Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
convergency problem with the introdution of gravity in 2D modeling
Posted Jul 5, 2010, 2:39 p.m. EDT 0 Replies
Please login with a confirmed email address before reporting spam
I'm modeling a CVD growth in a quartz tube furnace using chemical engineering model (chns+chcd). When there is no gravity considered, calculation converged easily.
When gravity was introduced as volume force in y-direction, I still could manage to solve it for chns only by increasing gravity from 9 = 0.1m/s^2 to 9 = 9.81m/s^2 gradually. However, when I want to include chcd in the solver, the results did not converge.
The geometry of the furnace is: tube with diameter of 2.5" and length of 45", both inlet and outlet have a diameter of 0.25". The growth wafer in the furnace is roughly 1cm^2. I did notice the size difference is huge and I used boundary layer mesh on the wafer surface to investigate the adjacent area.
To play around, instead a quarter inch inlet, I set the whole 2.5" diameter of the tube as inlet and the same for outlet. This time I can solve chns+chcd with gravity introduced but just up to g = 1m/s^2.
I have no clue what's going wrong and will highly appreciate any inputs.
Thanks and regards,
Zhong
Hello Zhong Li
Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.
If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.