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Geith
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- TL;DR Summary
- How can I find out how long the air in a pressurised container (known pressure, volume, temperature and size of hole) will take to leave, assuming it is opened under atmospheric pressure?
I am working on a project where I have to calculate various results relating to the motion of a water bottle rocket being launched. I am currently stuck on trying to find how long the thrust period of the rocket is. The model for the rocket is as follows: It is a 2L (0.002m3 bottle filled with air at a pressure of 7 Bar, one third of the bottle is to be filled with water, however for simplicity's sake I am willing to assume that the volume of the air in the bottle is a constant 2L, and that the temperature remains constant (room temp. 293K). I also know that the area of the hole in the bottle is about 3×10-4 m2.
Using this information, is it possible to determine the time that it will take for the pressure in the bottle to reach equilibrium? I am assuming it will follow a somewhat inverse exponential model, where the pressure will never truly reach equilibrium, but will get exceptionally close at a certain time (similar to time constants in a capacitor).
Feel free to ask for additional information.
Thanks.
Using this information, is it possible to determine the time that it will take for the pressure in the bottle to reach equilibrium? I am assuming it will follow a somewhat inverse exponential model, where the pressure will never truly reach equilibrium, but will get exceptionally close at a certain time (similar to time constants in a capacitor).
Feel free to ask for additional information.
Thanks.