On spatial resolution issues related to time-averaged quantities using hot-wire anemometry

Authors: Örlü, R., Alfredsson, P.H.
Document Type: Article
Pubstate: Published
Journal: Exp. Fluids
Volume: 49   101-110
Year: 2010


The effect of spatial resolution on streamwise velocity measurements with single hot-wires is targeted in the present study, where efforts have been made to distinguish between spatial resolution and Reynolds number effects. The basis for measurements to accurately determine the mean velocity and higher order moments is that the probability density distribution is measured correctly. It is well known that the turbulence intensity is increasingly attenuated with increasing wire length. Here, it is also shown (probably for the first time) that besides the probability density distribution and hence the higher order moments, even the mean velocity is affected, albeit to subtle extent, but with important consequences in studies of concurrent wall-bounded turbulence.