bongodriver |
09-06-2011 10:56 PM |
Quote:
Originally Posted by whoarmongar
(Post 332128)
Viscosity only applies to liquids.
As this is a flight sim, not a sub sim viscosity does not apply at any altitude.
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Gases
Viscosity in gases arises principally from the molecular diffusion that transports momentum between layers of flow. The kinetic theory of gases allows accurate prediction of the behavior of gaseous viscosity.
Within the regime where the theory is applicable:
Viscosity is independent of pressure and
Viscosity increases as temperature increases.[12]
James Clerk Maxwell published a famous paper in 1866 using the kinetic theory of gases to study gaseous viscosity.[13] To understand why the viscosity is independent of pressure, consider two adjacent boundary layers (A and B) moving with respect to each other. The internal friction (the viscosity) of the gas is determined by the probability a particle of layer A enters layer B with a corresponding transfer of momentum. Maxwell's calculations showed him that the viscosity coefficient is proportional to both the density, the mean free path and the mean velocity of the atoms. On the other hand, the mean free path is inversely proportional to the density. So an increase of pressure doesn't result in any change of the viscosity.
Of course this contradicts my explanation but it does prove that gas has viscosity, as far as saying air is less hazy at altitude....thats just fact and I am speaking from 2800 hours of flying experience, the only time I have seen haze at altitude is when passing through a temparature inversion.
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