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The QuickWave software takes your
AWAC, Aquadopp, Vector, or Aquadopp profiler data
and calculates the wave directional
spectrum.
For AWAC data, the wave spectrum is calculated using the
Maximum Likelihood Method with Surface Tracking (MLM-ST).
The MLM-ST uses Acoustic Surface Tracking (AST) from the AWAC
to estimate the non-directional spectrum (wave height & period)
and uses the three
near-surface velocity cells to calculate the wave directional spectrum. In
addition, the software calculates the peak
wave period, the mean wave period and the
directional spread.
For Aquadopp, Aquadopp Profiler and Vector data,
the wave spectrum is calculated using the
PUV method, meaning that the pressure is
used to estimate the wave height and the two
horizontal velocity components U and V are
used to calculate the wave direction. In
addition, the software calculates the peak
wave period, the mean wave period and the
directional spread.
The QuickWave software has a simple
text-based interface. It reads the data file
you have collected, checks the quality of
the data, and generates a new ASCII file
with the wave parameters. It also generates
a separate file for the wave spectra so you
have the opportunity to study the underlying
physics in more detail. Since there is no
graphical presentation of the results, it
represents Nortek’s simplest solution to
post processing of wave data. The only input
required is the name of the file to be
processed and the distance the instrument
was mounted off the bottom.
View screen image
A demonstration version of the program is
available. This program comes with a
Aquadopp profiler data file and it gives you
an idea of the program output and functions.
Demo Software: QuickWaveDemo.exe
Applications
Instruments used to collect PUV data should be deployed in 20 m of water or less. Because of the strong attenuation that comes into play for short waves, the method is primarily suited for wave situations dominated by swell or storm wave off the coast. The exception is the Vector, which can be mounted in very shallow water, and is suitable for also measuring locally generated wind waves. Read more about the possibilities and the limitations of the PUV method here (TN019)!
Specifications
Input
The following instruments can be used to calculate the wave directional spectrum:
- AWAC data collected in wave mode
- Aquadopp data collected in diagnostic mode (sample restrictions)
- Aquadopp profiler data with data collected in wave mode
- Vector data if collected using burst mode (sample restrictions)
Functionality
The wave parameters output includes the following parameters:
- Hs - significant wave height (m)
- Tm02 -mean zero crossing period (s)
- Tp - peak period (s)
- DirTp - direction at Tp (deg)
- SprTp - spreading at Tp (deg)
- MainDir; main wave direction (deg)
- UI; unidirectivity index H3;
ErrCode - Error Code for bad data
The last parameter, nErrCode, indicates if the data was processed without any errors or the type of error encountered. The errors which are checked for are as follows:
- No pressure signal (out of water)
- Low pressure signal
- Low Doppler signal strength
- White noise test estimates out of bounds
- Estimates out of bound
Output
- ASCII file with all the wave parameters
- ASCII file with the estimated surface spectrum for all times
System requirements
Any PC running Windows 98, XP, NT, 2000.
Additional Resources
Principles of wave directional spectra
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