Reynolds decomposition
In fluid dynamics and turbulence, Reynolds decomposition is a mathematical
technique to separate the average and fluctuating parts of a quantity.
For example, for a quantity <math>u<math> the decomposition woud be:
- <math>
u = \overline{u} + u'<math> where <math>\overline{u}<math> denotes the time average of <math>u\,<math> (often called the steady component), and <math>u'\,<math> the fluctuating part (or perturbations). The perturbations are defined such that their time average equals zero.
This allows us to simplify the Navier-Stokes equations by substituting in the sum of the steady component and perturbations to the velocity profile and taking the mean value. The resulting equation contains a nonlinear term which gives rise to turbulence.
See also
Categories: Fluid dynamics | Stub