A “point source” specifically represents a location in the flow field where fluid is injected or removed at a constant rate from a single point. A point source can be visualized as an imaginary or real location where fluid is introduced into the flow or extracted from it uniformly in all directions.
- ϕ is the potential function at a distance r from the point source.
- λ is the strength of the point source (also known as the source/sink strength).