Measurement of Turbulence with Acoustic Doppler Current Profilers -- Sources of Error and Laboratory Results

摘要

Acoustic Doppler current profilers (ADCPs) provide a promising method forrnmeasuring surface-water turbulence because they can provide data from a large spatialrnrange in a relatively short time with relative ease. Some potential sources of errors inrnturbulence measurements made with ADCPs include inaccuracy of Doppler-shiftrnmeasurements, poor temporal and spatial measurement resolution, and inaccuracy ofrnmulti-dimensional velocities resolved from one-dimensional velocities measured atrnseparate locations. Results from laboratory measurements of mean velocity andrnturbulence statistics made with two pulse-coherent ADCPs in 0.87 meters of water arernused to illustrate several of inherent sources of error in ADCP turbulence measurements.rnResults show that processing algorithms and beam configurations have important effectsrnon turbulence measurements. ADCPs can provide reasonable estimates of manyrnturbulence parameters; however, the accuracy of turbulence measurements made withrncommercially available ADCPs is often poor in comparison to standard measurementrntechniques.