Rouse number

The Rouse number (P or Z) is a non-dimensional number in fluid dynamics which is used to define a concentration profile of suspended sediment and which also determines how sediment will be transported in a flowing fluid. It is a ratio between the sediment fall velocity ${\displaystyle w_{s}}$ and the upwards velocity on the grain as a product of the von Kármán constant ${\displaystyle \kappa }$ and the shear velocity ${\displaystyle u_{*}}$.

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