A Temperature and pressure change in an air vessel

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The discussion focuses on modeling an air vessel with constant volume during the charging and discharging of compressed air. The user seeks confirmation on the suitability of specific equations related to air mass, mass flow rates, and temperature. Participants request derivations and clarification on whether charging and discharging occur simultaneously. The user references an equation from a published Elsevier paper and expresses gratitude for feedback. Confirmation of the temperature equation using the open system version of the first law of thermodynamics is provided, supporting the model's validity.
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Hello All,

I am trying to model an air vessel with a constant volume during charging and discharging with compressed air. Are the equations in the attached photo are suitable?
where m is the air mass, Gc and Gt are the mass flow rate in and out of the air vessel with a volume V. Tac is the temperature of the Air in air storage device.
 

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AmeenBassam said:
Hello All,

I am trying to model an air vessel with a constant volume during charging and discharging with compressed air. Are the equations in the attached photo are suitable?
where m is the air mass, Gc and Gt are the mass flow rate in and out of the air vessel with a volume V. Tac is the temperature of the Air in air storage device.
Let's see your derivation. Also, are the charging and discharging occurring simultaneously?
 
Chestermiller said:
Let's see your derivation. Also, are the charging and discharging occurring simultaneously?
I found this equation in a published paper in Elsevier and I just wanted to make sure of it and thank you for your reply.
 
AmeenBassam said:
I found this equation in a published paper in Elsevier and I just wanted to make sure of it and thank you for your reply.
Using the open system version of the 1st law of thermodynamics, I confirmed the temperature equation, even for combined charging and discharging.
 
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