How to calculate mass flow rate?

[davyjacob]

Hello guys!

Air (compressible fluid) and water (Incompressible fluid) is allowed to flow through a tube without mixing with each other. I need to find the flow rate at the outlet (both air and water flow rate). How this can be done? By what device we can find? Any idea?

thanks & regards,
Davy

 

[racookpe1978]

What class is this for?

 

[LittleInch]

Normally two ways of doing this (two phase flow metering)

Either run it into a separator / knock out drum and then maintain the water level and measure gas flow and water flow separately or use a multiphase meter.

Also if you measure what goes in then what comes out will be the same....

This is very vague and hence I'm afraid gets you a vague answer. Depending on the different quantities, velocity of each fluid and orientation of the pipe, your air and water may mix, become a mist, annular flow (really odd), slug flow, wavy flow...



My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[cvg]

first of all, how do you "not allow it to mix". that would not be a simple task.

 

[racookpe1978]

If the two are separated completely - like a sewage pipe or irrigation ditch with laminar gravity flow ? - then you'd need an air flow detector (propeller ?) in the top, and a separate flow indicator in the bottom. But you need a level detector and pressure gage as well as a velocity detector.

If mixed flow in a confined chamber?