It is worth telling a pipe is open to vessel maintaining the pressure and its flow rate is also being measured.

my formula is:

(P2/P1)-(T2/T1)=Qt(T2/Tn0)/V

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.