bergische universität wuppertal - hd high speed …...bergische university of wuppertal fon: +49...
TRANSCRIPT
11. March 2010
A. Derichs, F. Hamacher, T. Motz, J. Müller, L. Hoppenheit
Dr. M. Oertel, Prof. Dr. A. Schlenkhoff
Hydraulic Engineering Section Civil Engineering Departement
Bergische University of Wuppertal GERMANY
HD High Speed Camera to investigate breaking waves
Slide 2 Breaking Waves 11. March 2010
Contents
• Introduction
• Lab / test set-up
• Test results / evaluation
• Summary
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
Slide 3 Breaking Waves 11. March 2010
Introduction
The ambition:
• Generating a breaking wave in the wave flume
• Capturing the breaking wave with a highspeed camera
• Analysis of the intakes
• Visualisation of particle movement under the breaking wave (velocities and direction)
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
Slide 4 Breaking Waves 11. March 2010
The Laboratory
• Wave channel
• 24 m length, 0.3 m width, 0.5 m heigth
• 0.3 m waterlevel
• wave generating paddle
• wave generation by own developed software
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
Slide 5 Breaking Waves 11. March 2010
The Laboratory
Creating a breaking wave
• GUI wave flume
• superposition of particular waves
• forming a plunging breaker
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
Slide 6 Breaking Waves 11. March 2010
Test setup
• High speed camera
• use of tracers
• similar density to water
• polyamide
• diameter < 1mm
• sheet of blackboard
• spotlights
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
Slide 7 Breaking Waves 11. March 2010
HD High Speed Camera
Imaging Solution Motionscope M3
• Resolution 1280 x 1024
1,3 Megapixel
• Pixelsize 12 x 12 µm
• Recordingfrequency max: 1280 x 1024 @ 517 fps
1280 x 16 @ 33000 fps
used: 1280 x 512 @ 1000 fps
• Output: video (.avi, .mpeg, .mp4)
single picture ( .jpg, .tiff, .bmp, .png, …)
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
Slide 8 Breaking Waves 11. March 2010
Test run
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
Slide 9 Breaking Waves 11. March 2010
PIV - Particle Image Velocimetry - MatPIV (Sveen)
1) define a coordinate system (6 coordinates )
internal x- axis 0.3 m internal y- axis 0.2 m
2) blank out non relevant areas 3) start MatPIV analysis 4) filter & interpolate results 5) visualisation of results
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
Slide 10 Breaking Waves 11. March 2010
PIV - Particle Image Velocimetry Source: LaVision
• method of velocity measurement
• tracers „mixed“ into water
• two frames
• measurement of distance during a certain time-increment
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
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Slide 11 Breaking Waves 11. March 2010
Velocity Magnitude:
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
Slide 12 Breaking Waves 11. March 2010
Velocity Vectors:
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
Slide 13 Breaking Waves 11. March 2010
Streamlines:
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
Slide 14 Breaking Waves 11. March 2010
Vorticity:
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
Slide 15 Breaking Waves 11. March 2010
Thank you for your attention!
Hydraulic Engineering Section
Bergische University of Wuppertal
Fon: +49 202 439 4195
Fax: +49 202 439 4196
Summary
Contents
Introduction
The Laboratory
Test setup
HD High Speed Camera
Test run
PIV - Particle Image
Velocimetry
Summary
• generated a breaking wave • captured it with a high speed camera
• analysed intakes using MatPIV
• Visualisation of particle movement