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von Karman Institute activities for

SBO Project CarParks

Jeroen van Beeckvon Karman InstituteSint-Genesius-Rodewww.vki.ac.beMeeting Place: WFRGentDate: 6-2-2009, 11:00 - 17:00

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VKI ACTIVITIES

Education programs for graduate and undergraduate students.Organization of 10 Lecture Series / year.Consultant activities for industry.

von Karman Institute for Fluid Dynamics

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VKI DEPARTMENTS

Aerospace and Aeronautics DepartmentEnvironmental and Applied Fluid Dynamics Department Turbomachinery and Propulsion Department

Wind speed-up around new Belgian Antarctic building

Pressure tap model of new Belgian Antarctic building

CFD simulations Laboratory tests

von Karman Institute for Fluid Dynamics

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Hypersonic Wind Tunnel (Mach 14, 2500K)

Plasmatron (1.2 MW, Mach 2, 10000K)

Subsonic Wind Tunnel (3m, 60m/s)

High Pressure Turbine Stage (1 MW)

VKI LARGE SCALE FACILITIESvon Karman Institute for Fluid Dynamics

SBO Project CarParks 6/2/2009 WRFGent

– AERONAUTICS & AEROSPACE• Hypersonic Aero-thermodynamics• Mars Reentry Vehicles, Arianne Launchers, Man-in-space

– ENVIRONMENTAL & APPLIED FLUID DYNAMICS • Wind Loading, Wind Comfort, Pollutant Dispersion, Wind Energy• Multiphase Flows with Smoke, Bubbles, Snow & heat transfer• Aero-acoustics• Biological Flows

– TURBOMACHINERY & PROPULSION • Unsteady Flows in Turbines, Compressors and Pumps• Film Cooling and Optimization of Turbine Blades• Micro-turbines

von Karman Institute for Fluid Dynamics

Sint-Genesius-Rodewww.vki.ac.be

Scotch Gambit of Panamarenko in front of VKI on the occasion of its 50th Anniversary 1956-2006

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VKI activities for CarParks

• Characterization of Sprinkler systems

• Small-scale wind tunnel tests

• Full-scale field tests

• Development of Large-Scale PIV for field tests

von Karman Institute for Fluid Dynamics

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Sprinkler Characterization Phase Doppler Anemometry @ VKI Water Spray Facility WS-1

von Karman Institute for Fluid Dynamics

droplet size and velocity distributions & mass flow rates

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Small-scale wind tunnel tests

• Car park building, scale +/-1:20 -> 1.5m x 1.5m x 0.16m, CFD validation

• Fire simulated by Helium gas source

• Quantities to be monitored:– air velocity field using standard PIV;– Helium concentration by hot wire aspiration probes.

• The parameters to be studied:– Helium flow rate;– External wind velocity;– Wind direction;– Jet fan speed.

von Karman Institute for Fluid Dynamics

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Umax= 60 m/s

VKI L-1B WIND TUNNEL, 20m x 3m x 2m von Karman Institute for Fluid Dynamics

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Field tests

Equipment:– thermocouples for temperature measurements;– video equipment for registration of smoke movement -> LS PIV;– hot-spheres for gas velocity;– For the smoke density database, the installed smoke detectors will

give valuable information for the database. LS PIV could possibly yield quantitative information on smoke density as well.

Parameters:– Obstacles for smoke movement such as downstands, columns,

smoke curtains;– Ventilation flow rate of the axial jet and induction fans;– hot flow tests with a pool fire; influence of different types of smoke

extraction devices.

von Karman Institute for Fluid Dynamics

SBO Project CarParks 6/2/2009 WRFGent

2D or 3D velocity field of an instantaneous spatial flow structure

PARTICLE IMAGE VELOCIMETRY (PIV)

CAMERA records particle image field on time t1 and t2, e.g. when laser pulses

V=Δx / t2-t1(1 vector / interrogation cell)

von Karman Institute for Fluid Dynamics

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ANNULAR VORTICES IN A JETvon Karman Institute for Fluid Dynamics

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ANNULAR VORTICES IN A JETvon Karman Institute for Fluid Dynamics

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time t2time t1

Image Windowing

PIV IMAGE PROCESSING

Interrogation window

SearchWindow

von Karman Institute for Fluid Dynamics

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to+Δtto

1 4 7

10 13 16 19 22 25 28 31

S 1

S 7

S 1 3

S 1 9

S 2 5S 3 1

rδ

( )( ) ( )

( ) ( )∑ ∑ ∑ ∑

∑ ∑

−= −= −= −=

−= −=

⋅⋅

−−⋅

=N

Ni

N

Nj

N

Ni

N

Nj

22

N

Ni

N

Nj

j,iSj,iI

nj,miSj,iI

n,mR

PIV IMAGE PROCESSING

V=δ/ΔtWindow displacement δ via maximum in cross-correlation function:

von Karman Institute for Fluid Dynamics

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ANNULAR VORTICES IN A JETvon Karman Institute for Fluid Dynamics

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ANNULAR VORTICES IN A JETvon Karman Institute for Fluid Dynamics

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INSTANTANEOUS VELOCITY FIELD

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VORTICITY FIELD

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VORTICITY + VELOCITY

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Large Scale PIV

Von Karman vortices downstream a cylinder 16 cm diameter - Free stream velocity 0.23 m/s

Field of View: 1m X 1.3 mPIV is often applied to heat-induced flows because it is a non-intrusive technique that is capable of measuring very low velocities at any temperature conditions.

The current limitation is the maximum size of the flow-field of 30 cm x 30 cm because of the loss of resolution of tracers.

Large Scale PIV (LS PIV) has been developed to overcome these limitations: A pattern recognition technique is applied to images of flow structures instead to images of tracer dots

von Karman Institute for Fluid Dynamics

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VKI personnel involved in CarParks

Jeroen van Beeck, Associate Professor (NL)

Istvan Horvath, Ph.D candidate (H)

Rosaria Vetrano, Research Engineer (It)

Philippe Planquart, Research Engineer (B)

Guillaume Diquas, Industrial Engineer (B)

VKI Technicians for wind tunnel model construction and help in field tests

von Karman Institute for Fluid Dynamics