[Moreza7]

Hello,

I use ANSYS Fluent to simulate a heat pipe using VOF multiphase model.

I used mass transfer condition from water(liquid) to the water vapor (evaporation), but as you know, after the fluid evaporates in a heat pipe, it will condense in the condensation zone.

Should I also add the mass transfer condition from water vapor to water(liquid) (for condensation) to the mass transfer conditions?

Regards.

[vinerm]

If you are using inbuilt Evaporation-Condensation model, i.e., either Lee or Thermal Phase Change model, then you do not need to enable two mass transfer mechanisms since these models take care of both, evaporation and condensation. If you are using one of your own model via UDF or some other mechanism, then you might need to enable two mechanisms, depending upon the model you are using.