Calculating CO2 expansion time and generated suction

AI Thread Summary
The discussion focuses on calculating the effects of opening a valve between two tanks in a CO2 system, specifically the suction created at the valve and the time required for gas redistribution. The setup includes a CO2 cartridge with a pressure regulator output of 200 psi, an 800 mL tank at 15 psi, and a second tank at 7 psi. When the valve is opened, the pressure difference will cause CO2 to flow into the second tank, raising questions about gas velocity and suction terminology. The user seeks to develop an equation incorporating various system variables, including tank volumes and pipe dimensions, to model these dynamics accurately. Clarification on the terms used and the fundamental principles of gas flow in this context is also requested.
DrFreeman
Messages
2
Reaction score
0
I need help with figuring out how to devise an equation that I'm going to plug into an algorithm for my software.
These are the components:
oeXxDht.png

CO2 cartridge pressure regulator output should be around 200 psi. Tank #1 has a volume of 800 mL, pressure is around 15 psi. There are no valves between pressure regulator and the first tank. Pressure in tank #2 is about 7 psi (soft vacuum). There is a valve between first and second tank, right at the entry point for tank #2. The question is, what will happen when the valve between tank #1 and tank #2 is opened and the CO2 from the cartridge released at the same time? I need to calculate the amount of suction created at the valve. Also, how much time will be needed until CO2 is redistributed equally throughout the system?
These are the variables: first tank volume, second tank volume, radius and length of first pipe, radius and length of second pipe and pressure regulator output value. The variables for pressure in tanks before gas release can be taken as constant values I described above (15 psi and 7 psi). Also, system will always be running at a room temperature of 25 degrees Celsius. Values for V1 and V2 above are taken as placeholders, just for this example. The goal is to plug in these 7 variables (Rout, V1, V2, r1, h1, r2, h2) into a function and get resulting suction at tank #2 entry point with an approximate gas redistribution time.

If something above is fundamentally wrong, or if I missed anything important, please let me know. I have no experience with dealing with these kind of issues.
 
Engineering news on Phys.org
DrFreeman said:
I need to calculate the amount of suction created at the valve. Also, how much time will be needed until CO2 is redistributed equally throughout the system?

DrFreeman said:
The variables for pressure in tanks before gas release can be taken as constant values I described above (15 psi and 7 psi).

DrFreeman said:
suction at tank #2 entry point
"Suction?"
 
Bystander said:
"Suction?"
I'm sorry for not clarifying. When we open valve between tank #1 and tank #2, the gas should rush in from the rest of the system to the tank #2 because of the pressure difference, right? CO2will be forced into a vacant space in tank #2? Maybe the suction isn't the right term, would gas velocity through the valve make more sense?
 
Back
Top