Deformation is the rate of change of shape of fluid bodies. Meteorologically, this quantity is very important in the formation of atmospheric fronts, in the explanation of
cloudA cloud is a visible mass of liquid droplets or frozen crystals made of water and/or various chemicals suspended in the atmosphere above the surface of a planetary body. They are also known as aerosols. Clouds in Earth's atmosphere are studied in the cloud physics branch of meteorology...
shapes, and in the diffusion of materials and properties.
Equations
The deformation of horizontal wind is defined as
, where
and
, representing the derivatives of wind component. Because these derivatives vary greatly with the rotation of the coordinate system, so do
and
.
Stretching direction
The deformation elements
and
(above) can be used to find the
direction of the dilatation axis, the line along which the material elements stretch (also known as the
stretching direction). Several flow patterns are characteristic of large deformation: confluence, diffluence, and shear flow.
, also known as
stretching, is the elongating of a fluid body along the flow (streamline convergence).
, also known as
shearing, is the elongating of a fluid body normal to the flow (streamline divergence).
The source of this article is
wikipedia, the free encyclopedia. The text of this article is licensed under the
GFDL.