Single-Acting Actuator (TL)

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Single-acting linear actuator in a thermal liquid network.

single acting actuator tl

Description

Block Single-Acting Actuator (TL) simulates a linear actuator whose piston is controlled by a thermal liquid chamber. The actuator creates a reciprocating motion of the piston, the force on which is determined by the overpressure of the thermal liquid chamber.

The figure shows the main components of the actuator for different values of the Mechanical orientation parameters. Port A represents the entrance to the thermal liquid chamber. Port R is associated with the piston and port C is associated with the actuator housing. Port H provides the thermal interaction between the thermal liquid and the environment.

single acting actuator tl 2

single acting actuator tl 1

Relocation

The piston movement is determined by the displacement of port R relative to port C. The direction of piston movement is set by the Mechanical orientation parameters. Piston movement is neutral (equal to 0) when the chamber volume is equal to Dead volume.

The direction of piston movement depends on the Mechanical orientation parameters. If the mechanical orientation is positive, the piston movement will be positive with respect to the actuator body when the gauge pressure at port A is positive. The direction of motion is reversed when the mechanical orientation is negative.

Rigid stop model

Piston movement is limited by a pair of rigid stops located within the piston stroke. The block uses the same hard stop model as the block Translational Hard Stop, and takes into account the damping and stiffness coefficients at both ends of the piston stroke.

If piston travel is positive, the lower hard stop is at , and the upper hard stop is at . If the piston travel is negative, the lower hard stop is at and the upper hard stop is at .

Damper

This block can simulate a damper at the extremes of the piston stroke. Select the Cylinder end cushioning parameter to slow the piston as it approaches the maximum elongation defined by the Piston stroke parameter.

Friction

This block can simulate friction against piston movement. If the Cylinder friction parameters are set, the resulting friction is a combination of Stribeck, Coulomb and viscosity effects. The unit measures the pressure difference between chamber pressure and ambient pressure.

Subcomponents of the unit

Block Single-Acting Actuator (TL) consists of blocks:

The structure diagram of the actuator is shown in the schematic diagram.

single acting actuator tl 1

If the parameters Cylinder friction or Cylinder end cushioning are checked, the block composition also includes Cylinder Friction (TL) or Cylinder Cushion (TL) blocks.

single acting actuator tl 2

Ports

Conserving

# H — heat port
heat

Details

A port relating to the thermal conductivity of a thermal liquid.

Program usage name

thermal_port

# C — drive housing
translational mechanics

Details

Mechanical progressive port corresponding to the actuator housing.

Program usage name

case_flange

# A — inlet or outlet for thermal liquid
thermal liquid

Details

The port corresponding to the thermal liquid entering or leaving the chamber.

Program usage name

port

# R — actuator piston
translational mechanics

Details

A mechanical progressive port corresponding to the actuator piston.

Program usage name

rod_flange

Output

# p — piston position
scalar

Details

Piston position in m.

Data types	`Float64`.
Complex numbers support	No

Parameters

Actuator

# Mechanical orientation — piston travel direction
Pressure at A causes positive displacement of R relative to C | Pressure at A causes negative displacement of R relative to C

Details

Determines the direction of piston displacement. Options for selection:

`Pressure at A causes positive displacement of R relative to C' - piston displacement is positive if the fluid volume in port A increases. This corresponds to the movement of the rod out of the cylinder.
Pressure at A causes negative displacement of R relative to C - piston movement is negative if the volume of fluid in port A increases. This corresponds to movement of the rod inside the cylinder.

Values	`Pressure at A causes positive displacement of R relative to C` \| `Pressure at A causes negative displacement of R relative to C`
Default value	`Pressure at A causes positive displacement of R relative to C`
Program usage name	`orientation`
Evaluatable	No

# Piston cross-sectional area — cross-sectional area of the piston rod
m^2 | cm^2 | ft^2 | in^2 | km^2 | mi^2 | mm^2 | um^2 | yd^2

Details

Cross-sectional area of the piston rod.

Values	`m^2` \| `cm^2` \| `ft^2` \| `in^2` \| `km^2` \| `mi^2` \| `mm^2` \| `um^2` \| `yd^2`
Default value	`0.01 m^2`
Program usage name	`piston_area`
Evaluatable	Yes

# Piston stroke — piston stroke
m | cm | ft | in | km | mi | mm | um | yd

Details

Maximum possible piston travel.

Values	`m` \| `cm` \| `ft` \| `in` \| `km` \| `mi` \| `mm` \| `um` \| `yd`
Default value	`0.1 m`
Program usage name	`stroke`
Evaluatable	Yes

# Dead volume — volume of liquid in the chamber, at which the piston movement is equal to 0
l | gal | igal | m^3 | cm^3 | ft^3 | in^3 | km^3 | mi^3 | mm^3 | um^3 | yd^3 | N*m/Pa | N*m/bar | lbf*ft/psi | ft*lbf/psi

Details

Volume of liquid at piston movement value 0. This fluid volume corresponds to the position of the piston when it is up against the actuator end cap.

