Calculating Velocity in a Pipe: Flow Rate 0.01, Diameter 90mm

  • Thread starter Thread starter fowler2k
  • Start date Start date
  • Tags Tags
    Pipe Velocity
AI Thread Summary
To find the velocity within a pipe, the correct formula is V = Q/A, where Q is the flow rate and A is the cross-sectional area. The area A can be calculated using A = π/4 x D^2, with D being the diameter in meters. For a flow rate of 0.01 m³/s and a diameter of 90 mm (0.09 m), the area should be calculated in square meters, not square millimeters. The correct area calculation results in A = 0.00636 m², leading to a velocity of approximately 1.57 m/s. It's crucial to ensure all units are consistent to avoid errors in calculations.
fowler2k
Messages
4
Reaction score
0
I need to find the velocity within a pipe , I know the flow rate and diameter

Flow rate =0.01
Diameter =90mm

Am I correct in thinking to use V =Q/A

Where A is found using A=pi/4 x D^2

Using this I got A =0.0064m but somehow this does not seem quite right to me

Can anybody please tell me where I am going wrong please

Thanks
 
Engineering news on Phys.org
Please include units for all quantities. How else can we tell what these numbers mean?
 
0.01m3 s-1
 
fowler2k said:
I need to find the velocity within a pipe , I know the flow rate and diameter

Flow rate =0.01
Diameter =90mm

Am I correct in thinking to use V =Q/A

Where A is found using A=pi/4 x D^2

Using this I got A =0.0064m but somehow this does not seem quite right to me

Yes, it's not quite right. Your answer is a length...you want an area.
 
Ah so it should be m^2 ?
 
What are the units for your flow rate?

And also, Your equation for area includes the term D^2 which implies the diameter is being squared, so your answer for area should have the units mm^2.
 
Back
Top