Reynolds averaging
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| - | Where <math>T</math> is a long enough time to average out the | + | Where <math>T</math> is a long enough time to average out the fluctuations in <math>\Phi</math>. |
| - | Reynolds averaging is often used in fluid dynamics to separate turbulent fluctuations from the mean-flow. The term | + | Reynolds averaging is often used in fluid dynamics to separate turbulent fluctuations from the mean-flow. The term Reynolds averaging originates from [[Osborne Reynolds]], who was the first to use this type of averaging in fluid dynamics. |
Latest revision as of 09:59, 7 September 2005
Reynolds averaging refers to the process of averaging a variable or an equation in time. Let 
be any dependent variable that varies in time. This variable can be decomposed into a fluctuating part, 
and an average part 
in the following way:
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|
(1) |
|
|
Where 
is a long enough time to average out the fluctuations in .
Reynolds averaging is often used in fluid dynamics to separate turbulent fluctuations from the mean-flow. The term Reynolds averaging originates from Osborne Reynolds, who was the first to use this type of averaging in fluid dynamics.
