Loss Element

Loss Element component

The Loss Element component models losses using velocity-dependent efficiency.

Kinematic Equation

Where ${\mathrm{ϕ}}_{\mathrm{fa}}$  and ${\mathrm{\varphi }}_{\mathrm{fb}}$ are the absolute rotation angles of ${\mathrm{flange}}_{a}$ and ${\mathrm{flange}}_{b}$, respectively and $▵\mathrm{\varphi }$ is the fixed rotation angles of ${\mathrm{flange}}_{b}$ with respect to ${\mathrm{flange}}_{b}.$

Also ${\mathrm{\varphi }}_{a}$ and ${\mathrm{\varphi }}_{b}$ are defined as:

,   $x$ ∈ $\left\{a,b\right\}$

Torque Balance Equation (No Inertia)

Where and ${\mathrm{\tau }}_{b}$ are the torques applied to ${\mathrm{flange}}_{a}$ and ${\mathrm{flange}}_{b}$, respectively.

Also   ${\mathrm{\tau }}_{\mathrm{loss}}$ is the loss torque and is defined as:

Where

${\mathrm{\omega }}_{a}$ =

Power Loss:

When the gear is non-ideal (ideal = false ), the power loss (${P}_{\mathrm{loss}}$) is calculated as:

Connections

 Name Condition Description ID ${\mathrm{flange}}_{a}$ - Flange to driver shaft flange_a ${\mathrm{flange}}_{b}$ - Flange to driven shaft flange_b support Support $\mathrm{ideal}=\mathbf{false}$ Conditional real output port for power loss lossPower

Parameters

Symbol

Condition

Default

Units

Description

ID

$\mathrm{ideal}$

-

$\mathbf{false}$

-

Defines whether the component is:

true - ideal or

false - non-ideal

ideal

-

$0$

$\left[\mathrm{rad}\right]$

Defines fixed rotation of ${\mathrm{flange}}_{b}$ with respect to ${\mathrm{flange}}_{a}$

deltaPhi

data source

$\mathrm{ideal}=\mathbf{false}$

GUI

-

Defines the source for the loss data:

 • entered via GUI [GUI]
 • by an attachment [attachment]
 • by an external file [file]

datasourcemode

Use support

-

$\mathbf{false}$

-

Enables/disables the support flange

useSupport

$\mathrm{η}\left({\mathrm{ω}}_{a}\right)$

data source = GUI

$\left[0,1,1\right]$

$\left[\frac{\mathrm{rad}}{s},-,-\right]$

Defines velocity dependant efficiency

The columns are:

[${\mathrm{\omega }}_{a}$     (${\mathrm{\eta }}_{1}$ (${\mathrm{\omega }}_{a}$ )     ${\mathrm{\eta }}_{2}$ (${\mathrm{\omega }}_{a}$ )]

Five options are available:

 • 1 by 1 array: entered value is taken as the constant efficiency for forward and backward cases

${\mathrm{\eta }}_{1}$ (${\mathrm{\omega }}_{a}$ ) = ${\mathrm{\eta }}_{2}$ (${\mathrm{\omega }}_{a}$ ) = ${\mathrm{\eta }}_{}$

 • 1 by 2 array: first entered value is taken as the constant efficiency for forward case and the second for backward cases

${\mathrm{\eta }}_{1}$ (${\mathrm{\omega }}_{a}$ ) = (${\mathrm{\omega }}_{a}$ ) = ${\mathrm{\eta }}_{2}$

 • 1 by 3 array: first column is ignored and the second and third values are taken as constant efficiencies for forward and backward cases, respectively
 • n by 2 array: 2nd column is efficiency

$\mathrm{η}$ (${\mathrm{\omega }}_{a}$ ) = ${\mathrm{\eta }}_{1}$ (${\mathrm{\omega }}_{a}$ ) = ${\mathrm{\eta }}_{2}$(${\mathrm{\omega }}_{a}$ )

 • n by 3 array:

2nd column is forward efficiency

${\mathrm{\eta }}_{1}$  (${\mathrm{\omega }}_{a}$ )

3rd column is backward efficiency

${\mathrm{\eta }}_{2}$  (${\mathrm{\omega }}_{a}$ )

Note: The rows of the array are ordered according to ${\mathrm{\omega }}_{a}$, with the first row having the smallest |${\mathrm{\omega }}_{a}$|

lossTable

data source = attachment

-

Defines velocity dependant  efficiency

First column is angular velocity (${\mathrm{\omega }}_{a}$ )

(See $\left[\mathrm{η}\right]$ below)

data

data source = file

-

fileName

$\left[\mathrm{η}\right]$

data source = attachment or file

$\left[2,3\right]$

-

Defines the corresponding data columns used for forward efficiency (${\mathrm{\eta }}_{1}$) and backward efficiency (${\mathrm{\eta }}_{2}$ )

Two options are available:

 • 1 by 1 array:

Data column corresponding to the column number is used for both forward and backward efficiency

 • 1 by 2 array:

Data column corresponding to the first column number is used for forward efficiency (

and data column corresponding to the second column number is used for backward efficiency (

columns

smoothness

$\mathrm{ideal}=\mathbf{false}$

Table points are linearly interpolated

-

Defines the smoothness of table interpolation. There are two options:

 • Table points are linearly interpolated
 • Table points are interpolated such that the first derivative is continuous

smoothness