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It seems to me the description given by Cliff Parker's student has some----------
merit.
In the book "Vacuum Technology" by Andrew Guthrie,
he says "ejector pumps... depend for their pumping action on entrainment
of gas by viscous drag and by diffusion of gas into the vapor at the
boundary of a dense vapor stream."
-----------
When Clifford Parker described his student's response as "The air stream
is blowing the air particles from around the top of the ball away..."
this sounded to me like a description of the ejector process.
----------
I think Bernoulli is fine for describing incompressible fluids flowing
in pipes. Textbooks warn that Bernoulli's equation is useful for
qualitative descriptions, but Bernoulli can be grossly inaccurate
compared to actual experiments. I think this is because we extend
Bernoulli way past the boundaries for which it is valid. To be valid we
need incompressible fluid, we need zero viscosity, and we need
steady-state streamlined flow.