WOLFRAM SYSTEM MODELER
PumpVariableModel of a pump with variable displacement and volumes |
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Diagram
Wolfram Language
In[1]:=
SystemModel["Hydraulic.PumpsAndMotors.PumpVariable"]
Out[1]:=
Information
This is a model of a pump with volumes, variable displacement setting, friction, and internal and external leakage. The axial speed is proportional to the flow rate:
The torque is proportional to the pressure difference:
where
The signal is limited to +/-1 and controls the flow according to the table below:
The torque is proportional to the pressure difference:
where
 | : | Mass flow rate | |
 | : | Fluid density | |
| D | : | Maximum displacement | |
| u | : | Displacement setting | |
 | : | Pressure difference between the ports | |
 | : | Torque | |
 | : | Angular velocity |
The signal is limited to +/-1 and controls the flow according to the table below:
| u>=1 | : | Maximum flow from port a to port b | |
| u=0 | : | Only leakage flow from port a to port b | |
| u<=-1 | : | Maximum flow from port b to port a |
Limitations
Volumetric efficiency is not included in the model.Reference
Industrial Hydraulics Manual, 5th ed., Maumee, OH: Eaton Hydraulics Training Services, 2008 p. 164.Parameters (8)
| medium |
Value: Oil() Type: Medium Description: Medium in the component |
|---|---|
| D |
Value: Type: Volume (m³) Description: Displacement per revolution |
| externalLeakage |
Value: 1e-12 Type: PressureDependentLeakage (m³/(s⋅Pa)) Description: Leakage between cylinders |
| internalLeakage |
Value: 1e-12 Type: PressureDependentLeakage (m³/(s⋅Pa)) Description: Leakage between cylinders |
| frictionD |
Value: 1 Type: RotationalDampingConstant (N⋅m⋅s/rad) Description: Viscous friction |
| J |
Value: 1 Type: MomentOfInertia (kg⋅m²) Description: Moments of inertia |
| tankPressure |
Value: 100000.0 Type: Pressure (Pa) Description: Tank pressure |
| V |
Value: 0.0001 Type: Volume (m³) Description: Volume |
Connectors (4)
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port_b |
Type: Port_b Description: Port for hydraulic fluid (unfilled icon) |
|---|---|---|
 |
port_a |
Type: Port_a Description: Port for hydraulic fluid (filled icon) |
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flange |
Type: Flange_a Description: One-dimensional rotational flange of a shaft (filled circle icon) |
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e |
Type: RealInput Description: Displacement setting between -1 and 1 |
Components (13)
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medium |
Type: Medium Description: Medium in the component |
|---|---|---|
 |
volume_b |
Type: Volume Description: Fixed volume with fluid storage |
|
volume_a |
Type: Volume Description: Fixed volume with fluid storage |
 |
inertia |
Type: Inertia Description: 1D-rotational component with inertia |
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friction |
Type: Damper Description: Linear 1D rotational damper |
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pumpMotorVariable |
Type: BasicDisplacementMachine Description: Model of a pump/motor with variable displacement and no volumes |
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externalLeakage_b |
Type: RestrictionLaminar Description: Laminar restriction using conductance |
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tank_b |
Type: Tank Description: Simple tank with constant pressure |
|
tank_a |
Type: Tank Description: Simple tank with constant pressure |
|
externalLeakage_a |
Type: RestrictionLaminar Description: Laminar restriction using conductance |
|
internalLeakage_ab |
Type: RestrictionLaminar Description: Laminar restriction using conductance |
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fixed1 |
Type: Fixed Description: Flange fixed in housing at a given angle |
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limiter1 |
Type: Limiter Description: Limit the range of a signal |
Used in Examples (1)
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Hydraulic.Examples.Rotation Example circuit of a pump driving a motor |