Energy Balance on Pressurizing a Tank
Energy Balance on Pressurizing a Tank
A gas flows through a pipe into an insulated tank. The tank is initially at a lower pressure than the gas in the pipe and at a different temperature. When the valve to the tank is opened, the gas fills the tank until the pressures equalize, and the valve is then closed.
The tank can initially contain nitrogen (), treated as an ideal gas, with additional nitrogen added from the line. Alternatively, the tank can initially contain a water vapor/liquid mixture with superheated steam added from the line. With water in the tank, both the volume of the tank (0.1 ) and the initial mass of water (1 kg) are fixed, and thus as the initial tank pressure is changed (but the mass does not change), the quality (vapor mass fraction) of the water in the tank changes. When the valve is opened, then the mass in the tank changes. The flowing gas conditions and the initial tank conditions can be changed. For the system with water, the temperature of the vapor/liquid mixture in the tank cannot be varied, because the contents are at the saturation temperature.
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2
3
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Use the "open/close valve" reset button to go back to the initial conditions before the valve was opened, and click "open/close valve" to let the gas flow into the tank.