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| {{about|extensional viscosity||Rheology}}
| | The writer is called Wilber Pegues. Invoicing is my occupation. Mississippi is where his home is. It's not a common thing but what I like performing is to climb but I don't have the time recently.<br><br>Here is my homepage ... [http://bigpolis.com/blogs/post/6503 free psychic reading] |
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| '''Extensional viscosity ''' (also known as '''elongational viscosity''') is a [[viscosity]] coefficient when applied [[Stress (physics)|stress]] is [[extensional stress]].<ref>Barnes, H.A. "A handbook of elementary rheology", Institute of non-Newtonian Fluid Mechanics, 2000</ref>
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| :This parameter is often used for characterizing polymer solutions.
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| ''Extensional viscosity'' can be measured using rheometers that apply ''extensional stress''. [[Acoustic rheometer]] is one example of such devices. | |
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| :<math>\eta_e = \frac{\sigma_n}{\dot{\varepsilon}}\,\!</math>
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| where
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| :<math>\eta_e\,\!</math> is the '''extensional viscosity''' or '''elongational viscosity'''
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| :<math>\sigma_n\,\!</math> is the '''normal stress''': <math>\sigma_n = \frac{F}{A}\,\!</math> | |
| :<math>\dot{\varepsilon}\,\!</math> is the '''rate of strain''': <math>\dot{\varepsilon} = \frac{1}{L}\frac{dL}{dt}\,\!</math>
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| For a [[Newtonian Fluid]], the elongational viscosity is three times the shear viscosity which can be derived using the [[continuity equation]] for incompressible fluids.
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| :<math>\eta_e = 3\eta\,\!</math>
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| ==References==
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| {{reflist}}
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| ==See also==
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| *[[Rheology]]
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| *[[Viscosity]]
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| *[[Trouton's ratio]]
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| {{DEFAULTSORT:Extensional Viscosity}}
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| [[Category:Fluid dynamics]]
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| [[Category:Viscosity]]
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| {{fluiddynamics-stub}}
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Latest revision as of 16:56, 6 January 2015
The writer is called Wilber Pegues. Invoicing is my occupation. Mississippi is where his home is. It's not a common thing but what I like performing is to climb but I don't have the time recently.
Here is my homepage ... free psychic reading