Ergodicity: Difference between revisions

From Glossary of Meteorology
imported>Perlwikibot
(Created page with " {{TermHeader}} {{TermSearch}} <div class="termentry"> <div class="term"> == ergodicity == </div> <div class="definition"><div class="short_definition">(<br/>''Also cal...")
 
imported>Perlwikibot
No edit summary
 
Line 9: Line 9:
   </div>
   </div>


<div class="definition"><div class="short_definition">(<br/>''Also called'' statistical stationarity.) For [[turbulent flow]], the property of having the spatial,  temporal and [[ensemble averages]] all converge to the same mean.</div><br/> <div class="paragraph">This can only be true if the flow is stationary and homogenous. As a consequence, the [[autocorrelation]]  of an [[ergodic]] flow [[variable]] is zero as either the averaging length, time, or number  of realizations goes to infinity. <br/>''See'' [[ensemble average]].</div><br/> </div><div class="reference">Hinze, J. O. 1975. Turbulence. 2d ed., McGraw&ndash;Hill, . p. 5. </div><br/>  
<div class="definition"><div class="short_definition">(''Also called'' statistical stationarity.) For [[turbulent flow]], the property of having the spatial,  temporal and [[ensemble averages]] all converge to the same mean.</div><br/> <div class="paragraph">This can only be true if the flow is stationary and homogenous. As a consequence, the [[autocorrelation]]  of an [[ergodic]] flow [[variable]] is zero as either the averaging length, time, or number  of realizations goes to infinity. <br/>''See'' [[ensemble average]].</div><br/> </div><div class="reference">Hinze, J. O. 1975. Turbulence. 2d ed., McGraw&ndash;Hill, . p. 5. </div><br/>  
</div>
</div>



Latest revision as of 15:11, 20 February 2012



ergodicity

(Also called statistical stationarity.) For turbulent flow, the property of having the spatial, temporal and ensemble averages all converge to the same mean.

This can only be true if the flow is stationary and homogenous. As a consequence, the autocorrelation of an ergodic flow variable is zero as either the averaging length, time, or number of realizations goes to infinity.
See ensemble average.

Hinze, J. O. 1975. Turbulence. 2d ed., McGraw–Hill, . p. 5.


Copyright 2024 American Meteorological Society (AMS). For permission to reuse any portion of this work, please contact permissions@ametsoc.org. Any use of material in this work that is determined to be “fair use” under Section 107 of the U.S. Copyright Act (17 U.S. Code § 107) or that satisfies the conditions specified in Section 108 of the U.S.Copyright Act (17 USC § 108) does not require AMS’s permission. Republication, systematic reproduction, posting in electronic form, such as on a website or in a searchable database, or other uses of this material, except as exempted by the above statement, require written permission or a license from AMS. Additional details are provided in the AMS Copyright Policy statement.