In fluid dynamics, a vortex is a region in a fluid in which the flow revolves around an axis line, which may be straight or curved. Vortices form in stirred fluids, and may be observed in smoke rings, whirlpools in the wake of a boat, and the winds surrounding a tropical cyclone, tornado or dust devil.
Vortex created by the passage of an aircraft wing, revealed by colored smoke
Vortices formed by milk when poured into a cup of coffee
A Kármán vortex street is demonstrated in this photo, as winds from the west blow onto clouds that have formed over the mountains in the desert. This phenomenon observed from ground level is extremely rare, as most cloud-related Kármán vortex street activity is viewed from space
The Crow instability of a jet aeroplane's contrail visually demonstrates the vortex created in the atmosphere (gas fluid medium) by the passage of the aircraft.
In physics, physical chemistry and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids—liquids and gases. It has several subdisciplines, including aerodynamics and hydrodynamics. Fluid dynamics has a wide range of applications, including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting weather patterns, understanding nebulae in interstellar space and modelling fission weapon detonation.
The transition from laminar to turbulent flow
