Polymer Melt Simu with Abaqus

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Polymer Melt Simu with Abaqus

Daniel Köhler

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

Kind regards,


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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?