Lagrange stream function

Lagrange stream function

[lə′gränj ′strēm ‚fəŋk·shən]
(fluid mechanics)
A scalar function of position used to describe steady, incompressible two-dimensional flow; constant values of this function give the streamlines, and the rate of flow between a pair of streamlines is equal to the difference between the values of this function on the streamlines. Also known as current function; stream function.