Changing the slope of spring in ANSYS Workbench 1

[davidmandis]

Hi All,

I am working on a simulation where I am using a spring in ANSYS Workbench 11.0, and would like to change the slope of the spring when the force in the spring exceeds a certain value. I do not know how to extract the force in the spring. Is there any way I can do this in ANSYS WB 11.0 either interactive or through commands? Or alternately can I enter a force-deflection curve for the spring element in Workbench similar to the real constant for COMBIN39 (nonlinear spring) element in ANSYS Classic?

Thanks,

David

 

[doatis]

Hi David,

This should be fairly easy to do.

To check reaction force:
Right Click on 'Solution' > Insert > Probe > Spring

You can then select which spring you want to look at the reaction forces (including the weak spring reaction force if you don't have those turned off).

To change the spring properties, that will require some APDL.

To change spring properties:
Right Click on the spring you've defined underneath 'Connections' > Insert > Commands

You'll notice in the text window, the material/type/real constant number can be accessed using the variable _sid. So, if you wanted to change the spring type, you would type:

et,_sid,39

This will change the spring to be a COMBIN39 from the default COMBIN14. If you know the proper APDL to define the force curve for the COMBIN39, just enter it into the command line with the appropriate 'R' command using the _secid variable to access the real constant number.

Hope this helps,
Doug

 

[davidmandis]

Hi Doug,
I used the same method you mentioned here but am having a lot of convergence issues. This is the command being inserted under the spring,

et,_sid,COMBIN39,0,0,1,0,,1

r,_sid,0.0, 0.0, 0.001016, 2224, 0.002032, 4448,
rmore, 0.003048, 6672, 0.004064, 8896, 0.00508, 11120,
rmore, 0.006096,13344, 0.076200, 13344,

Trying to figure out where its going wrong.

Thanks,
David