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Model cannot proceed at all after switching to force load

Model cannot proceed at all after switching to force load

Model cannot proceed at all after switching to force load

(OP)
Hi all,



I have a very small model that runs perfectly under displacement loads. However, when I switched to force loads, the model cannot even move one step at all. Would you please help me with this?



Thanks!

Attachment: the inp file
https://copy.com/8mpoUT8BtjfS

Figure 1. The model runs smoothly under displacement load


Figure 2. The force exceeds 1 newton under displacement load, therefore my load is not too high

RE: Model cannot proceed at all after switching to force load

It's because of the contact condition you have. First impose a dummy displacement to push the parts together, then deactivate that displacement and apply your load.

RE: Model cannot proceed at all after switching to force load

(OP)
Hi corus,

Oh man thank you sooo much! It is so obvious but I didn't think of it. I realized that the numerical singularity is coming from the contact (from the .msg file, the solver does not realize the contact at all). I tried to add a small force to push it into contact but it didn't work (still singular). This is so obvious but I did not think of it until you mentioned... Thanks a lot man!

It now worked perfectly.

-Shawn

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