I'm trying to simulate a load-lock for a semi-conductor type application. I have a boat full of very thin wafers that will enter a small chamber which will then be purged with Nitrogen to remove the Oxygen content before the boat is moved into the main process chamber. I'm running a time-dependent simulation to figure out how long it will take for the Oxygen in the small chamber to reach a certain ppm. I'm fine with the mass fraction analysis part of it, but what I'm having trouble with is setting up a mesh that will solve in a reasonable amount of time. My first attempt, I had a fairly loose mesh for the majority of the chamber, and a local initial mesh around the boat full of wafers with narrow channel refinement selected, but it ran overnight and didn't even finish the mesh calculation! Any ideas?
Thanks in advance for any insights you can provide.
sounds like you may have cranked up the mesh too far
how many cells were in the coarse mesh solution?
what values did you change for the next one? how many cells did it end up generating
what i'd suggest doing is checking the "manual" settings behind the automatic settings. make sure one parameter or another isn't increasing significantly causing too many cells and move slowly upwards in mesh refinement.
the next part you'll probably have to deal with is having the time dependent study run in a reasonable time. start with a coarse manual mesh setting and then a smaller manual time step that captures the overall behavior and then you can go to automatic time stepping.
overall this assumes you've done everything you can to simplify the analysis (simplify components, remove components that aren't important, leverage symmetry..etc) and that there aren't any modeling problems/errors (like invalid contacts).