Polymer Melt Simu with Abaqus

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Polymer Melt Simu with Abaqus

Daniel Köhler
Hello,

I’m trying to simulate with Abaqus CEL the impact of the polymer melt on an
insert (a wire) in an injection molding cavity. A major problem is to model
the polymer melt material behaviour like temperature und and shear rate
dependent viscosity (Cross-Arrhenius in a VUVISCOSITY Sub) and the
pvT-behaviour (2domain Tait in a VUEOS Sub). Especially the pvt behaviour is
difficult. Abaqus expects a formula for the pressure, so I converted the
tait equation for pressure ignoring v_1 and wrote it into the VUEOS
subroutine that I have attached.
Currently abaqus calculates a negative pressure at the first elements to be
filled and quits the simulation with an error due to excessive distortion of
elements. It seems like abaqus assigns a temperature to elements that are
being filled which is lower than the actual melt temperature leading to a
negative pressure. This could be because the nodes that are not filled yet
are not assigned a temperature, so they appear with zero Kelvin. I want
Abaqus to ignore this temperature as the elements belonging to these nodes
are not filled.



I added the current input, odb and the tait subroutine file.

I would be very grateful, if someone out there could help me with this
issue.



Kind regards,

Daniel



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Re: Polymer Melt Simu with Abaqus

Daniel Köhler
I realized that abaqus doesn't allow attachments. That's why I uploaded the files here:
 https://we.tl/t-SlR5csAkk4 https://we.tl/t-SlR5csAkk4

I especially wonder whether I'm supposed to calculate the pressure in VUEOS with densityNew or densityMEAN and with tempOld or tempNew?
 Am I supposed to give empty elements an initial temperature?
 

 Regards
 Daniel