Simple gearbox with variable efficiency
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| C | |
| in the palette | on the schematic |
The block is designed to simulate a gearbox with a constant gear ratio and friction in bearings and with gear meshing. The block is described by the following formulas:
where:
- sC and sR – turn angles of bodies at ports "C" and "R", respectively, rad
- ωC and ωR – angular speeds at ports "C" and "R", respectively, rad/s
- εC and εR – angular accelerations at ports "C" and "R", respectively, rad/s2
- TC and TR – torques at ports "C" and "R", respectively, Nm
- BB and BF – coefficients of bearing friction on the driving and driven shafts, Nm·s/rad
- U – gear ratio
- dir – value indicating the matching of the directions of rotation of the driving and driven shafts, has a value of 1 or -1
- ν – gearbox efficiency defined through the input port "Nu"
The block allows you to change the direction of the "B" and "F" ports for easy connection to other blocks of the model. If the block has both input ports, then the coupling equation is solved. A detailed description of the simulation approach for the gear ratios is given on the page Simulating transmission.
The gear ratio value U is displayed next to the block.
Inputs
| Name | Description | Connection line type |
|---|---|---|
| Nu | Defined gearbox efficiency | Mathematical |
Ports
| Parameter | Description | Connection line type |
|---|---|---|
| B | Port for connecting the drive shaft (base). The port is input if specified in the "Input Port" property, otherwise this port is output | Rotary mechanics |
| F | Port for connecting the driven shaft (following). The port is input if specified in the "Input Port" property, otherwise this port is output | Rotary mechanics |
Outputs
| Name | Description | Connection line type |
|---|---|---|
| Q | Power losses due to bearing friction and gear meshing (efficiency) | Mathematical |
Properties
| Title | Parameter | Description | By default | Data type |
|---|---|---|---|---|
| Input port | Mod_Type | Allows you to specify the input ports. The possible values are: "B", "F", "B and F" | B and F | Перечисление |
| Time constant for solving the nonlinear algebraic equation, s | Tau | The time constant for solving the nonlinear algebraic equation. Used to solve the coupling equation. The property is available when selecting the input ports " B and F" | 0.1 | Вещественное |
| Kinematics | A group of properties that set the kinematic parameters of the rotary motion | |||
| Gear ratio (Wb/Wf) | U | Gear ratio | 2 | Вещественное |
| Direction of rotation of the driving and driven shafts | Dir | Allows you to set the direction of rotation of the driving and driven shafts. The possible values are: "Same direction", "Opposite direction" | In the same direction | Перечисление |
| Losses | A group of properties that define loss parameters | |||
| Coefficient of the driving shaft bearing friction, Nm·s/rad | B_B | Coefficient of the driving shaft bearing friction | 0 | Вещественное |
| Coefficient of the driven shaft bearing friction, Nm·s/rad | B_F | Coefficient of the driven shaft bearing friction | 0 | Вещественное |
| Power threshold, W | Q_th | The value of the power transmitted through the gearbox, below which the efficiency is increased to achieve the stability of the numerical solution | 0.1 | Вещественное |
| Minimum efficiency | Nu_min | Minimum efficiency factor | 0.01 | Вещественное |
Parameters
| Name | Parameter | Description | Data type |
|---|---|---|---|
| Power losses, W | Q | Power losses due to bearing friction and gear meshing (efficiency) | Вещественное |
| Driving shaft | A group of parameters displaying the parameters of the driving shaft | ||
| Angular speed, rad/s | Wb | Angular speed value at the port "B" | Вещественное |
| Torque, Nm | Tb | Torque transmitted from the driving shaft to the gearbox | Вещественное |
| Power, W | Qb | Power transmitted from the driving shaft to the gearbox | Вещественное |
| Driven shaft | A group of parameters displaying the parameters of the driven shaft | ||
| Angular speed, rad/s | Wf | Angular speed value at the port "F" | Вещественное |
| Torque, Nm | Tf | Torque transmitted from the gearbox to the driven shaft | Вещественное |
| Power, W | Qf | Power transmitted from the gearbox to the driven shaft | Вещественное |
Examples
Examples of block application: