TITLE: Change in Surface Tension of Inviscid Flow
QUESTION [0 upvotes]: If we have a stationary fluid assumed inviscid (and hence zero viscosity), it's well known that since there are no nonzero net resultant intermolecular forces on the fluids molecules, it possess' no surface tension (zero surface tension).
Now suppose we have inviscid flow (I.e. the velocity of the fluid is not necessarily zero, but not viscous), then is it possible for the fluid to possess a change in surface tension? I.e. a surface tension gradient along its flow?
Thanks!

REPLY [1 votes]: Surface tensions arise in liquids due to intermolecular/interactomic forces. They are secondary bonding forces. Liquid surfaces are self-renewing. They cannot be treated as a static elastic medium in the same way that solids or solid surfaces would be treated. As a liquid surface is stretched to increase its area, molecules from the bulk liquid move into the surface more easily than stretching the collections of intermolecular/interatomic bonds further in their potential well. The surface tension of a liquid is therefore independent of the magnitude of any externally applied force that pulls along the plane to the surface.
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