Experimental investigations on complex vortex flows using advanced flow diagnostic techniques

Visualization of flow structures around a gable-roofed building model in tornado-like winds

“…Due to the strong swirling motion of the tornado-like vortex, the wake vortex structures were found to become highly turbulent and unsymmetrical inclining towards the vortex center. The corresponding wind load measurements (results not shown at here) also confirmed that the tornado-induced wind loads would be about three times higher compared to those in straight-line winds (Yang, 2009). Based on the PIV measurements at different horizontal and vertical planes, 3-D flow structures around the test model were reconstructed.…”

“…In addition to measuring the wind loads (both forces and moments) acting on the test model using a high-sensitivity load cell, a digital PIV system was used in the present study to conduct detailed flow field measurements to quantify the unsteady vortex and turbulent flow structures around the gable-roofed building model in tornado-like winds. Further information about the experimental setup, digital PIV system and image processing procedures, temporal and spatial resolution of the PIV measurements and the estimation of the measurement uncertainty is available in Yang (2009).…”

Visualization of the tip vortices in a wind turbine wake

“…In addition to conducting ''free-run'' PIV measurements to determine the ensemble-averaged statistics of the flow quantities such as mean velocity, turbulence intensity, Reynolds stress, and turbulence kinetic energy, phased-locked PIV measurements were also conducted in order to elucidate more details about the time evolution of the helical tip vortices in relation to the position of the rotating turbine blades. Further information about the experimental setup, shapes of the turbine blades, tower and nacelle designs, digital PIV system and image processing procedures, temporal and spatial resolution of the PIV measurements and the estimation of the measurement uncertainty is available in Yang (2009).…”

An Experimental Investigation on the Trailing Edge Cooling of Turbine Blades by using PIV and PSP Techniques

“…4, where the measurement data was fitted to a polynomial curve. Further information about the experimental setup and PSP calibration procedure is available at reference [19].…”

“…5, which is difficult to be obtained by the measurements of those heat transfer experiments due to the effects of heat conduction. In order to gain more insight into the underlying physics pertinent to the trailing edge cooling, Yang [19] conducted detailed PIV measurements to characterize the dynamic mixing between the mainstream flow and coolant stream over the trailing edge model used in the present study. While further detailed information and discussions about the PIV measurements are available at Yang [19], some typical PIV measurement results were shown in the present study to facilitate the understanding of the characteristics of trailing edge cooling revealed from the PSP measurements.…”