- #1
MonkeyMouse
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Homework Statement
Helium at 20°C passes through a pipe with an initial diameter of .3 meters decreasing to .25 meters. The helium flows at .30 kg/s and an initial pressure of 200 kpa. Find the difference in pressure ΔP across the decreasing section. Assume incompressible and inviscid flow.
From known values of helium at 20°C: Density= 0.166 kg/m3, Specific weight= 1.63 N/m3,
Homework Equations
Bernoulli eq: (p1/[itex]\gamma[/itex])+(V12/2g)+Z1=(p2/[itex]\gamma[/itex])+(V22/2g)+Z2
V=Q/A
The Attempt at a Solution
Not a free jet situation.
Z1 and Z2 = 0 due to no elevation change
A1=([itex]\pi[/itex].3m2)/4=.0706m2
A2=([itex]\pi[/itex].25m2)/4=.0491m2
My hang up is when I get to this point, Q=.30 Kg/s and I am unsure how to convert this to m3/s in order to find V1 and V2 in terms of m/s? Also once I have this I am unsure of the unit conversions I would need to return P2 in kpa in order to find the pressure difference?