Homework Help: Flow Velocity- Guranteed to be Laminar

1. Oct 10, 2012

flash_659

1. The problem statement, all variables and given/known data

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

2. Relevant equations

Reynolds number=(pvd)/n

3. 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.

2. Oct 10, 2012

Spinnor

Last edited by a moderator: May 6, 2017
3. Oct 10, 2012

2h2o

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.