modelSpringDamperSeries
Linear spring and linear damper in series connection
Extends from Interfaces.PartialLineForce (Base model for massless line force elements), Modelica.Thermal.HeatTransfer.Interfaces.PartialElementaryConditionalHeatPort (Partial model to include a conditional HeatPort in order to dissipate losses, used for textual modeling, i.e., for elementary models).
Information
Linear spring and linear damper in series connection acting as line force between frame_a and frame_b:
frame_a --> damper ----> spring --> frame_b
| |
|-- s_damper --| (s_damper is the state variable of this system)
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 equations:
f = c*(s - s_unstretched - s_damper); f = d*der(s_damper);
where "c", "s_unstretched" and "d" are parameters, "s" is the distance between the origin of frame_a and the origin of frame_b. "s_damper" is the length of the damper (= an internal state of this force element) and der(s_damper) is the time derivative of s_damper.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | animation | true | = true, if animation shall be enabled |
| SI.TranslationalSpringConstant | c | Spring constant | |
| SI.Length | s_unstretched | 0 | Unstretched spring length |
| SI.TranslationalDampingConstant | d | 0 | Damping constant |
| SI.Length | s_damper_start | 0 | Initial length of damper |
| Boolean | useHeatPort (from PartialElementaryConditionalHeatPort) | false | = true, if heatPort is enabled |
| SI.Temperature | T (from PartialElementaryConditionalHeatPort) | 293.15 | Fixed device temperature if useHeatPort = false |
| Animation › if animation = true | |||
| SI.Distance | length_a | world.defaultForceLength | Length of damper cylinder at frame_a side |
| Integer | numberOfWindings | 5 | Number of spring windings |
| Advanced | |||
| SI.Distance | s_small (from LineForceBase) | 1e-10 | Prevent zero-division if distance between frame_a and frame_b is zero |
| Advanced › If enabled, can give wrong results, see MultiBody.UsersGuide.Tutorial.ConnectionOfLineForces | |||
| Boolean | fixedRotationAtFrame_a (from LineForceBase) | false | = true, if rotation frame_a.R is fixed (to directly connect line forces) |
| Boolean | fixedRotationAtFrame_b (from LineForceBase) | false | = true, if rotation frame_b.R is fixed (to directly connect line forces) |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Interfaces.Frame_a | frame_a (from PartialTwoFrames) | Coordinate system a fixed to the component with one cut-force and cut-torque | |
| Interfaces.Frame_b | frame_b (from PartialTwoFrames) | Coordinate system b fixed to the component with one cut-force and cut-torque | |
| HeatTransfer.Interfaces.HeatPort_a | heatPort (from PartialElementaryConditionalHeatPort) | Optional port to which dissipated losses are transported in form of heat |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| SI.Position | s_damper | Actual length of damper (frame_a - damper - spring - frame_b) | |
| SI.Diameter | diameter_a | world.defaultForceWidth | Diameter of damper cylinder at frame_a side |
| SI.Diameter | diameter_b | 0.6*diameter_a | Diameter of damper cylinder at damper-spring side |
| Types.Color | color_a | {100, 100, 100} | Color of damper cylinder at frame_a |
| Types.Color | color_b | {155, 155, 155} | Color of damper cylinder at damper-spring frame |
| Types.SpecularCoefficient | specularCoefficient | world.defaultSpecularCoefficient | Reflection of ambient light (= 0: light is completely absorbed) |
| SI.Distance | width | world.defaultForceWidth | Width of spring |
| SI.Distance | coilWidth | width/10 | Width of spring coil |
| Types.Color | color | Modelica.Mechanics.MultiBody.Types.Defaults.SpringColor | Color of spring |
| SI.Distance | length (from LineForceBase) | Distance between the origin of frame_a and the origin of frame_b | |
| SI.Position | s (from LineForceBase) | (Guarded) distance between the origin of frame_a and the origin of frame_b (>= s_small)) | |
| SI.Position[3] | r_rel_0 (from LineForceBase) | Position vector from frame_a to frame_b resolved in world frame | |
| Real[3] | e_rel_0 (from LineForceBase) | Unit vector in direction from frame_a to frame_b, resolved in world frame | |
| SI.Position[3] | r_rel_a (from PartialLineForce) | Position vector from origin of frame_a to origin of frame_b, resolved in frame_a | |
| Real[3] | e_a (from PartialLineForce) | Unit vector on the line connecting the origin of frame_a with the origin of frame_b resolved in frame_a (directed from frame_a to frame_b) | |
| SI.Force | f (from PartialLineForce) | Line force acting on frame_a and on frame_b (positive, if acting on frame_b and directed from frame_a to frame_b) | |
| SI.Power | lossPower (from PartialElementaryConditionalHeatPort) | Loss power leaving component via heatPort (> 0, if heat is flowing out of component) | |
| SI.Temperature | TheatPort (from PartialElementaryConditionalHeatPort) | Temperature of heatPort |