Effects of very-large roughness in turbulent channel flow
نویسندگان
چکیده
The streamwise velocity statistics in fully-developed rough-wall channel flow have been investigated over gritand mesh-type surface topologies. The flow was demonstrated to be fully-developed and two-dimensional up to the fourth moment of velocity. Though the flow over both surface types appear to exhibit a limited logarithmic region, the regions of inner and outer scaling over the mesh surface fail to overlap. The influence of the spanwise periodicity of the mesh upon the outer scaling is discussed.
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