Based on the ideal gas law, it should be a function of MW. 1 mole of gas at STP is a constant volume, and the weight is equal to MW, so the SG is proportional to MW, at least when the gases are behaving close to the ideal gas law.
Katmar,
No, I think the vendor is right, in that he is referring to STANDARD cfm. The pressure decreases the flow as the square root, because of density, but it increases the flow in direct proportion because the standard volume is getting larger as the actual volume stays the same.
Never mind, I have it now.
I am looking at STANDARD cfm, so changing SG does not change the moles of gas, but changing P does. If I pressurize, I should decrease flow by sqrt(density) but increase directly proportional to Pabs, with the net being an increase by sqrt(Pabs), since density is...
Thanks for the responses.
I understand the specific gravity part now - it is a function of molecular weight, not actual density.
I think I have a good grasp of the ideal gas law to calculate variations in actual flow with temperature and pressure. This is really a general question about...
I am looking at pressure corrections for gas flow meters. The vendor says that the reading should be multiplied by sqrt(Pactual/Pcal), where Pcal is the pressure the meter was calibrated at. That says if the pressure rises, the actual flow is higher than the reading.
But it also says that the...
