavilion, OsakaExposition 1970
Carrier Stadium,Syracuse University
Georgia Dome, Atlanta Silverdome, Pontiac, MI
RCA (Hoosier) Dome
Indianapolis, IN
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Inflated Domes (contd)
Tokyo DomeBig Egg Stadium,
Tokyo, Japan
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Bulk Storage: Dust Supression, Waterand Wastewater Treatment Covers
Temcor Aluminum DomesTriangulated space truss system with
triangulated panels
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Bulk Storage: Coke Piles
Pittsburgh, CA Marine Terminal Coke Storage DomesThree 55 m (180 ft) diameter hemispheres
Los Angeles, CA Export Terminal Coke Storage Domes ConstructionTwo 73 m (240 ft) diameter hemispheres, Shotcrete applied to interior
of inflated airform mounted on footer and stem wall
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Rough Surface Hemispheres
Sometimes construction technique leaves surface texture rough!
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CFD Validation Using Physical ModelingVERIFICATION BEFORE PROGNOSTICATION
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Wind Effects on
Hemispherical Domes
Inflated domes requireinternal pressuresexceeding external
pressures to avoidbuckling.
Internal pressures mustnot be too large or
excessive membrane ortensile forces occur, andmembrane tears.
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Wind-tunnel Study ofInflated Domes
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Newman, Ganguli andShrivastava (1984) studiedpressure distributions onthree inflatable domes in a
boundary layer. H/D = 0.5, 0.37 & 0.25,
H/=0.12-0.13, U=7.5m/s, Re=UD/=226,000
FEM calculations showbuckling occurs on plane ofsymmetry and upwind whenthe internal inflationpressures < 0.7-0.44 of thedynamic pressure at thedome top.
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CSU WEFL Wind Tunnel Experiment
PressureScanner
PressureTransducer
CSU WEFL Industrial Aerodynamics Wind Tunnel
PC-NTComputer
PostprocessSoftware
Hot FilmAnemometer
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Wind-Tunnel Initial Conditions
Grid: 86,000 cells
Velocity Contours:
Umax = 15 m/s
Z = 1m
Z = 0.8 m
ASCE 7-98C
Windtunnel
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Grid Systems: One and Two Domes
18,000 Cells 33,000 Cells 16,400 Cells
43,000 Cells
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Hemisphere Grids
Boundary layer & Hex Grid Boundary layer & Tet Grid
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Velocity & Turbulence Profiles:Single Dome Comparisons
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Single Dome Comparisons:Pressure Profiles
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Single Dome Comparisons:Reynolds Number Variation
Reynolds Number =(U H/) = 185,000
Reynolds Number =(U H/) =
1,440,000
Conclusion: Nosignificant difference
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Single Dome Comparisons:Turbulence Models
Standard kappa-epsilon model
(2 equations) Reynolds stress
model (7 equations)
Spalart Allmaras
model (1 equation) Conclusion: No
significant difference
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Single Dome Comparisons:Pressure Profiles
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Single Dome Comparisons:Smooth vs Rough
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Double Dome ComparisonsApproach wind at 90o
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Double Dome ComparisonsApproach wind at 90o
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Surface Pressures:Angles 0o, 45o & 90o
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Pressure Coefficient Contours:
Experimental vs Numerical:Approach wind at 0o
Cp Contours: numerical
Cp Contours:experimental
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Double Dome ComparisonsApproach wind at 0o
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Double Dome ComparisonsApproach wind at 45o
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Pressure Coefficient Contours:Experimental vs Numerical:
Approach wind at 90o
Cp Contours: numerical
Cp Contours:experimental
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Double Dome ComparisonsApproach wind at 90o
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Conclusions
CFD calculations reproduced mean Cpbehavior over smooth, rough and paired
domes. CFD calculations using k-, RNG, and
Rey turbulence models gave similarresults.
CFD calculations at high and lowReynolds numbers gave similar results.
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WHALE WATCHING
IS NOT AN
EMERGENCY KEEP
DRIVING
GOOD LUCK
Approaching the End
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The End