Boundary Layer Physics

Boundary layer physics describes the thin region of fluid (like air or water) that directly interacts with a solid surface, such as an airplane wing or car body. In this zone, the fluid's speed transitions from zero at the surface (due to friction) to its free-stream velocity farther away. Understanding this layer is crucial because it influences drag, heat transfer, and how fluids flow around objects. The behavior within the boundary layer—whether smooth or turbulent—affects the efficiency, performance, and safety of many engineering systems.