# Speed field

A **speed field** is a physical field that assigns a speed to every location in space . Since velocities are represented using vectors , the velocity field is a vector field , i. H. each point of the space must have both a velocity amount be as well assigned to one direction.

Velocity fields describe velocities in space without considering the physical causes ( forces ) of the movements ( kinematics ). They therefore have the character of a mathematical aid and can be calculated from potentials or forces. In many cases the speed of a body depends only on its position and not on time; H. the velocity field is stationary and a description of the system is therefore relatively easy.

Velocity fields play a major role as flow fields in fluid dynamics . For example, water flowing through a pipe can be described with the help of a velocity field. The use of these fields has also become indispensable in other cases: e.g. B. the Navier-Stokes equation has a term that is directly related to the velocity field of the medium . A decisive advantage of the velocity fields in fluid dynamics is that they can be measured experimentally .

## literature

- Hartmann Römer , Michael Forger: Elementary field theory: electrodynamics, hydrodynamics, special relativity theory . VCH, Weinheim 1993, ISBN 3-527-29065-6 .
- Adolf J. Schwab:
*Conceptual world of field theory*. Springer Verlag, ISBN 3-540-42018-5