1-Wet foams, are dispersions of gases in a liquid with a high-volume fraction of liquid ranging from 5 to 20-30%. The gas bubbles form perfect spheres. 2-Dry foams are characterized by a liquid volume fraction that is below 5%. In these foams, the bubbles undergo deformation, taking on polyhedral shapes, and they are separated by thin films. Foam quality (Γ) is the volumetric ratio of gas-phase (VG) to gas/liquid-phase (VL) i.e. Gravitational drainage of foam is the phenomenon wherein a liquid drains out of a foam structure due to the influence of gravity. This process involves the dynamic interplay of gravity, surface tension, and viscous forces, leading to the depletion of liquid within the foam. As a result, the upper part of the foam tends to dry out. The concavity of the surface, particularly at the edges of the tray.