Ideal liquid
In physics , hydrostatics and hydrodynamics, an ideal fluid is the idealized model representation of a fluid . Although this model represents a great simplification, many physical processes can already be understood and described mathematically with it.
The most important property of an ideal liquid is that it is not viscous , i. H. no internal friction or has:
Because of this frictionlessness, no energy is lost mechanically in the ideal liquid ; on the other hand, in real liquids, energy is converted into heat by frictional forces .
In addition, an ideal liquid does not exert any resistance to changes in shape and can therefore be regarded as ideally liquid in contrast to the rigid body , which resists any change in shape.
Other properties
Except for the internal frictionlessness of the liquid molecules , the properties of ideal liquids are not uniformly defined. The following defining properties can also apply to ideal liquids:
- Incompressibility
- no thermal conductivity
- no surface tension
- Heavy unemployment.
Regularities
In resting ideal liquids is everywhere the same volume with negligible force (eg. As gravity) hydrostatic pressure . If a force exerts a piston pressure on an ideal liquid (in a container closed all around) via a movable piston with the surface , this pressure spreads inside and to all sides simultaneously and evenly. It applies
Because the liquid is at rest, the pressure exerts an orthogonal force on each interface that is proportional to the area.
Individual evidence
- ^ Karl Wieghardt: Theoretical Fluid Mechanics . Universitätsverlag Göttingen, 2006, ISBN 978-3-938616-33-8 (accessed December 14, 2011). P. 12
- ↑ Tsutomu Kambe: Elementary fluid mechanics . World Scientific, 2007, ISBN 978-981-256-416-0 (Accessed December 14, 2011). P. 26