CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > FLUENT

What viscosity to use for solid phase in VOF model

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   June 14, 2017, 18:09
Default What viscosity to use for solid phase in VOF model
  #1
New Member
 
RJC
Join Date: Jun 2015
Posts: 18
Rep Power: 11
redwanamit034 is on a distinguished road
Hello,

I am modeling a melting problem with a VOF model.
The purpose of the simulation is to get the temperature distribution as well as the flow and shape of the molten metal (Copper).

The initial temperature for the model is room temperature, so the metal is in solid phase and then very high heat flux is added to melt the metal. The metal is supposed to melt in less than 1 sec.

I turned on VOF, gravity, Solidification/melting and energy model in fluent. The model runs and converges. But the problem is that the metal starts to flow even before it melts.

To add the solidus & liquidus temperature and solvent melting heat in the material property, I had to use "FLUID" material type. There properties cannot be specified for Solid material in Fluent (or is there any way?). For the viscosity, I used the viscosity of liquid metal (around 0.004 Pas). But if I use a piecewise linear function to define high viscosity for the initial solid phase, the model diverges after a few iterations and reports that "velocity is diverging and courant number is greater than 250. Use shorter time step". I reduced the time step to 1e-5, and also reduced URF. But the same thing happens. But when I use a constant low viscosity of 0.004 pas, model works. But as I said, in that case the metal starts to flow even before it starts to melt.

Any suggestion?
redwanamit034 is offline   Reply With Quote

Reply

Tags
melting, viscosity, vof model


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Patching Second Phase Region in Fluent V13 VOF Model sda FLUENT 19 July 3, 2022 07:00
VOF plus Solidification/melting model kql FLUENT 3 April 29, 2014 17:50
Extract primary phase thread in VOF with 3 phases Eric FLUENT 2 July 7, 2011 03:22
Questions about Cross-Arrhenius and Cross-WLF viscosity model awacs OpenFOAM Running, Solving & CFD 4 August 13, 2009 07:56
urgent query regarding vof model plz rply Garima Chaudhary FLUENT 0 July 13, 2007 03:20


All times are GMT -4. The time now is 12:59.