Sessile Drop Method
Definition - What does Sessile Drop Method mean?
The Sessile drop method is performed with an optical tensiometer to determine the contact angle of a liquid on a surface. It is the standard arrangement for optical measurement of contact angle. A liquid sample is placed on a surface using a syringe. The inter-molecular forces of cohesion and adhesion determine the contact angle created.
When the contact angle is less, the adhesive forces are stronger and the liquid molecules interact more with the solid molecules than the liquid ones. When the contact angle is large, the cohesive forces are stronger and the liquid molecules interact more among themselves than with the solid molecules.
Trenchlesspedia explains Sessile Drop Method
Force is exerted due to the contact between liquid and solid interface which may be either of repulsion or attraction depending on the surface tension of the liquid and surface energy of the surface. The results will include contact angle and the capability of the surface to wet. High contact angle indicates a surface with low wettability, and low contact angle indicates a surface with high wettability.
Pipes that do not have the appropriate contact angle with the liquid they carry can be rehabilitated using trenchless methods such as cured-in-place pipe (CIPP), sliplining and pipe bursting.