WOLFRAM SYSTEM MODELER

# LossyGearDemo2

Example to show combination of LossyGear and BearingFriction

# Wolfram Language

In[1]:=
`SystemModel["Modelica.Mechanics.Rotational.Examples.LossyGearDemo2"]`
Out[1]:=

# Information

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

This model contains bearing friction and gear friction (= efficiency). If both friction models are stuck, there is no unique solution. Still a reliable Modelica simulator should be able to handle this situation.

Simulate for about 0.5 seconds. The friction elements are in all modes (forward and backward rolling, as well as stuck).

You may plot:

```Inertia1.w,
Inertia2.w          : angular velocities of inertias
powerLoss           : power lost in the gear
bearingFriction.mode:  1 = forward rolling
0 = stuck (w=0)
-1 = backward rolling
gear.mode           :  1 = forward rolling
0 = stuck (w=0)
-1 = backward rolling
```

Note, `powerLoss` (= sum of the power flows of the connectors) and `gear.powerLoss` (= `gear.tau_loss`*`gear.w_a`, where `gear.tau_loss` is determined in a non-trivial way from the stuck/sliding situation of the bearing and teeth friction; = equation (16) in [Pelchen2002]) should be identical, or the difference should be close to zero, if model LossyGear is correctly implemented.

Note: This combination of LossyGear and BearingFriction is not recommended to use, as component LossyGear includes the functionality of component BearingFriction (only peak not supported).

# Components (9)

gear Type: LossyGear Description: Gear with mesh efficiency and bearing friction (stuck/rolling possible) Type: Inertia Description: 1D-rotational component with inertia Type: Inertia Description: 1D-rotational component with inertia Type: Torque Description: Input signal acting as external torque on a flange Type: Torque Description: Input signal acting as external torque on a flange Type: Sine Description: Generate sine signal Type: Ramp Description: Generate ramp signal Type: BearingFriction Description: Coulomb friction in bearings Type: Fixed Description: Flange fixed in housing at a given angle