WOLFRAM SYSTEM MODELER

PilotOperatedCheckValvePilotToClose

Pilot-operated check valve with lumped volumes

Diagram

Wolfram Language

In[1]:=
SystemModel["Hydraulic.Valves.DirectionalControl.PilotOperatedCheckValvePilotToClose"]
Out[1]:=

Information

This is a model of a check valve with lumped volumes and a third port for pilot operation. The pilot ratio of the valve, kp, determines the effect of the pilot pressure on the pressure difference, i.e. how much pilot pressure "helps" the pressure on port b.

If the pressure difference is higher than pMin, the valve begins to open. When the pressure difference has reached pMax, the valve is completely opened. If the pressure is lower than pMin, the valve is closed and has only leakage flow.

Implementation

This valve basically consists of an orifice controlled by a spool.

Reference

Industrial Hydraulics Manual, 5th ed., Maumee, OH: Eaton Hydraulics Training Services, 2008 p. 188.

Parameters (9)

medium

Value: Oil()

Type: Medium

Description: Medium in the component

V

Value: 0.0001

Type: Volume (m³)

Description: Volume of control valve

Gleak

Value: 9.999999999999999e-21

Type: PressureDependentLeakage (m³/(s⋅Pa))

Description: Leakage between ports

A

Value: 0.001

Type: Area (m²)

Description: Opening area when opened

Cd

Value: 0.62

Type: Real

Description: Coefficient of discharge for the opening

kp

Value: 1

Type: Real

Description: Pilot ratio; a positive value helps port_a

pMax

Value: 100000.0

Type: Pressure (Pa)

Description: Pressure when valve is fully open

pMin

Value: 100

Type: Pressure (Pa)

Description: Pressure when valve starts to open

t1

Value: 0.001

Type: Time (s)

Description: Time constant for first-order system

Connectors (3)

port_b

Type: Port_b

Description: Port for hydraulic fluid (unfilled icon)

port_a

Type: Port_a

Description: Port for hydraulic fluid (filled icon)

port_pilot

Type: Port_a

Description: Port for hydraulic fluid (filled icon)

Components (5)

medium

Type: Medium

Description: Medium in the component

checkValve

Type: PilotOperatedCheckValve

Description: Static pilot-operated check valve

volume_a

Type: Volume

Description: Fixed volume with fluid storage

volume_b

Type: Volume

Description: Fixed volume with fluid storage

volume_pilot

Type: Volume

Description: Fixed volume with fluid storage

Used in Examples (1)

AutomaticAccumulatorDischarge

Hydraulic.Examples.Accumulators

Example circuit with automatic discharge of an accumulator