Thank you Mohamed Hamdaoui. In your attachment the ranges given for Reynolds number are for air only. These are not for water.
Subhasish: By definition Reynolds Number is expressed as Re = (flow velocity x hydraulic diameter)/kinematic viscosity of fluid. If water is still then Reynolds Number is exactly zero. Which means flow is Laminar.
There are three types of flow (e.g. Laminar Flow, Transient Flow & Turbulent Flow) characterized by Reynolds Number. Generally, Reynolds Number < 2100 is Laminar Flow, Reynolds Number = 2100 ~ 4000 is Turbulent Flow.
Based on several environmental conditions (e.g. Fluid Temperature, Pressure, composition) and hydraulic properties (e.g. fluid velocity, hydraulic diameter), Reynolds Number shall varies. During horizontal jet propulsion in water, based on environmental conditions and hydraulic properties, you may expect turbulent flow if x-z velocity profile is almost uniform through out the flow depth. If x-z velocity profile is parabolic and velocity at channel bed is very small then you may expect different Reynolds Number at different flow depths. Laminar Flow may occur at and near channel bed.
In case of Open Channel Flow, the previous discussions are applicable.
I wanted to know the Reynolds number of the jet, not about the text book theories on Reynolds number of still water.
Also after the horizontal jet propulsion the velocity of water will be zero. Therefore the flow will not be laminar.
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