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July 8, 2013, 09:35 |
Eulerian VOF method-outlet boundary?????
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#1 |
Member
sajeesh
Join Date: Feb 2013
Posts: 52
Rep Power: 13 |
Hi
I am doing a 2D simulation for the movement of a water droplet having Diameter 25 micrometer through a channel of cross scetion 50 micro X 500 micro.. Using Eulerian VOF coupled method to explicitly define the velocity of droplet and oil phase I patch the droplet phase and assign a volume fraction of 1 to that water droplet patched region I am using transient case with double precision Oil as primary phase and secondary phase as droplet scheme: phase coupled SIMPLE gradient : Least sqaure method Momentum : first order upwind volume fraction: geo construct Inlet BC: velocity for oil and droplet volume fraction zero and droplet velocity also at inlet when i am using Outlet boundary condition I have to define the back flow volume fraction. initially If i give the back flow fraction as 0 the simulation running fine and give the correct tracking of interface also For me i want to eject the droplet from the exit.But by this condition after the simulation the droplet is stuck at exit.solution gets stopped by the high courant number Similarly i tried with outflow BC.at that time also simulation perfect upto reaching the outlet then again the simulation stopped and the droplet is not going out. When i tried outlet boundary condition with back flow volume fraction of droplet as 1 it is showing error ->Solution diverging ..velocity diverging .Global courant number more than 250.. Please help me to eject the droplet from the channel during simulation.For that what BC should i give at outlet... My email ID sajeeshperil@gmail.com Thanking You sajeesh |
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July 10, 2013, 04:34 |
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#2 |
New Member
Join Date: Jul 2013
Posts: 12
Rep Power: 12 |
Hello,
I am also working on similar Project on wetting Dynamics of an indium droplet. Can you send me your files, so that I can recommend something mehmet.yigit.balta@gmail.com |
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July 10, 2013, 08:25 |
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#3 |
Member
sajeesh
Join Date: Feb 2013
Posts: 52
Rep Power: 13 |
sir what files you want....
case and data file |
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July 10, 2013, 09:26 |
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#4 |
New Member
Join Date: Jul 2013
Posts: 12
Rep Power: 12 |
yes please send me case and last data file so that i can look through
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September 23, 2013, 01:38 |
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#5 |
Member
sajeesh
Join Date: Feb 2013
Posts: 52
Rep Power: 13 |
sir
did you get my mail..have seen the files....pls reply me..if you got it Sajeesh |
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September 23, 2013, 01:59 |
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#6 |
Member
sajeesh
Join Date: Feb 2013
Posts: 52
Rep Power: 13 |
sir
did you get my mail..have seen the files....pls reply me..if you got it Sajeesh |
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September 26, 2013, 03:34 |
droplet
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#7 |
New Member
Join Date: Jul 2013
Posts: 12
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Hi saajesh:
I think you should try like this: 1 Finer mesh VOF method instead of Euler Implicit instead of explicit Servers: Pressure based Coupled Least square cell based Quick Quick Small time steps (like 1e-6) My droplet and tank project with wall adhesion worked like this Sorry for the late answer, Good luck! |
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September 26, 2013, 09:39 |
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#8 |
Member
sajeesh
Join Date: Feb 2013
Posts: 52
Rep Power: 13 |
Thanks sir for reply
How i can give velocity for the droplet if i select the VOF model I want to give different velocity for the droplet. To study the internal external velocity vectors at differnt flow rates of discrete phase Sajeesh |
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