Flow rate of a pipe - calculation

[AnneX]

Homework Statement

It is not an assignment but a problem I came across while studying for a quiz

Relevant Equations

See below, I inserted it, not sure if it applies to this problem though

So, I actually do not know, if the formula given applies to this problem or not, so I wanted to check

 

[gmax137]

That formula looks like it is relating the flow rate to the pressure loss; you don't need that for the given problem. Can you write an equation relating flow rate, velocity, and area? That's all you need to do here.

I think that's what you are doing in the last two lines but you should write out the equation.

 

[Lnewqban]

They are asking for average speed and giving you the volumetric flow rate.

Please, see:
https://www.engineeringtoolbox.com/pipe-velocity-d_1096.html

 

[AnneX]

So, average speed equals volumetric flow rate times area? Just a bit confused, coz it was stated, that I have to find the flow rate

 

[Lnewqban]

The answer choices are in m/s.

 

[gmax137]

So, average speed equals volumetric flow rate times area?

No, if you write this out showing the units (m^3/sec and m^2) you will see it cannot be, but maybe you can figure out the right equation.

 

[Lnewqban]

So, average speed equals volumetric flow rate times area? Just a bit confused, coz it was stated, that I have to find the flow rate

Velocity is directly proportional to the volume per unit of time that flows inside the pipe.
The bigger the cross area of the pipe, the slower the flow.
Be careful with the conversion of units.

 

[AnneX]

So, I guess that is the equation I was looking for?

 

[AnneX]

What is the difference between flow and flow rate?

 

[gmax137]

In US English they are used interchangeably, though I think "flowrate" is more correct. If you are translating from another language be careful (I see how you write your "ones" )

"Volumetric flowrate" is even better. It distinguishes from "mass flowrate" which could be kg/sec, or pounds per hour, or any other MASS/TIME depending on convention for the application.

 

[AnneX]

Thanks, and yeah the one is just a straight line in the U.S. - right? But the fact that I am using the metric system also kind of gives it away, so ;)