Consider the motion where the liquid is coming from an infinite
distance between two parallel walls at a distance xx´ (fig. 4), and
issues in a jet between two edges A and A´; the wall xA being bent at
a corner B, with the external angle [beta] = ½[pi]/n.
The theory of conformal representation shows that the motion is given
by
_ _
| [root](b - a´·u - a) + [root](b - a·u - a´) |^1/n
[zeta] = | ------------------------------------------- | , u = ae^(-[pi]w/m); (5)
|_ [root](a - a´·u - b) _|
where u = a, a´ at the edge A, A¹; u = b at a corner B; u = 0 across
xx´ where [phi] = [oo]; and u = [oo], [phi] = [oo] across the end JJ´
of the jet, bounded by the curved lines APJ, A´P´J´, over which the
skin velocity is Q. The stream lines xBAJ, xA´J´ are given by [psi] =
0, m; so that if c denotes the ultimate breadth JJ´ of the jet, where
the velocity may be supposed uniform and equal to the skin velocity Q,
m = Qc, c = m/Q.
If there are more B corners than one, either on xA or x´A´, the
expression for [zeta] is the product of corresponding factors, such as
in (5).
Restricting the attention to a single corner B,
/ Q \^n [root](b - a´·u - a) + [root](b - a·u - a´)
[zeta]^n = ( --- ) (cos n[theta] + i sin n[theta] = -------------------------------------------, (6)
\ q / [root](a - a´.u - b)
/ Q \^n / Q \^n
ch n[omega] = ch log( --- ) cos n[theta] + i sh log ( --- ) sin n[theta]
\ q / \ q /
/b - a´ /u - a´
= ½([zeta]^n + [zeta]^(-n)) = / ------ / ------ (7)
\/ a - a´ \/ u - b´
/ Q \ / Q \^n
sh n[Omega] = sh log ( --- ) cos n[theta] + i ch log ( --- ) sin n[theta]
\ q / \ q /
/b - a´ /u - a´
= ½([zeta]^n - [zeta]^(-n)) = / ------ / ------ (8)
\/ a - a´ \/ u - b´
[oo] > a > b > 0 > a´ > -[oo] (9)
and then
d[Omega] 1 [root](b - a´·b - a´) dw m
-------- = - -- ---------------------------, -- = - ------ (10)
du 2n (u - b)[root](a - a·u - a´) du [pi]u´
the formulas by which the conformal representation is obtained.
For the [Omega] polygon has a right angle at u = a, a´, and a zero
angle at u = b, where [theta] changes from 0 to ½[pi]/n and [Omega]
increases by ½i[pi]/n; so that
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Elsewhere in the archive
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account