Values	`l` \| `gal` \| `igal` \| `m^3` \| `cm^3` \| `ft^3` \| `in^3` \| `km^3` \| `mi^3` \| `mm^3` \| `um^3` \| `yd^3` \| `Nm/Pa` \| `Nm/bar` \| `lbfft/psi` \| `ftlbf/psi`
Default value	`1e-05 m^3`
Program usage name	`dead_volume`
Evaluatable	Yes

# Environment pressure specification — method of setting the ambient pressure
Atmospheric pressure | Specified pressure

Details

Method of setting the ambient pressure. The Atmospheric pressure option sets the ambient pressure to 0.101325 MPa.

Values	`Atmospheric pressure` \| `Specified pressure`
Default value	`Atmospheric pressure`
Program usage name	`pressure_type`
Evaluatable	No

# Environment pressure — ambient pressure
Pa | GPa | MPa | atm | bar | kPa | ksi | psi | uPa | kbar

Details

User-defined ambient pressure.

Dependencies

To use this parameter, set the Environment pressure specification parameters to Specified pressure.

Values	`Pa` \| `GPa` \| `MPa` \| `atm` \| `bar` \| `kPa` \| `ksi` \| `psi` \| `uPa` \| `kbar`
Default value	`0.101325 MPa`
Program usage name	`p_specified`
Evaluatable	Yes

Hard Stop

# Hard stop model — selecting the model of the hard stop
Stiffness and damping applied smoothly through transition region, damped rebound | Full stiffness and damping applied at bounds, undamped rebound | Full stiffness and damping applied at bounds, damped rebound

Details

Model selection for the force acting on the piston when it is at the end positions. For more information, see the block Translational Hard Stop.

Values	`Stiffness and damping applied smoothly through transition region, damped rebound` \| `Full stiffness and damping applied at bounds, undamped rebound` \| `Full stiffness and damping applied at bounds, damped rebound`
Default value	`Stiffness and damping applied smoothly through transition region, damped rebound`
Program usage name	`hardstop_model`
Evaluatable	No

# Hard-stop stiffness coefficient — stiffness factor
N/m | lbf/ft | lbf/in

Details

Piston stiffness coefficient.

Values	`N/m` \| `lbf/ft` \| `lbf/in`
Default value	`1e10 N/m`
Program usage name	`k_hard_stop`
Evaluatable	Yes

# Hard-stop damping coefficient — damping factor
kg/s | N*s/m | N/(m/s) | lbf/(ft/s) | lbf/(in/s)

Details

Piston damping factor.

Values	`kg/s` \| `N*s/m` \| `N/(m/s)` \| `lbf/(ft/s)` \| `lbf/(in/s)`
Default value	`150.0 N*s/m`
Program usage name	`C_hard_stop`
Evaluatable	Yes

# Transition region — range of action of the rigid stop model
m | cm | ft | in | km | mi | mm | um | yd

Details

The operating range of the hard stop model. Outside this range, the Hard stop model does not apply to the extreme piston positions and no additional force is applied to the piston by the stop.

Dependencies

To use this parameter, set the Hard stop model parameters to `Stiffness and damping applied smoothly through transition region, damped rebound'.

Values	`m` \| `cm` \| `ft` \| `in` \| `km` \| `mi` \| `mm` \| `um` \| `yd`
Default value	`0.1 mm`
Program usage name	`transition_region`
Evaluatable	Yes

Cushion

# Cylinder end cushioning — option to simulate piston braking due to damper action

Details

Select this checkbox to enable piston deceleration at its extreme positions. For more information, see the block Cylinder Cushion (TL).

Default value	`false (switched off)`
Program usage name	`enable_cylinder_cushion`
Evaluatable	No

# Cushion plunger cross-sectional area — cross-sectional area of the damping plug
m^2 | cm^2 | ft^2 | in^2 | km^2 | mi^2 | mm^2 | um^2 | yd^2

Details

Cross-sectional area of the damping plug.

Dependencies

To use this parameter, select the Cylinder end cushioning parameters check box.

Values	`m^2` \| `cm^2` \| `ft^2` \| `in^2` \| `km^2` \| `mi^2` \| `mm^2` \| `um^2` \| `yd^2`
Default value	`0.0001 m^2`
Program usage name	`plunger_area`
Evaluatable	Yes

# Cushion plunger length — damping plug length
m | cm | ft | in | km | mi | mm | um | yd

Details

Length of the damping plug.

Dependencies

To use this parameter, select the Cylinder end cushioning parameters check box.

