Explicit Displacement B.C. after anneal step

[ryankb]

I'm running a nitinol explicit simulation using displacement B.C.'s to do the heat setting procedure. I'm doing a multi-step process, so I have an anneal step in the middle. This is causing me difficulties with my B.C.'s however. Say I want to displace by 2mm. In the B.C. definition, for Step1, I set it to 1mm, and Step2 I put it to 2. In Abaqus Standard simulations, the 2mm is absolute displacement to the original time point, so I would only see a total of 2mm displacement. In Explicit, however, I'm seeing the 2mm is relative to the first (sometimes). So, logically, I then need to set both Step1 and Step2 displacements to 1mm in order to achieve the total 2mm displacement. However, when I do that, it moves 1mm during Step1, and doesn't move at all during Step2.

What's going on? I'd be OK with this being consistent, but something seems to be toggling it between absolute and relative displacements and I don't see where this is happening.

 

[IceBreakerSours]

Check your *Amplitude definition.

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[Mustaine3]

I'm sure the cause is the default amplitude, that is used when nothing else is defined. Think about the effect that this amplitude has in each step with an applied displacement. Also check the .sta or .msg file for warnings regarding displacement jumps.

 

[ryankb]

The amplitude definition is correct - that was one of the first things I checked. I do have a displacement jump warning - but I have multiple steps with displacements and I assumed this was what it was from. I'll look more at that warning and what it's about.