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Old   January 28, 2011, 05:44
Default treating unresolved scale
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Hello, every one.
I have a question with filtering in LES.

Let original flow u and filtered flow <u>.
Then unresolved scale become u'=u-<u>

If I filter the unresolved scale, i.e., <u'>,
I want to know whether this value will be 0 or not?

Thank you for reading!
YE.
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Old   February 14, 2011, 14:34
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The answer is "no", unless you use a projective filter. Try by yourself in MATLAB with a simple 1D function (sum of sines) and different filters. The spectral cut off is the only filter which gives exactly 0.
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Old   February 14, 2011, 21:51
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Quote:
Originally Posted by sbaffini View Post
The answer is "no", unless you use a projective filter. Try by yourself in MATLAB with a simple 1D function (sum of sines) and different filters. The spectral cut off is the only filter which gives exactly 0.

Thank you for your help!
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