Calculating airflow with pressure and diameter?

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enanthate
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Hi.

Is there any way to calculate airflow out of a tube (into atmosphere) with only the pressure and cross sectional area of the tube?
 
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enanthate said:
Hi.

Is there any way to calculate airflow out of a tube (into atmosphere) with only the pressure and cross sectional area of the tube?
Are you talking about the upstream pressure? If so, you also need to know the length of the tube and the temperature (which determines the density and viscosity).
 
Chestermiller said:
Are you talking about the upstream pressure? If so, you also need to know the length of the tube and the temperature (which determines the density and viscosity).

Downstream.. Exit to atmosphere
 
enanthate said:
Hi.

Is there any way to calculate airflow out of a tube (into atmosphere) with only the pressure and cross sectional area of the tube?
Companies that make spray nozzles have calculators that will give you the flow rate given the pressure in the pipe leading to the nozzle (eg the upstream pressure) but they assume they are spraying into air (eg downstream pressure is 1 atmosphere).