Hi,
When using multi cavity analysis we found imbalance in filling with following cases
attached the pictures for reference. Looking for your comments on the elements type for Part and feed for multi cavity considering 3D.
Version used 2015
Thanks in advance.
Regards,
Rajesh PV
I am sure you might be expecting similar end of fill regions in all the options but visually all are different.
Case 1-Full 3D directly meshed all surfaces-
Case 2- Single cavity meshed and rotated to replicate
Both Case -1 and 2 are correct. Even thought Geometrically balanced, there may shear induced imbalance. Actually result may be as actual.
refer below shown example, high sheared material will be hotter compared to low sheared material.
Full 3D will capture development of Non Homogeneous melt conditions. Some cavity receives hotter material & other may receive colder material.
Case 3- Part 3D & Feed Beam elements.
This option shows, similar temperature, pressure in all the cavities but not as actual
Case 4-Full 3D Direct cone eliminating sprue
it is not advisable option, can be used during initial iterations.
Case 5- Part,Runner & gate 3D, Sprue- Beam elements
This option also can be used, but your results shows, there is shoot up in pressure due to imbalance in results.
Case 1, 2, 3, 5, you can expect similar results, but need to care in meshing of gates,Gate region &
there must be clear boundary between gate and part also finer mesh around gate.
(refer below Tips provided by Autodesk), which may be helpful to you.
TIPS 2:
Hello Madhu,
With full 3D gate multicavity runner systems we are facing this problem many times, even though we couldn't find any impact in melt internal behaviour due to shear heating (Shear induced flow), we could see perfect concentric flow with homogeneous melt conditions still the flow imbalance is coming. Do we need to change the runner design in that case if flow imbalance happening not due to non-homogeneous melt conditions..?
Dear Madhu,
Thanks for the detailed information.However there is huge variations observed with these types of mesh variation. Also the 3D repair wizard creates variation across cavities which can also induce variation. Was much interested in looking for some advice to over come during the mesh wizard.
Thanks again for providing the information which is greatly useful.
Regards,
Rajesh PV
Hi Rajesh
what is the number of layers through thickness, you have kept while converting to 3D.
if you have 6 layers across thickness, please try same set of analysis with 8 or 10 layers and share the results.
Thanks
Pradeep kumar
Hi Pradeep,
This mesh was used with 8 layers across thickness.
Regards,
Rajesh PV