How to convert pressure (Bar) to flow rate (L/min)?

AI Thread Summary
To calculate the pressure needed for a flow rate of 3 L/min of Argon gas, it's essential to consider the length of the pipe, as pressure drop varies with pipe length. The internal radius of the pipe is 2.3mm, and the pressure can range from 0 to 5 bar. Understanding the pressure drop is crucial, as it is influenced by multiple variables, including the compressibility of the gas, especially when pressure changes significantly. The methodology for this calculation is detailed in Chapter 7 of "Transport Phenomena" by Bird, Stewart, and Lightfoot. Accurate calculations will require considering the square of the absolute pressure due to the compressibility effects.
avishay
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hii,

I'm try to calculate the pressure (in bar) needed for a certain flow rate 3 L/min of Argon gas given the following setup:
- I have a tank of Argon gas and the line pressure can be between 0 bar to 5 bar.
- The gas will flow out to the open air in the end.
- My pipe has an internal radius of 2.3mm.

I will be very happy if someone can also explain to me the process of getting to the answer...

Thanks for the help :)
 
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Hello avishay, ##\qquad## :welcome: ##\qquad## !

Your problem statement isn't complete: for a short pipe the pressure drop is less than for a long pipe.

With the expressions in the link you can calculate ##\Delta p## for your pipe length.
 
I didnt really understod how to calculate this prameter, I'm not really sure why i need this...
any help?
:)
 
avishay said:
I didnt really understod how to calculate this prameter, I'm not really sure why i need this...
Pressure drop is a function of length or rather is given per unit length.
 
avishay said:
calculate this parameter
It's not really a parameter: according to the link it's a result of a bunch of variables.

What have you calculated yourself so far ?
 
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The methodology for solving a problem like this is presented in Chapter 7 of Transport Phenomena by Bird, Stewart, and Lightfoot. But, please note that, in a case like this where the gas pressure change can be as large as a factor of 6, you will need to take into account the compressibility of the gas, and, as such, will probably be working in terms of the square of the absolute pressure (rather than the absolute- or gauge pressure to the 1st power).
 
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