The presentation will report the 3D volume fraction of liquid refrigerant R1336mzz(Z) as it falls from a small orifice and interacts with heated horizontal tubes, capturing the dynamic transition of the liquid film. Initially, the refrigerant undergoes free-fall before striking the upper tube, forming a stationary film at the stagnation point. Gravity then drives the film downward, spreading it axially and circumferentially, with thinning indicated by a color shift from red to light green. Dry-out appears in regions with insufficient flow, while droplet impacts generate surface waves. Heat transfer is absent in certain areas due to dry-out from high heat flux. Two mechanisms contribute to dry-out: film detachment when critical heat flux is exceeded, and film breakup into rivulets when the ...