What is the differance between an atm-cc/sec and a scc/sec.

[edgyone]

I am guessing there is none, but I would like to be sure and find out why there the two units exist.

 

[mbeychok]

edgyone:

I am assuming that you are referring to terminology that is commonly used to define small gas flow rates in the leak detection field. If that is correct:

(1) atm-cc/sec refers to a gas leak rate of cubic centimeters per second measured at atmospheric pressure. Other terms used are torr-cc/sec, bar-cc/sec and scc/sec.

(2) scc/sec refers to a gas leak rate of standard cubic centimeters per sec.

(3) It is impossible to convert one of those terms to another unless we know the reference temperature as well as the pressure that applies to each of them. The word "standard" is meaningless without a reference temperature and pressure. The words "atm-cc", "torr-cc" and "bar-cc" are also meaningless without a reference temperature.



Milton Beychok
(Contact me at www.air-dispersion.com)
.

 

[quark]

The advantage of Pre-vol/time is to fix a standard for leak rates irrespective of the container volume.

 

[MortenA]

perhaps its not atm-cc/sec but _actual_ cc/sec?

Then its because scc/sec is actually just a methode of stating the molar flow rate - whereas acutaul cc/sec is for calculating velocity.

Best regards

Morten