Flow Velocity- Guranteed to be Laminar

AI Thread Summary
To determine the maximum average flow velocity for laminar flow in a pipe with a diameter of 50.0 mm, the Reynolds number must be calculated using the formula Re = (pvd)/n. For water at 20°C, with a density (p) of 998 kg/m^3 and a dynamic viscosity (n) of 1.0 x 10^-3 Pa.s, laminar flow is guaranteed when the Reynolds number is less than 2000. The discussion emphasizes that the missing component for the calculation is selecting an appropriate Reynolds number that ensures laminar flow. Participants suggest using the established threshold values for Reynolds numbers to find the maximum flow velocity. Understanding these parameters is crucial for solving the problem effectively.
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Homework Statement



Q) Water (p = 998 kg/m^3
, n = 1.0*10^-3 Pa.s at 20C) at 20C flows through a pipe of
diameter 50.0 mm. What is the maximum average flow velocity if the flow is
guaranteed to be laminar? Give your answer in mm/s.

Homework Equations



Reynolds number=(pvd)/n

The Attempt at a Solution


I am absolutely stumped on this last question for my assignment, I have no idea what to or how to calculate the flow from just these given constants.
 
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You're given everything you need for the equation, except for the "soft" values Reynolds numbers that are a result of laminar flow. Most agree on the following:

for circular pipe flow only

laminar: Re < 2000
transitional: 2000 < Re < 4000
turbulent: Re > 4000

So, pick a Re that you think will "guarantee" laminar flow, plug n chug.

Hope I didn't just give it away too easily, but the values of Re were the only thing that you were missing.
 

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