the proper and quantitative recognition of the scale of turbulence in regard to issues such as sediment transport is of major importance. different experimental techniques can be used to determining the scale of turbulence, but the accuracy of these techniques is open to question. in this paper, after a review of the taylor method, the restrictions and advantages of velocity measurement techniq...

the aim of the present study was to investigate the influence of nozzle configurations on spray drift and explain the influences using several atomization characteristics (length of spray sheet, spray angle, velocity distribution of flow field, fluctuation of velocity, and droplet size). nozzles manufactured by one company (lechler gmbh, germany) were tested by spraying local tap water in a win...

The existing particle image velocimetry (PIV) do not consider the curvature effect of non-straight trajectory, because it seems to be impossible obtain information from a pair images. As result, computed vector underestimates real velocity due straight-line approximation, that further causes systematic error for PIV instrument. In this work, curved trajectory between two recordings is firstly e...

Background: Optical distortions can significantly deteriorate the measurement accuracy in particle image velocimetry systems. Such distortions can occur at fluctuating phase boundaries during flow measurement and result from the accompanied refractive index changes. The usage of a wavefront sensor can be hindered by disturbing light reflexes or scattering. Methods: A combination of sharpness me...

Autocorrelation-Based Estimate of Particle Image Density in Particle Image Velocimetry

Particle image velocimetry and a 3D hard sphere discrete particle model were applied to determine particle velocity profiles in the plane around a spout in a spoutfluid bed for various initial bed heights, spout and background fluidization velocities. Comparison between experimental and numerical results revealed that the particle velocities are underestimated by particle image velocimetry, whi...