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PIV applications. Presentation of a select range of PIV applications. Historic review of measurements then and now. Aerospace. Aircraft model aerodynamics Wing design (drag & lift) Trailing vortices Helicopter rotor design Super sonic flows Gas turbine fuel injection & cooling
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PIV applications • Presentation of a select range of PIV applications. • Historic review of measurements then and now.
Aerospace • Aircraft model aerodynamics • Wing design (drag & lift) • Trailing vortices • Helicopter rotor design • Super sonic flows • Gas turbine fuel injection & cooling • Flight cabin ventilation • Validation of CFD models # 33356
Automotive • Car body aerodynamics • Air flows in passenger compartments • Engine compartment flows • Engine combustion
Bio-medical and bio-technology • Artificial hearts • Hart-valve function • Blood flows • Medicine inhalers • Micro fluidics Flow in biological valve, Prof. Roberto Zenit UNAM, Mexico City
Combustion Diagnostics • Fuel injection • Air/fuel mixing • Combustion efficiency • Cooling efficiency • Rocket engineering • Flame research
Earth science & environmental protection • Sedimentation & particle transport • Wave dynamics • Mass transport
Fundamental fluid dynamics research • Turbulence research • Boundary layers • Fluid-structure interactions • Vortex evolution • Heat transfer studies • Super sonic flows • CFD code validation
Hydraulics & hydrodynamics • Ship hull design (hydrodynamics) • Propulsion efficiency • Pipe & channel flows • Flows in pumps • Cavitation prevention (propellers) • Cooling performance
Mixing processes • Research in mixing processes • Flow in industrial mixers • Micro mixers
Process and chemical engineering • Cyclone separators • Heat exchangers • Liquid metal flows (moulds)
Ø30 air jet stimulated by a loud speaker Velocity: ~2.7 m/s Lens: 60mm/#F2.8 S=500mm(Distance between light sheet and lens) 2-3µm oil droplet seeding Field of view:82x103 mm at 1024x1280 pixel Stimulated air jet Fan Grid Jet Loud speaker
Jet flow without stimulation • RMS of the v- velocity component Strongreflection • Vorticity based on 250 Hz PIV
RMS v - flow with45 Hz stimulation RMS V - velocity component • RMS v - flow without stimulation
PIV testing at HSVA Towing tank, Germany Camera Laser PIV system Rudder
HSVA Towing tank measurementTracking the vortex from a rudder
PIV under a microscope Pump Waste Outlet Inlet Microfluidic device Flow + Tracing Particles Lamp Microscope Lens, High NA Optics for lamp / fiber l = 532 nm Filter cube Epi-fluorescent Prism Optical fiber l = 560 nm Ocular Beam splitter Relay lens Max ~5 mJ 12 bit Interline Cooled CCD Camera Nd: YAG Laser
Top View 300 mm z x MeasurementArea Side View 30 mm y x Micro channel Experiments
Micro channel Flow (x - z plane) Courtesy: Meinhart et. Al.
Results at X63 measurement Measurement area
Results at X63 measurement • Magnification X63 (X0.5) = X31.5 • Time between laser pulses 200 µs • Measurement volume 14 x 14 x 8 µm • Vectors spaced 3.4 µm
Shadow Sizing Spray analysis Spatial distribution, cumulative histogram and table for data analysis
Flow-Structure interaction • Flow-Structure solid interaction has been research topic for many years. • Areas of application include: • Aero-elasticity • Bridge design • Building design • Micro air vehicle • Measurement of deformation of and flow behind a flexible winglet. • Flow Measured with TR-PIV • Deformation measured with Digital Image Correlation (DIC) • DIC is a optical technique for Time Resolved (TR-DIC) measurement of 3-D deformation and strain
Flexible wing and it’s influence on flow • Optical measurements of real time Deformation of a Flexible Wing and the associated Flow behind a flexible wing. • The wing has one spare and 4 ribs over which is latex membrane is mounted with adhesive (5.7x3) • Curtsey Mr. Ryan Wallace and Prof. Mark Glauser of Syracuse University
Wing layout and area of investigation Flow field measured by TR-PIV Temporal resolution on TR-DIC and TR-PIV measurements: 1 ms (1kHz) Image of full wing, placed in wind tunnel. Flow 14 m/s angle of attack 4 deg
Point spectral information • Z-displacement spectral in formation from a point
TR-PIV Flow measurements behind wing Flow field behind wing and associated spectrum
Flow measurements then and now • Today we take many things for granted • How have we advanced? • Let’s have a quick review
PIV underwater measurements Maritime research, Propellers in towing tanks 1981 LDA underwater measurements
Airborne studies Airborne LDA measurements 1977 Hotwire in-flight measurements at high altitude and speed Combustion in Micro-gravity with a PIV system onboard
x/b=6.8 0.2 nm x/b=30.0 0.9 nm x/b=63.0 2.0 nm K. & C. Huenecke, Airbus Wingtip vortices, then and now Understanding tip vortices in details with PIV measurements in water 1962 CTA measurements in open air, waiting for the fly-by of the aircraft
Flow Discharge Vectoring using a Miniature Fluidic Actuator mapped with PIV On the way to micro applications 1965 CTA in a “microfluidic” bi-stable fluid amplifier
30 µm deep wall 100 µm wide Microscopic PIV in a 30 x 100 µm wide channel with real human blood When it gets bloody ! 1970 CTA built into a hypodermic needle, used in patients to verify results after operation
LIF measurement in an engine at different crank angles Thermodynamics in combustion 1956 The PV indicator revolutionized combustion understanding. Now, the thermodynamic work was online ! Modern day developments requires much more detail and advanced imaging Result: PV diagram for all crank angles
We can see it - quantification of bubbles with advanced image processing 1967 Investigation of a hot film and bubble interaction Quantification of bubbles with shadow sizing techniques
1971: 5 mWatt laser 2001: 50 Watt laser & more information Jet flow still the same 30 years later ? 1971 First commercial LDAinvestigated by F. Durst and J. Whitelaw 2001 First commercial Time Resolved PIV system based on fast powerful Nd:Yag lasers