On Mar 25, 10:28*am, Cecil Moore wrote:
Keith Dysart wrote:
Cecil Moore wrote:
Point is, energy can be stored and released at a
later time. You earlier said that reactances do not
store energy for release at a later time yet that
is exactly what reactances do.

Yes indeed. And what I have said, is that when this is
happening it is always possible to identify the element
which is storing the energy and provide the function
that describes the energy flow in and out of the
element. It is this identification and function that
I keep asking for to back up the handwaving claim that
you have been making.

Good grief, Keith, do you not know how to track the
energy flow into and out of a reactance during an RF
cycle? Isn't that covered in EE201, "Alternating
Current Circuits", by Kerchner and Corcoran, 3rd
edition (c)1951? Quoting page 19:

"The implication is that the inductive element
receives energy from the source during one-quarter
of a cycle of the applied voltage and returns exactly
the same amount of energy to the driving source during
the next one-quarter of a cycle."

The equations are provided if you really need them.
Hint: A shorted 1/8WL stub is inductive.

Instead of writing two lines identifying the element
and providing the function describing its energy flow,
you write 14 lines tell me I should do it.

But my explanations do not require this element to
store and return the "interference energy".

You should consider that perhaps your inability to
identify the element and its energy function really
calls into question your concept of "interference
energy" being stored and returned later.

Bzzt. Power is the rate of change of energy.

Sorry, you are wrong about that.
*From the IEEE Dictionary: "power - the rate of
generating, transferring, or using energy".

Power is a rate, not a rate of change. The
energy flow can be constant, i.e. rate of change
equal zero.

When energy is transferred, the quantity is decreasing
in the supplier and increasing in the receiver. From
the supplier's perspective, this is a negative flow and
from the receiver's perspective, a positive flow.

In calculus terms, energy flow is the derivative of the
quantity of energy, i.e. the rate of change of the
amount of energy. The slope of the curve recording the
amount of energy can be negative, even though the amount
of energy is always positive.

Please re-read all the equations with "(t)". There
is no "cos(theta)" factor when "(t)" is present.

I assume that exponential (phasor) notation for the
instantaneous values of the interfering voltages could
be used in which case there would indeed be a cos(theta)
present.

No. "cos(theta)" only appears in the equations describing
the average, and not in those equations that describe the
actual function of time.

[snip]
Read it as Pr.correction(t) to emphasize that it is not
average power of which I am writing. Then it is not
interference.

That statement makes it obvious that you don't understand
interference. When instantaneous values are being used,
if [V1(t)^2 + V2(t)^2] NOT= [V1(t) + V2(t)]^2, then
interference is present. Did you miss Physics 201?

I suppose, if you want to rename superposition as interference.
But none of my basic circuit theory books use the word
interference when discussing superposition.

Because the powers imputed to the
constituent voltages of superposition do not represent
actual energy flows.

That statement is a violation of the wave reflection
model. Do you really believe that when you look
yourself in the mirror that those reflections are
devoid of energy? If so, please feel free to prove
your assertion.

If the powers imputed to the constituent voltages of
superposition did represent actual energy flows, then
you would be able to simply add them to get the total
flow, since energy can not be created or destroyed.

The fact that a correction needs to be applied when
adding them is proof that they can not be actual energy
flows.

But you know that, and that is why you have to search
for where this correction, that which you call the
"interference energy", goes. Because only if you can
account for it, can you claim that it is an actual
energy flow, which is needed to make you explanations
agree with conservation of energy. But in this example
you can not account for this "interference energy".
You have not identified the element that stores it nor
being able to obtain a function which describes the flow
into that element. You should take this as a reason to
call into question the whole idea that this "interference
energy" is an actual energy flow.

But you have to be cautious that you are applying
conservation to powers that represent actual energy
flows.

Reflected waves contain energy whether from your mirror
or from a mismatched load at the end of a transmission
line. You are arguing that the wave reflection model
is wrong. Please prove it.

If *your* "wave reflection model" includes the idea that
Pref always represents an actual energy flow, then *your*
"wave reflection model" is wrong.

Or perhaps, these powers of which you speak do not
represent actual energy flows and therefore your
requirement that they need accounting is incorrect
and all of your attempts to explain them, unnecessary.

Yes, perhaps the wave reflection model is wrong but
that makes your argument not with me, but with Ramo,
Whinnery, Johnson, Chipman, Slater, Hecht, and Walter
Maxwell. Good luck on winning that one.

I am not convinced. It is clear that *your* "wave reflection
model" is wrong, but I have not seen these other authors
invest any effort in trying to explain where the reflected
power goes. Perhaps they realized it was a meaningless
question and their "wave reflection models" do not require
that the Pref represent an actual energy flow.

The difficulty of accounting for these powers is entirely
consistent with them not representing the actual flow
of energy.

No, it is perfectly consistent with a large degree
of ignorance which few people desire to alleviate.

Ignoring the role of interference and lumping all the
energy components into a mashed potato salad is one
method of sweeping everything under the rug so you
can ignore the problem instead of solving it.

I am still waiting for the simple answer as to which
element stores and returns this "interference energy" and
the function that describes the flow into this element.

Or possibly, the premise that these powers represent
actual energy flows is flawed.

Feel free to prove the wave reflection model wrong.

That your "wave reflection model" is inconsistent with
conservation of energy (until you identify the storage
element and its energy transfer function) should be proof
enough.

This turns out, however, just to be an ideosyncracy of the math,
much like the way Pf-Pr is the actual energy flow in the transmission
line because of the way that Vf and Vr are derived from Vactual

Feel free to prove the math wrong.

The math is correct. It is the interpretation that is in error.

Pf-Pr is always equal to Pnet simply because of the way that Vfor
and Vref are computed. Even though Pf-Pr adds to the actual measured
energy flow, it does not mean that Pf and Pr are actual energy flows.
They MUST add simply becase of the way they are computed.

The same is true for some of the "proofs" in your other papers. The
successful equalities are simply a consequence of the way the numbers
being added are computed. A successful equality does not necessarily
prove an interpretation.

It would be good, if just for a day, you let go of the
idea that Preflected represents an actual energy flow.

I will do that the day that you prove those reflections
from your mirror, that allow you to see yourself each
morning, contain zero energy.

This is indeed the root of the problem. You need to let go
of the mirror just long enough to get over the hump. As it
stands, whenever you approach the hump, you think about the
mirror and refuse to see what might be on the other side of
the hump. That is why I suggest letting go of the mirror
just for a short while. Explore to see if there exists a
completely self consistent set of explanations on the other
side of the hump. You will find it to be so. But this can
only happen if you let go of the mirror long enough to get
over the hump.

If it doesn't work out, you can always pick up the mirror
again. There is nothing to lose by temporarily doing some
exploration without the mirror.

[snip]

...Keith