How to calculate negative pressure.
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Given a container from which air is removed, how is the negative pressure inside this container calculated? Seeking advice~
The process from the beginning to reaching ultimate vacuum (where the container’s leakage rate equals the pump’s pumping capacity or the pump’s ultimate vacuum) is dynamic. I’m not quite sure how to calculate it either; the experts downstairs, please go ahead
PV=nRT=(m/MW)RT; V. MW, R, and T are all constants within the vessel, so P1/P2=m1/m2. (P1=atm, P2=vacuum); m1 is the mass under atmospheric pressure, while m2 is the remaining mass in the vessel at pressure P2. Therefore, P2=P1*(m2/m1)
This calculation is somewhat arbitrary; the volume of gas drawn is fixed, but the mass of the gas extracted varies, which requires the use of integration
An appropriate equation of state is required; for rough calculations, the ideal gas equation of state can be used: victory: