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Leak Rate

Leak Rate

Leak Rate

(OP)
Hi,

I am looking to convert a pressure drop to a volumetric leak rate. I have a container which I pull (air at ambient temp)down to 1 torr then measure the change in pressure over time (i.e. leak). I need take the 50torr/min and estimate a value in cc/min. Any help is much appreciated.

RE: Leak Rate

It sounds like you have an instrumented container that is pressurized with a "fluid" and then you put the container in a vaccum for X number of minutes and measure pressure differences to find the 50 torr/min leak rate.  

Is this a compressable fluid?  

If your container fluid is a gas, one way you can do this is by using the PV=nRT equation, you can determine the change in mass of your container fluid.  Given your change in mass, you can calcuate your mass leak rate.  Once you know your mass leak rate, you can calculate your leak rate in other units.

RE: Leak Rate

(OP)
Thank You

The gas is ambient air and the volume is .03368 liters

The acceptable leak rate (pressure change) is 50torr/min.

Ya I understand I can use the universal gas law, but Im extremely rusty.

Is my math correct: (a lot of things cancel)

dV/dt = dP/dt ???

leak rate = .03368liters/760torr * 50torr/min = 2.2x10^-10 L/min ???

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