- #1
musicmar
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Homework Statement
Given: water at 20°C flows through a 3cmID smooth brass tube at 0.002 m^3/s.
Homework Equations
V=Q/A
f=64/Re
Re=VD/(nu)
The Attempt at a Solution
V=Q/A=(0.002 m^3/s)/((∏/4)*(0.03 m)^2) = 2.829 m/s
Re=VD/(nu)
= (2.829 m/s)*(0.03 m)/(1x10^-6 m^2/s)=84882.64
f=64/Re=0.0075
I know this is wrong for two reasons:
1. The numeric answer is in the back of the book: 0.0185
2. Looking at the Moody Diagram: there is no f value on the chart below 0.008.
Any help in finding my mistake would be appreciated.
Thank you.