Valve

Simple valve

    Valve

Library

Modelica/Thermal/FluidHeatFlow/Components

Description

Simple controlled valve.

Standard characteristic Kv=f (y) is given at standard conditions (dp0, rho0),

  • either linear : Kv/Kv1 = Kv0/Kv1 + (1-Kv0/Kv1) * y/Y1
  • or exponential: Kv/Kv1 = Kv0/Kv1 * exp[log(Kv1/Kv0) * y/Y1]

where:

  • Kv0 ... min. flow @ y = 0
  • Y1 .... max. valve opening
  • Kv1 ... max. flow @ y = Y1

Flow resistance under real conditions is calculated by

V_flow**2 * rho / dp = Kv(y)**2 * rho0 / dp0

Parameters

Valve_0

NameLabelDescriptionData TypeValid Values

mo_medium

medium

Medium in the component

FromModelica('Modelica.Thermal.FluidHeatFlow.Media.Medium')
FromModelica('Modelica.Thermal.FluidHeatFlow.Media.Air_30degC')
FromModelica('Modelica.Thermal.FluidHeatFlow.Media.Air_70degC')
FromModelica('Modelica.Thermal.FluidHeatFlow.Media.MineralOil')
FromModelica('Modelica.Thermal.FluidHeatFlow.Media.Water')
FromModelica('Modelica.Thermal.FluidHeatFlow.Media.Gylcol20_20degC')
FromModelica('Modelica.Thermal.FluidHeatFlow.Media.Gylcol50_20degC')
FromModelica('Modelica.Thermal.FluidHeatFlow.Media.Water_10degC')
FromModelica('Modelica.Thermal.FluidHeatFlow.Media.Water_90degC')

mo_m

m

Mass of medium

Scalar

mo_T0

T0

Initial temperature of medium

Scalar

mo_T0fixed

T0fixed

Initial temperature guess value or fixed

Scalar

true
false

mo_tapT

tapT

Defines temperature of heatPort between inlet and outlet temperature

Scalar

mo_frictionLoss

frictionLoss

Part of friction losses fed to medium

Scalar

mo_V_flow

V_flow

V_flow

Structure

mo_V_flow/fixed

fixed

Cell of scalars

true
false

mo_V_flow/start

start

Cell of scalars

mo_T

T

T

Structure

mo_T/fixed

fixed

Cell of scalars

true
false

mo_T/start

start

Cell of scalars

mo_T_a

T_a

T_a

Structure

mo_T_a/fixed

fixed

Cell of scalars

true
false

mo_T_a/start

start

Cell of scalars

mo_T_b

T_b

T_b

Structure

mo_T_b/fixed

fixed

Cell of scalars

true
false

mo_T_b/start

start

Cell of scalars

mo_T_q

T_q

T_q

Structure

mo_T_q/fixed

fixed

Cell of scalars

true
false

mo_T_q/start

start

Cell of scalars

mo_h

h

h

Structure

mo_h/fixed

fixed

Cell of scalars

true
false

mo_h/start

start

Cell of scalars

mo_LinearCharacteristic

LinearCharacteristic

Type of characteristic

Scalar

true
false

mo_y1

y1

Max. valve opening

Scalar

mo_Kv1

Kv1

Max. flow @ y = y1

Scalar

mo_kv0

kv0

Leakage flow / max.flow @ y = 0

Scalar

mo_dp0

dp0

Standard pressure drop

Scalar

mo_rho0

rho0

Standard medium's density

Scalar

Valve_1

NameLabelDescriptionData TypeValid Values

mo__nmodifiers

Number of Modifiers

Specifies the number of modifiers

Number

mo__modifiers

Modifiers

Add new modifier

Structure

mo__modifiers/varname

Variable name

Cell of strings

'dp'
'Q_flow'
'dT'
'yLim'
'Kv'

mo__modifiers/attribute

Attribute

Cell of strings

'start'
'fixed'

mo__modifiers/value

Value

Ports

NameTypeDescriptionIO TypeNumber

flowPort_a

implicit

output

1

flowPort_b

implicit

output

2

y

implicit

input

1

See Also