Torsion damper

Linear rotational damper: τ = d·ω_rel.

  • rotational
  • Modelica Standard Library
  • 2 ports
  • 1 parameter
BlockTorsion damperKindrotDamperLibraryRotational

Description

A linear viscous damper between two flanges: the torque is proportional to the relative speed. Connect it to Fixed (rotational) for friction to the housing.

Example

Rotational drivetrain A torque step drives a motor inertia through a 2:1 gear and a shaft spring into a damped load, with every rotational sensor.

Torque 1 N·mMotor 0.01 kg·m²Gear 2:1Shaft powerShaft torqueShaft 1000 N·m/radLoad 0.04 kg·m²Friction 0.1FrameMotor accelerationShaft twist rateLoad speed
In Gradara, select a Torsion damper block and press F1, then choose Open example. It opens as a new model in My models, ready to run.

Also in this example:Torque sensorFixed (rotational)Torsion springInertia (ideal)Ideal gearTorque stepSpeed sensor (ideal)Acceleration sensorPower sensor (rotational)Relative speed sensor

Ports

Conserving terminals 2

  • aflange_arotational

    Flange a. Receives −τ.

  • bflange_brotational

    Flange b. Receives τ, the damping torque.

Parameters

  • Dampingd1 N·m·s/rad

    ≥ 0

    Damping coefficient, in N·m·s/rad. Zero or positive.

Equations

Modelica
ω_rel = d(flange_b.phi − flange_a.phi)/dt
τ = d · ω_rel
flange_b.tau = τ, flange_a.tau = −τ

Implementation

Modelica Standard Library 4.1.0Modelica.Mechanics.Rotational.Components.Damper
MSL documentation

Assumptions and limitations

  • Purely viscous: no Coulomb friction or stiction.

See also

Select a block in Gradara and press F1 to open its page offline.