i want to simulate the process of liquid water transforming into vaporate water flowing in a hot duct. But i don't know which model i should used. Because all the multiphase models don't considerate the evaporation progress. what should i do?

Any help will be appreciated! Thank you!

Hi!

I think the best possibility is VoF multiphase model with UDF for mass transfer (you have an example for UDF defining mass transfer due to incerased temperature).

regards

MATEUS

Thank you for your help. But the vof multiphase model just model the two phases which don't penetrate into eath other. The most difficult thing i face is how to considerate the heat transfer between the two phases and the transforming of liquid into gas. i appreciate any help. Thanks again!

Hi!

If the two phases do not penetrate each other means that there is a defined boundary between them (in your case boiling - liquid and wapour). The case where they are penetrating each other is for example mixture of water and alcohol (no boundary between liquids can be defined).

As I told you you can find an example of heat transfer and mass transfer in fluent UDF documentaion. Hm. I forgot to ask you - which fluent wersion are you using - with fluent 6.1 it's possible to do this, but I'm not shure for previous versions.

Anyway - check UDF documentation (FLUENT 6.1 - chapter - 4.4.2).

REGARDS, AND GOOD LUCK

MATEUS

Hi!

I have sent you the documentation - i hope the adress was correct - I've had some problems with it...

have fun

MATEUS

It's a great help! Thank you very much.