"When skin effect is present, the current is always redistributed over the
conductor cross section in such a way as to make most of the current flow where
it is encircled by the smallest number of flux lines. This general principle
controls the distribution of current irrespective of the shape of the conductor
involved. Thus, with a flat strip conductor (figure reference not shown) the
current flows primarily along the edges, where it is surrounded by the smallest
amount of flux, and the true or effective resistance will be high because most
of the strip carries very little current. (A reference to the missing figure)
makes clear that it is not the amount of conductor surface that determines the
resistance to alternating current but rather the way in which the conductor
material is arranged."
On 4/26/2018 6:35 PM, Dauer, Edward wrote:
Since I don't know what precedes the word "thus" in the quotation below I
would ask if someone could explain this phenomenon for me.
I am trying to visualize this with a thought experiment. In an earlier post
someone (Skip?) mentioned that early transmission lines were sometimes hollow
copper tubes, to respect the fact that AC flows only on the outside of a
conductor. So, imagine a hollow tube carrying RF (which may approximate the
fast rise and fall times of a high voltage strike). Current is flowing all
over the surface, I gather. Now squeeze the tube along its length so that a
cross section becomes an ever flatter ellipse. At the last instant squeeze it
so that the sides are in contact with each other. What happens to the current
flow as that squeezing occurs? Is it still all around the squished tube until
the instant the two sides join? And then it all flows primarily along the
edges of the now flat conductor? Howcome?
Tnx,
Ted, KN1CBR
------------------------------
Message: 3
Date: Wed, 25 Apr 2018 18:45:39 -0700
From: Wes Stewart <[email protected]>
To: [email protected]
Subject: Re: [Elecraft] OT: Grounding Question
Message-ID: <[email protected]>
Content-Type: text/plain; charset=utf-8; format=flowed
Radio Engineering and Radio Engineer's Handbook are two different critters.? My
copy of Radio Engineering is the third edition and the pertinent
information is
on p.20.
To partially quote: "Thus, with a flat-strip conductor, the current flows
primarily along the edges."
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