Values	`m` \| `cm` \| `ft` \| `in` \| `km` \| `mi` \| `mm` \| `um` \| `yd`
Default value	`0.001 m`
Program usage name	`plunger_length`
Evaluatable	Yes

# Cushion orifice area — area of the opening between the damper chambers
m^2 | cm^2 | ft^2 | in^2 | km^2 | mi^2 | mm^2 | um^2 | yd^2

Details

The area of the opening between the damper chambers.

Dependencies

To use this parameter, select the Cylinder end cushioning parameters check box.

Values	`m^2` \| `cm^2` \| `ft^2` \| `in^2` \| `km^2` \| `mi^2` \| `mm^2` \| `um^2` \| `yd^2`
Default value	`1e-06 m^2`
Program usage name	`cushioning_valve_area`
Evaluatable	Yes

# Leakage area between plunger and cushion sleeve — clearance area between damper plug and bushing
m^2 | cm^2 | ft^2 | in^2 | km^2 | mi^2 | mm^2 | um^2 | yd^2

Details

The clearance area between the damper plunger and the sleeve. Parameters maintains the computational stability of the simulation by ensuring flow continuity.

Dependencies

To use this parameter, select the Cylinder end cushioning parameters checkbox.

Values	`m^2` \| `cm^2` \| `ft^2` \| `in^2` \| `km^2` \| `mi^2` \| `mm^2` \| `um^2` \| `yd^2`
Default value	`1e-07 m^2`
Program usage name	`plunger_leakage_area`
Evaluatable	Yes

# Check valve cracking pressure differential — differential pressure at which the check valve starts to open
Pa | GPa | MPa | atm | bar | kPa | ksi | psi | uPa | kbar

Details

The pressure above which the damper actuates. When the pressure difference between port A and meets or exceeds this parameters value, the damper check valve will open.

Dependencies

To use this parameter, select the Cylinder end cushioning parameters check box.

Values	`Pa` \| `GPa` \| `MPa` \| `atm` \| `bar` \| `kPa` \| `ksi` \| `psi` \| `uPa` \| `kbar`
Default value	`0.01 MPa`
Program usage name	`delta_p_crack`
Evaluatable	Yes

# Check valve maximum pressure differential — pressure drop required to fully open the check valve
Pa | GPa | MPa | atm | bar | kPa | ksi | psi | uPa | kbar

Details

Maximum differential pressure of the damper check valve. This parameters sets the upper pressure limit to keep the system pressure realistic.

Dependencies

To use this parameter, select the Cylinder end cushioning parameters check box.

Values	`Pa` \| `GPa` \| `MPa` \| `atm` \| `bar` \| `kPa` \| `ksi` \| `psi` \| `uPa` \| `kbar`
Default value	`0.1 MPa`
Program usage name	`delta_p_max`
Evaluatable	Yes

# Check valve maximum area — area of fully open check valve
m^2 | cm^2 | ft^2 | in^2 | km^2 | mi^2 | mm^2 | um^2 | yd^2

Details

The cross-sectional area of the check valve orifice in the fully open position.

Dependencies

To use this parameter, select the Cylinder end cushioning parameters check box.

Values	`m^2` \| `cm^2` \| `ft^2` \| `in^2` \| `km^2` \| `mi^2` \| `mm^2` \| `um^2` \| `yd^2`
Default value	`0.0001 m^2`
Program usage name	`check_valve_max_area`
Evaluatable	Yes

# Check valve leakage area — leakage area with fully closed check valve
m^2 | cm^2 | ft^2 | in^2 | km^2 | mi^2 | mm^2 | um^2 | yd^2

Details

Total possible leakage area with the check valve fully closed. Any area smaller than this value increases smoothly to the specified leakage area. This value contributes to computational stability by maintaining flow continuity.

Dependencies

To use this parameter, select the Cylinder end cushioning parameters checkbox.

Values	`m^2` \| `cm^2` \| `ft^2` \| `in^2` \| `km^2` \| `mi^2` \| `mm^2` \| `um^2` \| `yd^2`
Default value	`1e-10 m^2`
Program usage name	`check_valve_leakage_area`
Evaluatable	Yes

# Smoothing factor — numerical smoothing factor

Details

A continuous smoothing factor that provides a smooth opening by correcting the valve characteristic in the nearly open and nearly closed positions. Set a non-zero value less than one to increase the stability of the simulation in these modes.

Default value	`0.01`
Program usage name	`smoothing_factor`
Evaluatable	Yes

Friction

# Cylinder friction — option for modelling friction during piston movement

Details

Whether the friction of the piston during movement is taken into account. The block friction force is made up of the Stribeck force, Coulomb force and viscosity.

