Controlled Pressure Difference Source (G)
The source of the pressure drop.
blockType: AcausalFoundation.Gas.Sources.PressureDifference
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Controlled Pressure Difference Source (G) Path in the library: |
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Pressure Difference Source (G) Path in the library: |
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Description
Block Controlled Pressure Difference Source (G) It is an ideal source of mechanical energy in the gas network. The source can maintain a constant pressure drop at its ports regardless of the mass flow through the source. There is no gas resistance and no heat exchange with the environment. A positive differential pressure value means that the pressure at port B is greater than the pressure at port A.
If the parameter Controlled source If it is switched on, the pressure drop is controlled by an input scalar signal on the P port. If the parameter Controlled source If it is switched off, the pressure drop is constant and is set by the parameter Pressure difference, Pa.
You can choose whether the source does work with the gas flow.:
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If the source is isentropic (parameter Isentropic power added is included), then the isentropic ratio depends on the model of gas properties.
The gas model The equation The ideal gas
Semi-ideal gas
Real gas
The power given to the gas flow is based on the specific total enthalpy associated with the isentropic process.
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If the source is not doing any work (parameter Isentropic power added off), then the basic equation is written based on the fact that the specific total enthalpy is the same on both sides of the source. This is equally true for all three models of gas properties.
Power supplied to the gas stream .
The following notation is used in the equations:
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— specific heat capacity at constant pressure, J/(kg*K);
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— specific enthalpy, J;
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— mass flow rate, kg/s (the flow rate associated with the port is positive when gas enters the unit through this port);
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— pressure, Pa;
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— universal gas constant, J/(mol*K);
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— specific entropy, J/(kg*K);
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— temperature, K;
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— flow rate, m/s;
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— the coefficient of compressibility;
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— the power supplied to the gas flow through the source, W.
The A and B indexes indicate the corresponding port.
Ports
Conserving
#
A
—
Source Input
gas
Details
Gas port. A positive pressure drop causes the pressure at port B to be greater than the pressure at port A.
| Program usage name |
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#
B
—
Source Input
gas
Details
Gas port. A positive pressure drop causes the pressure at port B to be greater than the pressure at port A.
| Program usage name |
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Input
#
P
—
differential pressure setting signal, Pa
scalar
Details
The input scalar signal that determines the pressure drop of the gas in the source. A positive signal on port P causes the pressure on port B to be greater than the pressure on port A.
Dependencies
To use this port, check the box Controlled source.
| Data types |
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| Complex numbers support |
I don’t |
Parameters
Parameters
# Controlled source — is the pressure drop set by the input signal
Details
Determines how the pressure drop will be set:
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If this option is selected, the pressure drop is set by the input signal P.
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If this option is not selected, the constant pressure drop is set by Pressure differential.
| Default value |
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| Program usage name |
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| Evaluatable |
No |
#
Pressure differential —
constant pressure drop
Pa | uPa | hPa | kPa | MPa | GPa | kgf/m^2 | kgf/cm^2 | kgf/mm^2 | mbar | bar | kbar | atm | ksi | psi | mmHg | inHg
Details
The pressure drop of the gas at the source ports.
Dependencies
To use this option, uncheck the box. Controlled source.
| Units |
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| Default value |
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| Program usage name |
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| Evaluatable |
Yes |
# Isentropic power added — is the source doing the job
Details
Sets whether the source is working with the gas flow.:
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If this option is selected, the source performs isentropic work with the gas to maintain the set mass flow rate regardless of the pressure drop. Use this parameter to represent the ideal pump or compressor and to properly account for energy consumption and output, especially in closed-loop systems.
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If this option is not selected, the source does not perform any work with the flow, neither adding nor subtracting power, regardless of the mass flow rate generated by the source. Use this option to set the desired flow mode at the system entrance without affecting the flow temperature.
| Default value |
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| Program usage name |
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| Evaluatable |
No |
#
Cross-sectional area at port A —
the cross-sectional area normal to the flow path at port A
m^2 | um^2 | mm^2 | cm^2 | km^2 | in^2 | ft^2 | yd^2 | mi^2 | ha | ac
Details
The cross-sectional area normal to the flow path at port A.
| Units |
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| Default value |
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| Program usage name |
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| Evaluatable |
Yes |
#
Cross-sectional area at port B —
the cross-sectional area normal to the flow path at port B
m^2 | um^2 | mm^2 | cm^2 | km^2 | in^2 | ft^2 | yd^2 | mi^2 | ha | ac
Details
The cross-sectional area normal to the flow path at port B.
| Units |
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| Default value |
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| Program usage name |
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| Evaluatable |
Yes |