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David October 21, 2005 04:35

Path Line in a injection molding
 
Hi, I simulate a injection molding die with usual polymer.

I've done a lot of iteration and for the last 10000 steps the residuals values remains constant. But when I show the path lines, with step size 10mm; steps 20000, this message appears:number tracked = 204; escaped = 190; incomplete = 14.

What's wrong? The mesh, the iterations numbers or something else?

Is it also possible to increase the lines number?

Thank you for the answer. David

David October 27, 2005 03:45

Re: Path Line in a injection molding
 
Hi The main problem is the incomplete number!

Is the mesh wrong ?

Thanks! David

Henrik Ström October 27, 2005 05:34

Re: Path Line in a injection molding
 
Hello!

If I am not mistaken, this just means that you have to increase the number of steps in order to make all path lines complete (that is, make them escape the domain). The total lenght travelled by a path line is the step size times the number of steps, and probably some path lines need to travel a longer way in your domain. So just try increasing the number of steps, and that would probably decrease the number of "incomplete" paths. (That is, unless you have paths that are "trapped" and will never leave the domain but stay in a recirculating region).

/Henrik

David November 4, 2005 08:55

Re: Path Line in a injection molding
 
Hello,

Thank you for your answer.

I've try to increase the number of steps (500'000 steps) but nothing change.

I've also try to adapt the grid without success.

Now i've remesh the model and now i'm running the iterations.

Somebody have other advices ??

I've no more ideas.

Thank you

David

Henrik Ström November 4, 2005 10:24

Re: Path Line in a injection molding
 
How long is the way the path lines should travel through your domain? Make sure step size times steps is more than this. Also, you should try to zoom in when displaying the path lines to see where they end. Incomplete path lines do not exit through any "escape" boundary but stop inside the domain. Try reducing the number of pathlines if it is difficult to see.

Hope this helps!

/Henrik

David November 10, 2005 06:07

Re: Path Line in a injection molding
 
Thank you for your advices, Henrik.

I'm sure that the path lines have enough time to travel through my domain. I can clearly show the incomplete path line. They don't escape the domain because they are "blocked" into some cells or someting like this. The path lines travel into the cells.

I'm trying to refine the mesh but the problem is always here.

David

David November 10, 2005 08:34

Re: Path Line in a injection molding
 
Thank you for your advices, Henrik.

I'm sure that the path lines have enough time to travel through my domain. I can clearly show the incomplete path line. They don't escape the domain because they are "blocked" into some cells or someting like this. The path lines travel into the cells.

I'm trying to refine the mesh but the problem is always here.

David

srinivas November 15, 2005 07:35

Re: Path Line in a injection molding
 
hi

i am working with the similar kind of problem.try this your maximam no of steps should be the product of your no of cell elements and step length factor.

hope it"ll works

kike September 2, 2011 10:08

So, did you get to solve your problem? Unfortunately I have the same problem of incomplete paths. I even decided to increase the step size to 10cm and the number of steps to 5000 with no much change (except that it takes a long time to display pretty much the same geom). In the most exagerated case one pathline changed to escaped from 9 (i do path skips to reduce display time). The total geometry area is about 40*5 Any help would be greatly appreciated.


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