Two Way Valve - MapleSim Help

Online Help

All Products    Maple    MapleSim


Two-Way Two-Position Valve

Two-position valve that controls flow between two ports

 

Description

Connections

Parameters

Description

The Two-Way Two-Position Valve component allows flow between ports A and P with two positions to control the flow.

The real input s controls the position of the value. An input of 0 corresponds to position 0, an input of 1 to position 1. Intermediates values produce an averaged position, with the transition length set by the band parameter.

The following figure shows how s and band effect the valve opening.

Formulation Approaches

Two approaches were taken for formulation of the flow equation inside the device. When the boolean parameter Use constant Cd is true, a constant coefficient of discharge (Cd) is used, otherwise a variable coefficient of discharge with maximum value (Cdmax) and a critical flow number (Critno) are used.

Connections

Name

Description

Modelica ID

portA

Hydraulic port to path A

portA

portP

Hydraulic port for pump

portP

s

Real input signal that controls valve position

s

Parameters

General

Name

Default

Units

Description

Modelica ID

Amax

1·10−4

m2

Maximum orifice opening area

Amax

Amin

1·10−12

m2

Minimum orifice opening area (leakage)

Amin

band

0.1

 

Transition length in normalized spool displacement

band

Orifice

Name

Default

Units

Description

Modelica ID

Use constant Cd

true

 

True (checked) means a constant coefficient of discharge is implemented, otherwise a variable Cd is used in flow calculation

UseConstantCd

Cd

0.7

 

Flow-discharge coefficient; used when Use constant Cd is true

Cd

Cr

12

 

Reynolds number at critical flow; used when Use constant Cd is true

ReCr

Cdmax

0.7

 

Maximum flow-discharge coefficient; used when Use constant Cd is false

Cd_max

Critno

1000

 

Critical flow number; used when Use constant Cd is false

Crit_no

Optional Volumes

Name

Default

Units

Description

Modelica ID

Use volume A

false

 

True (checked) means a hydraulic volume chamber is added to portA

useVolumeA

VA

1·10−6

m3

Volume of chamber A

Va

Use volume P

false

 

True (checked) means a hydraulic volume chamber is added to portP

useVolumeP

VP

1·10−6

m3

Volume of chamber P

Vb

For more information see Port Volumes.

See Also

Hydraulics Library

Valves