WOLFRAM SYSTEMMODELER

Valve

Simple valve

Wolfram Language

In[1]:=
Click for copyable input
SystemModel["Modelica.Thermal.FluidHeatFlow.Components.Valve"]
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Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

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

Connectors (3)

flowPort_a

Type: FlowPort_a

Description:

flowPort_b

Type: FlowPort_b

Description:

y

Type: RealInput

Description:

Parameters (12)

medium

Value: FluidHeatFlow.Media.Medium()

Type: Medium

Description: Medium in the component

m

Value:

Type: Mass (kg)

Description: Mass of medium

T0

Value:

Type: Temperature (K)

Description: Initial temperature of medium

T0fixed

Value: false

Type: Boolean

Description: Initial temperature guess value or fixed

tapT

Value: 1

Type: Real

Description: Defines temperature of heatPort between inlet and outlet temperature

LinearCharacteristic

Value:

Type: Boolean

Description: Type of characteristic

y1

Value:

Type: Real

Description: Max. valve opening

Kv1

Value:

Type: VolumeFlowRate (m³/s)

Description: Max. flow @ y = y1

kv0

Value:

Type: Real

Description: Leakage flow / max.flow @ y = 0

dp0

Value:

Type: Pressure (Pa)

Description: Standard pressure drop

rho0

Value:

Type: Density (kg/m³)

Description: Standard medium's density

frictionLoss

Value:

Type: Real

Description: Part of friction losses fed to medium

Components (1)

medium

Type: Medium

Description: Medium in the component

Used in Examples (1)

PumpAndValve

Example: cooling circuit with pump and valve