Airplane Pilot's As Physicists
Uncle Al wrote:
2) Bernoulli's law is strictly a 2-D analysis.
Are you sure? I ask because I know the application of Bernoulli's theorem
to airfoils is typically restricted to 2-D and wondering if that is what
you meant. Otherwise there doesn't appear to be any dimensional assumption
in the theory itself or its derivation. Here's one typical presentation of
Bernoulli's theorem:
"In the steady motion of an inviscid fluid the quantity
p/rho + K
is constant along a streamline, where p is the pressure, rho is the density
and K is the energy per unit mass of fluid."
And the definition of streamline also appears void of dimensional
restriction:
"A line drawn in the fluid so that its tangent at each point is in the
direction of the fluid velocity at that point is called a streamline."
Both quotes from "Theoretical Aerodynamics" by L. M. Milne-Thomson.
So unless I'm mistaken (and I could be) it appears that Bernoulli's
theorem:
1) Applies to compressible or incompressible fluids.
2) Does not necessarily apply to viscous fluid flows.
3) Does not necessarily apply to turbulent flow (it's not "steady motion".)
4) Does not itself define the flow streamlines.
5) Is not restricted to 1 or 2 dimensional analysis.
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