Release 11.0 Documentation for ANSYS Workbench
A spring is an elastic element that regains its original shape after being compressed or extended. Springs are defined as “unloaded”, that is, tension or compression loading conditions are not included in the definition of a spring. Expressed another way, a spring’s free length is the length of the spring as defined. If a spring is changed due to a Configure action of a joint attached to a spring, the spring’s free length is automatically updated to the new length of the spring. In effect, the spring before the Configure action is replaced by a new spring with a new free length after the Configure action. This happens for springs that are associative to geometry and the geometry changes location in space.
You can define a longitudinal spring to connect two bodies together or to connect a body to ground. A longitudinal spring generates a force which depends on a linear displacement of an element. For a flexible dynamic analysis or rigid dynamic analysis, you can use a longitudinal spring as a damping force, which is a function of velocity.
You can scope a spring to single or multiple faces, single or multiple edges, or to a single vertex. The scoping can either be from body-to-body or body-to-ground. For body-to-body scoping, there is a reference and mobile side. For body-to-ground scoping, the reference side is assumed to be grounded (fixed); scoping is only available on the mobile side. In addition to setting the scoping (where the spring attaches to the body), you can set the spring location on both the mobile and reference side. Since this is a unidirectional spring, these 2 locations determines the spring’s line of action. As such the spring reference and mobile location cannot be the same as this would result in a spring with zero length.
Springs include Pinball Region and Behavior as advanced properties.
Use the Pinball Region to define where the spring attaches to face(s), edge(s), or a single vertex if the default location is not desirable. By default, the entire face/edge/vertex is tied to the spring element. This may not be desirable, warranting the input of a Pinball Region setting, for the following reasons:
If the scoping is to a topology with a large number of nodes, this can lead to an inefficient solution in terms of memory and speed.
Overlap between the spring scoped faces and other displacement type boundary conditions can lead to over constraint and thus solver failures.
Use the Behavior property to specify scoped geometry as either Rigid or Deformable. Refer to the Geometry Behavior section for more information.
A Spring is classified as a remote boundary condition. Refer to the Remote Boundary Conditions section for a listing of all remote boundary conditions and their characteristics.
Several outputs are available via a spring probe.
To add a spring:
After importing the model, highlight the Model object in the tree and choose the Connections button from the toolbar.
Highlight the new Connections object and choose either Body-Ground> Spring or Body-Body> Spring from the toolbar, as applicable.
Highlight the new Spring object and enter information in the Details View. Note that Longitudinal Damping is applicable only to transient analyses.
This example shows the effect of a longitudinal spring connecting a rectangular bar to ground to represent a damper. A flexible dynamic analysis was performed in the environment shown:
The following are the Details View settings of the Spring object:
Presented below is the Total Deformation result:
The following demo is presented as an animated GIF. Please view online if you are reading the PDF version of the help. Interface names and other components shown in the demo may differ from those in the released product.
