# Final State of Tank

1. Jul 23, 2012

### Art_

1. The problem statement, all variables and given/known data
Given a tank filled with gas, you are to pump out a given amount and find the final state of the tank. Given the volume, gas (non-ideal), amount of gas in tank, flow rate, temperature and pressure, all at state 1. We can find density at state 2 from the tables, but we need another quantity. So we can also solve for enthalpy.

2. Relevant equations
E_out,mass = $\int h + V/2 + gz dm$
The KE and PE can be neglected due to high flow rate, so the equation simplifies to
E_out,mass = $\int h dm$
but since h is not constant I am confused how to integrate this, and find h.

3. The attempt at a solution
I am trying to integrate numericaly but am not sure how to approch finding the intermidiate values of h.

Thank you for the help.

Last edited: Jul 23, 2012
2. Jul 24, 2012

### Simon Bridge

Well what does h depend on?

3. Jul 24, 2012

### Art_

Well h=u+pv, with u being the internal energy and p pressure and volume is constant for the tank.

4. Jul 25, 2012

### Simon Bridge

Well you need to express the things that change with m in terms of m... or, express dm in terms of the things that change.