Select this check box to include piston friction during movement. The block friction force is the sum of the Stribeck force, Coulomb force, and viscosity. For more information, see the block Cylinder Cushion (TL).

Default value	`false (switched off)`
Program usage name	`enable_friction`
Evaluatable	No

# Breakaway to Coulomb friction force ratio — the ratio of the detachment force to the Coulomb friction force

Details

The ratio of the detachment force to the Coulomb friction force.

Dependencies

To use this parameter, select the Cylinder friction parameters check box.

Default value	`1.2`
Program usage name	`Coulomb_breakaway_ratio`
Evaluatable	Yes

# Breakaway friction velocity — friction threshold
fpm | fps | kph | mph | m/s | cm/s | ft/s | in/s | km/s | mi/s | mm/s

Details

Threshold value for movement against friction force.

Dependencies

To use this parameter, select the Cylinder friction parameters check box.

Values	`fpm` \| `fps` \| `kph` \| `mph` \| `m/s` \| `cm/s` \| `ft/s` \| `in/s` \| `km/s` \| `mi/s` \| `mm/s`
Default value	`0.1 m/s`
Program usage name	`v_breakaway`
Evaluatable	Yes

# Preload force — initial force in the cylinder during seal assembly, N
N | kN | lb | mN | dyn | lbf

Details

Initial force in the cylinder due to the seal assembly. The unit uses this parameter to calculate the Coulomb friction force.

Dependencies

To use this parameter, select the Cylinder friction parameters check box.

Values	`N` \| `kN` \| `lb` \| `mN` \| `dyn` \| `lbf`
Default value	`20.0 N`
Program usage name	`F_preload`
Evaluatable	Yes

# Coulomb friction force coefficient — Coulomb friction force coefficient
m^2 | cm^2 | ft^2 | in^2 | km^2 | mi^2 | mm^2 | um^2 | yd^2 | N/Pa

Details

Coulomb friction force coefficient. The block uses this parameters to calculate the Coulomb friction force.

Dependencies

To use this parameter, select the Cylinder friction parameters checkbox.

Values	`m^2` \| `cm^2` \| `ft^2` \| `in^2` \| `km^2` \| `mi^2` \| `mm^2` \| `um^2` \| `yd^2` \| `N/Pa`
Default value	`1e-06 N/Pa`
Program usage name	`Coulomb_coefficient`
Evaluatable	Yes

# Viscous friction coefficient — viscous friction coefficient
kg/s | N*s/m | N/(m/s) | lbf/(ft/s) | lbf/(in/s)

Details

Coefficient of viscous friction. This parameter is used to calculate the viscous friction force.

Dependencies

To use this parameter, select the Cylinder friction parameters check box.

Values	`kg/s` \| `N*s/m` \| `N/(m/s)` \| `lbf/(ft/s)` \| `lbf/(in/s)`
Default value	`100.0 N*s/m`
Program usage name	`viscous_coefficient`
Evaluatable	Yes

Initial Conditions

# Initial piston displacement — initial piston position
m | cm | ft | in | km | mi | mm | um | yd

Details

Piston position at the beginning of the simulation.

Dependencies

To use this parameter, set the Piston displacement parameters to `Calculate from velocity of port R relative to port C.

Values	`m` \| `cm` \| `ft` \| `in` \| `km` \| `mi` \| `mm` \| `um` \| `yd`
Default value	`0.0 m`
Program usage name	`offset`
Evaluatable	Yes

# Fluid dynamic compressibility — fluid compressibility modelling option

Details

Select this checkbox to include changes in fluid density due to fluid compressibility. If Fluid dynamic compressibility is checked, changes due to the mass flow rate of the fluid in the block are calculated in addition to density changes due to pressure changes. In the Isothermal liquid library, all blocks calculate density as a function of pressure.

Default value	`true (switched on)`
Program usage name	`dynamic_compressibility`
Evaluatable	No

# Initial liquid pressure — initial fluid pressure for compressible fluids
Pa | GPa | MPa | atm | bar | kPa | ksi | psi | uPa | kbar

Details

Initial fluid pressure for compressible fluids.

Dependencies

To use this parameter, select the Fluid dynamic compressibility checkbox.

Values	`Pa` \| `GPa` \| `MPa` \| `atm` \| `bar` \| `kPa` \| `ksi` \| `psi` \| `uPa` \| `kbar`
Default value	`0.101325 MPa`
Program usage name	`p_start`
Evaluatable	Yes

Details

Initial fluid pressure for compressible fluids.

Dependencies

To use this parameter, select the Fluid dynamic compressibility checkbox.

Values	`K` \| `degC` \| `degF` \| `degR` \| `deltaK` \| `deltadegC` \| `deltadegF` \| `deltadegR`
Default value	`293.15 K`
Program usage name	`T_start`
Evaluatable	Yes