Damper

Linear (velocity dependent) damper

Information

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

Linear damper acting as line force between frame_a and frame_b. A force f is exerted on the origin of frame_b and with opposite sign on the origin of frame_a along the line from the origin of frame_a to the origin of frame_b according to the equation:

f = d*der(s);

where "d" is a parameter, "s" is the distance between the origin of frame_a and the origin of frame_b and der(s) is the time derivative of "s".

In the following figure a typical animation is shown where a mass is hanging on a damper.

Parameters (8)

s_small

Value: 1e-10

Type: Distance (m)

Description: Prevent zero-division if distance between frame_a and frame_b is zero

fixedRotationAtFrame_a

Value: false

Type: Boolean

Description: = true, if rotation frame_a.R is fixed (to directly connect line forces)

fixedRotationAtFrame_b

Value: false

Type: Boolean

Description: = true, if rotation frame_b.R is fixed (to directly connect line forces)

useHeatPort

Value: false

Type: Boolean

Description: = true, if heatPort is enabled

T

Value: 293.15

Type: Temperature (K)

Description: Fixed device temperature if useHeatPort = false

animation

Value: true

Type: Boolean

Description: = true, if animation shall be enabled

d

Value:

Type: TranslationalDampingConstant (N·s/m)

Description: Damping constant

length_a

Value: world.defaultForceLength

Type: Distance (m)

Description: Length of cylinder at frame_a side

Inputs (5)

diameter_a

Default Value: world.defaultForceWidth

Type: Diameter (m)

Description: Diameter of cylinder at frame_a side

diameter_b

Default Value: 0.6 * diameter_a

Type: Diameter (m)

Description: Diameter of cylinder at frame_b side

color_a

Default Value: {100, 100, 100}

Type: Color

Description: Color at frame_a

color_b

Default Value: {155, 155, 155}

Type: Color

Description: Color at frame_b

specularCoefficient

Default Value: world.defaultSpecularCoefficient

Type: SpecularCoefficient

Description: Reflection of ambient light (= 0: light is completely absorbed)

Connectors (3)

frame_a

Type: Frame_a

Description: Coordinate system a fixed to the component with one cut-force and cut-torque

frame_b

Type: Frame_b

Description: Coordinate system b fixed to the component with one cut-force and cut-torque

heatPort

Type: HeatPort_a

Description: Optional port to which dissipated losses are transported in form of heat

Components (3)

world

Type: World

shape_a

Type: Shape

shape_b

Type: Shape

Used in Examples (3)

PendulumWithSpringDamper

Modelica.Mechanics.MultiBody.Examples.Elementary

Simple spring/damper/mass system

SpringDamperSystem

Modelica.Mechanics.MultiBody.Examples.Elementary

Simple spring/damper/mass system

HeatLosses

Modelica.Mechanics.MultiBody.Examples.Elementary

Demonstrate the modeling of heat losses