Velocity point-measurements

Welcome to the velocity point-measurements subgroup!

This subgroup addresses best practices in obtaining turbulent kinetic energy dissipation rate estimates from time series of velocities measured at a point in space. These temporal measurements are converted into spectral observations in the wavenumber (space) domain before being fitted with a model spectrum to obtain turbulent kinetic energy dissipation.

Scope

The subgroup will provide recommendations on all processing stages for obtaining [math]\displaystyle{ \varepsilon }[/math]:

1. data processing of raw measurements
2. segmenting datasets and decomposing the velocities into the mean, turbulence and surface waves component.
3. spectral computations and identifying the appropriate inertial subrange model (e.g., surface wave considerations)
4. estimating [math]\displaystyle{ \varepsilon }[/math] and associated quality control measures

These four processing levels coincide with the hierarchal format of the ATOMIX NetCDF velocimeters format for the benchmark datasets. These benchmarks are intended to be a resource that the community can use to evaluate routines in any programming language. Our recommendations are designed for measurements collected by any manufacturer, provided the data quality is sufficient for resolving the turbulence subrange of the velocity spectra.

We will be providing benchmarks for velocity measurements both impacted and unaffected by surface waves. We will not be giving benchmark datasets for moored platforms at this time. However, we will include appropriate references to existing literature.