Multi-sensor Observations of Grid Generated Turbulence

To characterize near-surface turbulence, a series of cross-calibration experiments were conducted in a flume within the Surge-Structure-Atmosphere Interaction (SUSTAIN) laboratory at the University of Miami. Turbulence was generated by pumping water through a heater and a vortex-generating grid (10 cm x 10 cm). Hot-film anemometery, a pulse-coherent acoustic profiler, and shear probes were used to measure along-stream turbulent velocity field downstream of the grid. An Optical Turbulence Sensor (OTS) and an infrared camera were also used to measure the surface and vertical temperature profile. Particle image velocimetry (PIV) was used to map the turbulent flow immediately upstream of the OTS. Both turbulence energy spectra and passive scalar spectra were consistent with previous experiment work and theoretic results. The comparisons between the turbulence measurements made across the different instruments will be discussed.