👉 Crossflow is a concept in fluid dynamics that describes the movement of fluids or gases between two surfaces. It involves the transfer of energy and momentum from one medium to another, typically through a small opening (such as a pipe or a channel). Crossflows can occur at different scales, such as at the surface of Earth's oceans or within the walls of buildings, and are often used in various engineering applications, including water treatment systems, gas pipelines, and hydraulic systems.