adcp acoustic doppler current profiler morven muilwijk 2014 university of bergen, bjerknes centre...
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ADCP Acoustic Doppler Current Profiler
Morven Muilwijk2014
University of Bergen, Bjerknes Centre for Climate Research
What is an ADCP?
• Acoustic Doppler Current Profiler
Morven Muilwijk 2014
The Doppler Shift
Morven Muilwijk 2014
The Doppler Shift
Morven Muilwijk 2014
The Doppler Shift
Morven Muilwijk 2014
Speed of sound = frequency × wavelength
The Doppler Shift
Morven Muilwijk 2014
Current profiling and 3D velocity measurements
4 Measurements at once:
1. Speed and direction
2. Bottom tracking
3. Height or range
4. Distribution of material (intensity)
Morven Muilwijk 2014
Different types, different purposes
Morven Muilwijk 2014
Different types, different purposes
Morven Muilwijk 2014
Applications of the ADCP
• Oceanography• Vessel Traffic Safety in the Port & Harbor• Tidal currents observations • Efficient Seismic Survey Operations
Morven Muilwijk 2014
Applications of the ADCP
Morven Muilwijk 2014
•Oil industry•ADCPs for renewable energy projects
New York power plant
Morven Muilwijk 2014
Different types of platforms
Morven Muilwijk 2014
Examples of studies
• Measuring tidal currents in a sound
Morven Muilwijk 2014
Examples of studies
• Measuring tidal currents in a sound
Morven Muilwijk 2014
Advantages
• Easy to use and to make profiles • No moving parts• Small scales • Absolute speed of water• Measures columns up to 1000m
Morven Muilwijk 2014
Disadvantages
• Barnacles and algea • Clear waters • Compromise between distance or precision • Bubbles in turbulent water• Battery power with
frequent pings
Morven Muilwijk 2014
Good to know when working with ADCP’s
• Backscatter • Ping • Main Lobe• Blank zone• Ambiguity
Morven Muilwijk 2014
ADCP Acoustic Doppler Current Profiler
Morven Muilwijk2014
University of Bergen, Bjerknes Centre for Climate Research