When using Bernoulli's equation and calculating Reynold's number which one do we use?
You mean for the vevlocity ? Some context, please !
Yes. Do we use the bulk velocity or center line velocity when using Bernoulli's equation and calculating Reynold's number?
Bernoulli is for inviscid flow, so I would use the bulk velocity and exercise care when a low Re number comes out that indicates laminar flow !
See the caveat here and keep an eye on the laminar flow result (Poiseuille)
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