Cylinder

Simple model of a piston in a cylinder

Information

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

This is a simple model of a piston in a cylinder:

The translational flange is connected to the piston, the cylinder has a flowPort at the bottom.

The position of the piston within the cylinder goes from 0 at the bottom to L (length of the cylinder) at the top of the cylinder. If the piston leaves the cylinder, an assertion is triggered.

  • A movement of the piston is coupled with volume flow through the flowPort.
  • The force at the piston is equal to pressure of the fluid times A (cross section of the piston).

The piston is considered without mass.

Note: Take care of the initial conditions. The position of the piston (relative to the support) should be in the range (0, L). The position of the flange (as well as of the support, if useSupport=true) is influenced by connected components.

Parameters (6)

medium

Value: Modelica.Thermal.FluidHeatFlow.Media.Medium()

Type: Medium

Description: Medium

T0

Value:

Type: Temperature (K)

Description: Initial temperature of medium

T0fixed

Value: false

Type: Boolean

Description: Initial temperature guess value or fixed

useSupport

Value: false

Type: Boolean

Description: = true, if support flange enabled, otherwise implicitly grounded

A

Value:

Type: Area (m²)

Description: Cross section of cylinder/piston

L

Value:

Type: Length (m)

Description: Length of cylinder

Outputs (2)

T_port

Type: Temperature (K)

Description: Temperature at flowPort_a

T

Type: Temperature (K)

Description: Outlet temperature of medium

Connectors (3)

flowPort

Type: FlowPort_a

flange

Type: Flange_b

Description: Flange of component

support

Type: Support

Description: Support/housing of component

Components (1)

medium

Type: Medium

Description: Medium

Used in Examples (1)

TestCylinder

Modelica.Thermal.FluidHeatFlow.Examples

Two cylinder system