Learn about the proof of Lamb-Chaplygin dipole

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The discussion focuses on understanding the proof of the Lamb-Chaplygin dipole, with participants seeking clarification on specific aspects of the proof. Two links are provided for reference, with the first link potentially containing the proof on pages 166-174. The proof involves using a stream function to derive a single equation in terms of ψ, leading to a transformed equation in polar coordinates. Participants are encouraged to explain the steps and concepts, particularly the significance of the green lines in the context of the proof. Overall, the conversation aims to deepen understanding of the Lamb-Chaplygin dipole solution and its mathematical framework.
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I learn about Lamb-Chaplygin dipole and try to find the proof of this topic.
so I found the next link (is named: link1): https://docs.google.com/file/d/0B3-t1lLIJWOLc2NmT1RIWV9HOWs/edit?usp=sharing&pli=1

In addition, I found another link (is named: link2): http://ics.org.ru/doc?pdf=875&dir=e

can anyone tell me please on which pages (and of which link) the proof is found?
I think the proof is found only at link1: 166-174 but I'm not sure.

any help appreciated!
 
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explanation the next steps in other words (dipole)

I am trying to understand the lamb-chaplygin dipole solution.
can someone explain me the green lines in other words please?

this is the proof:

When introducing the stream function, the steps that you usually take are as follows:
1) replace u and v by the stream function.
2) Derive the horizontal momentum equation (for u) with respect to y and the other with respect to x.
3) Eliminate the pressure term, to end up with a single equation in ψ.

so:

v = -∂ψ/∂x, u = ∂ψ/∂y

(∂^2)ψ/∂x^2 + (∂^2)ψ/∂y^2 = f(ψ)

if we put f(ψ) = -(k^2)*ψ. where k is a constant, and transform to polar coordinates r, θ, we get:

(d^2)ψ/ dr^2 + (1/r) * (dψ/dr) + (1/r^2) * (d^2)ψ/ dθ^2 + (k^2)*ψ = 0

which is satisfied by:
29y8fo.jpg


where Js is a bassel's function.


any help appreciated! thanks!
 
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