CFD Online Logo CFD Online URL
Home > Forums > FLUENT

Defining Evaporation - A How To Guide.

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Display Modes
Old   July 25, 2005, 04:59
Default Defining Evaporation - A How To Guide.
Posts: n/a
A search through this forum and the Fluent UDF guide has left me with the idea that modelling evaporation isn't going to be a simple process.

I am seeking to model the evaporation from a free surface specifically to investigate the effect of wind speed on evaporation rate and thus cooling of the vessel. When writing the UDF to define mass/heat transfer at the interface (using VOF model) I'm stuck trying to define the cell/face interface thread - so the gas is being generated through the bulk of the fluid instead of only on the surface. Please inform how evaporation can be handled with a UDF.
  Reply With Quote

Old   July 25, 2005, 09:56
Default Re: Defining Evaporation - A How To Guide.
Posts: n/a
Hi, Owen I want to simulate evaporation like this later this year. Can you tell me the formula of the mass/heat transfer during the evaporation process or just give me some information about the material required? If you like, there is my email address. Thanks a lot!

I will looking for the method on how to chase the interface of water/vapor.If there is any information I will tell you about it.

And now I have an idea about this, maybe it is just an approximation. You can define two source terms for the water and vapor continuation equation and one for energy equation.In the DEFINE macro you can judge the whether a cell is interface cell, if it is a inter face cell return the source if not return 0. How to judge whether the cell is a interface cell? Two process: the first:if(( C_VOF(c,pt[0])*C_VOF(c,pt[1]*..) != 0)/*none of C_VOF(c,pt[i]is zero)*/ the cell is a interface cell; and then in the second process: loop over every face of the cell to judge whether there is an adjacent cell in which the VOF(c1,pt[0])=0(no water in the cell),if so it is an interface cell. I think this could help before you find the proper method of chasing the interface. I am not familiar with the VOF model.

  Reply With Quote


Thread Tools
Display Modes

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 On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Evaporation model in ansys Fluent 12.1 oldisbest Fluent UDF and Scheme Programming 10 June 12, 2017 11:46
Evaporation due to Heat Transport using InterFoam (Correct Implementation?) ovie OpenFOAM 12 December 16, 2011 10:44
Question:Considerations about the evaporation in VOF dokeun FLUENT 10 February 24, 2011 21:47
Fluent 5.5. What the differences with fluent 5.3?? confused FLUENT 2 July 29, 2001 21:58
CFD Books Guide Pre-Release, Help Needed David & Jonas Main CFD Forum 1 March 2, 2000 03:57

All times are GMT -4. The time now is 02:33.