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Viscous work term query

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Old   December 6, 2010, 03:34
Default Viscous work term query
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siw
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Hi,

For the total energy equation there's a check box to include the work due to viscous stresses term in the energy equation.

Why is it that by default this term is omitted from the energy equation and requires being separately activated? What sort of simulations require the total energy equation but not the viscous work term (it's not a Euler situation)? Would it not be better to solve the whole equation by default?

My simulation (Mach no. 0.85, Re no. 5x10^6) shows a 20 deg C higher surface temperature (on average) with the viscous work term included (see image).

Thanks
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Last edited by siw; December 6, 2010 at 06:14. Reason: Added image
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Old   December 6, 2010, 06:41
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Glenn Horrocks
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Viscous work is insignificant for most compressible flow models. Looks like you have found one where it is not. There is no point adding extra terms in the equation when they do not do anything for most models.
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