Pressure drop inside container - Interesting

[shrikeerthi]

Hai everyone,

I have a container which initially contains air. I start flooding it with a gas at a constant mass flow rate. I assume that the gas mixes with the content of the container at once ie I assume a homogeneous mixture. The container has an exit pipe to vent the pressure built-up inside the container during the injection of the gas. The exit pipe leads the excess mixture to the open atmosphere.

Now my task is to compute the mass flow rate of the mixture through the exit pipe as well as the pressure drop inside the container as a function of time. Given that the substance is a gas, compressibility has to be taken into account. Does anybody have a solution? Thanks in advance for any help.

With Regards,
sk

[Tim_Lou]

PV=nRT
so, PV=mass *(RT/molar mass)
(temperature is constant, right?)
differentiate both sides with respect with time
Volume of containers * dP/dT = (RT/molar mass) * dmass/dt

im not sure if it is correct though... correct me if im wrong.
edit: wait, this is not dP/dT with respect to time..... what was i doing?!...

[shrikeerthi]

Thanks Lou for your reply. I forgot to mention that while the container is initially at room temperature, the injected gas is at a different temperature from the normal room temperature. So there is change in temperature inside the container in additon to change in pressure.