Any one know, how to simulate falling droplet on a vertical wall (boundary layer study + heat and mass transfer study) IN CFX 10

Regards

Just getting the cold flow model right would require carefull validation against experimental data. Surface tension effects on real surfaces are notoriously finicky e.g. composition, contamination, roughness, ...

If you dont have good experimental data to validate against, you are going to have to do that first anyway, which may make using CFD redundant.