|
[Sponsors] |
a big problem when using VOF + melting/solidification model |
|
LinkBack | Thread Tools | Search this Thread | Display Modes |
|
March 13, 2017, 13:04 |
a big problem when using VOF + melting/solidification model
|
#1 |
New Member
Join Date: May 2012
Posts: 5
Rep Power: 14 |
hi, friends, i try to simulate the welding process using VOF + melting/solidification models in FLUENT. it is a simple principle that metal is solid and won't move below solidus temperature.
However, i found the situation was not like that. let's look a simple test case. this is initial state; constant ambient temperature; the whole region is considered as fluid domain. of course the melting/solidification model is used. 001.png after 0.02s 002.png metal material is apparently moving, which is wrong. any one have a idea about what is going on here? is it because the solid is a fake solid in VOF model? |
|
March 13, 2017, 23:44 |
|
#2 |
Senior Member
Lucky
Join Date: Apr 2011
Location: Orlando, FL USA
Posts: 5,683
Rep Power: 66 |
Okay the pics aren't labeled or anything but I'm guessing that blue/red is solid/liquid phases or vice-versa. The phase boundary should move in a melting/solidification problem. How are you sure the stationary solid has been moved versus motion of the phase boundary?
|
|
March 14, 2017, 09:30 |
|
#3 |
New Member
Join Date: May 2012
Posts: 5
Rep Power: 14 |
yes, the red is metal at solid temperature, the blue is air
comparing the tow figures, the interface shape apparently changed. |
|
March 14, 2017, 11:18 |
|
#4 |
Senior Member
Lucky
Join Date: Apr 2011
Location: Orlando, FL USA
Posts: 5,683
Rep Power: 66 |
Yes, the "interface" is the phase boundary. If there is melting/solidification then the phase boundary moves as the amount of solid increases/decreases. Is that not what is happening here?
|
|
March 14, 2017, 11:25 |
|
#5 |
New Member
Join Date: May 2012
Posts: 5
Rep Power: 14 |
Actually, the metal is titanium, the temperature remains constant at 300K. No melting is happening. so the interface is not supposed to change, because it is solid/gas interface in reality.
|
|
March 16, 2017, 10:03 |
|
#6 |
New Member
Join Date: May 2012
Posts: 5
Rep Power: 14 |
i think i've figure out the reason. it is due to surface tension. I forgot set zero value of surface tension when temperature drop to below solidus point.
I'm running a test case to prove this hypothesis. |
|
May 18, 2020, 16:31 |
|
#7 |
New Member
Hossein
Join Date: May 2020
Posts: 1
Rep Power: 0 |
Hi Pancard
I have same problem as you, did you find the solution? If you have foun that, help me please |
|
April 29, 2024, 14:25 |
|
#8 |
New Member
Join Date: Aug 2021
Posts: 1
Rep Power: 0 |
Hi Hossein/Pancard
Facing the same issue.. my solid metal is deforming even before the it reached solidus temperature. Please help. I have tried by taking surface tension as zero below solidus and 1.0 above liquidus temperature still the problem is not solved. |
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Overflow Error in Multiphase Modelling with Two Continuous Fluids | ashtonJ | CFX | 6 | August 11, 2014 14:32 |
problem with solving lagrange reaction cloud | Polli | OpenFOAM Running, Solving & CFD | 0 | April 30, 2014 07:53 |
urgent... multiphase cfd model of packed bed reactor.( VOF MODEL using) | balu@gold6 | FLUENT | 4 | July 26, 2012 10:37 |
A Problem with setting the time step in VOF model | Le | FLUENT | 2 | July 20, 2006 22:00 |
Problem with UDF in VOF model | vijay | FLUENT | 0 | April 18, 2006 01:06 |