Estimate Volume using ideal gas law

Jul 2014
An ideal gas (H2) filled vessel is a part of a chemical process. The volume of vessel is depending on product status and nobody knows what is the exact volume? I think we can calculate it using ideal gas law and with help of pressure and temperature measurement.
It is worth telling a pipe is open to vessel maintaining the pressure and its flow rate is also being measured.
my formula is:
When T1 and T2 are gas temperature before and after a while. t is time and Q is inlet gas flow rate. Tn0 is temperature of inlet gas while coming into vessel. Then:
V= Qt(T2/Tn0)/ ((P2/P1)-(T2/T1))
Please tell me your idea about this formula. Can it be a practical method to calculate volume indirectly or not?
Feel free to ask (P2/P1)-(T2/T1)=Qt(T2/Tn0)/V-E any question.


Apr 2008
Bedford, England
There are a couple of issues:
You indicate the feed pipe is maintaining pressure.
Does this not imply that pressure is constant (P1=P2)?
Is the chemical process exothermic or endothermic?
Does the product of the chemical reaction take up less volume than the supplied gas?
Is the product being removed from the vessel?

Since you are dealing with a chemical reaction, it might be useful to consider the molar quantities of feed stock and product.