Controlling heat transfer in VOF model
 

Hi,
my model is a stationary tank of water and atmospheric air above it. temperature of water is 30C and air is 25. So there is difference in temperature in free surface. because of that vof starts to transfer heat between phases which is not happening in real (at least by the rate that vof guess! the rate is small when the air is stationary).
my question is how is it possible to control the rate of heat transfer or somehow to prevent heat transfer between phases? of course it is not possible by GUI or maybe TUI. is there a UDF or a macro that can solve my problem?
every help will be appreciated.