Fluid Mechanis - Pipe Flow Velocity

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360modina
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Homework Statement


I'm looking for a formula that has velocity at a certain point in a pipe. I only have velocity and pipe diameter.

The problem goes something like:

A Tube with a 0.075 meter diameter has four drains equally spaced apart
with a cap at the far end. Each of the four drain opening has a flow of
15 L/s.

I need to find the average Vs in the tube between each of the drains, I marked them as 1, 2, and 3. If the flow is laminar, what are the max velocities at 1, 2, and 3? List assumptions needed for solving.

Schematic of a horizontal pipe with an inlet arrow and label 75 mm diam. at the left end, capped at the right end, with four side drains each labelled 15 l/s and sections numbered 1, 2 and 3 between them.



Homework Equations


I'm still missing a relevant formula...


The Attempt at a Solution


To start of I think that three boundary systems would need to be used:
System 1:
Inlet
Drain 1
Location 1

System 2:
Drain 2
Location 2

System 3:
Drain 3
Location 3
Drain 4
 
I worked on the problem a bit more:

I found the pipe area

A= 0.785 * Diameter2
=4415.625mm2

and Q or liquid flow rate = Rho * V * Area

so in order for the first velocity at the drain to be 15l/s, the Q must be at least 66.27 l/s

I'm still pretty stuck though and not sure if I'm going in the right direction
 
to find the entrance flow rate you have to do continuity, so pVa=4(pVa)