Hi Keith, thank you for your interesting post.
...
> But I don't think you'll find any "gurus" here.
I don't know, maybe there are some:) Someone might even like to name a
colleague whom they have found to be especially helpful, enlightening &
inspiring?
Regarding your following question, I don't know for sure, but I will tell
you what I think. (I do also have an interest in physics, but I am not a
physicist:) )...
...
> If you look at:
>
[quoted text clipped - 5 lines]
> dissimilar conductive material and subjected to a temperature gradient
> across its length (figure d is most instructive).
Yes, I observe that in this illustration, the enclosed dissimilar material
is in a "single slab" that spans the temperature difference region. I
believe the "single slab" point is the critical one - I will explain below.
> This phenomenon is utilised in the field of non-destructive materials
> testing to identify the presence of inclusions or impurities in metals
> by detecting the influence of the thermoelectrically generated
> electromagnetic field outside the surface of the material using very
> accurate sensors.
I believe in this case that the metal is an alloy, and as such would still
act as a "slab" of homogeneous material with a particular Seebeck
coefficient. I believe that the level of impurity would affect the Seebeck
coefficient, and this can be measured. I don't know for sure - I am guessing
that his is how it's done? If you have a web link, I would be interested to
have a look.
> An important aspect of this phenomenon is that it appears to be
> reversible - i.e. an externally applied electromagnetic field of the
> appropriate characteristics would have the effect of inducing the eddy
> current and corresponding temperature gradient in the dissimilar
> materials.
Yes, in thinking about what the Seebeck and Peltier effects are doing, it is
helpful to consider both the "voltage generation" and the reverse case of
"temperature difference generation".
> If you now look at:
>
[quoted text clipped - 7 lines]
> thermoelectric and/or electromagnetic properties of a typical dental
> amalgam?
I believe it won't work because even though the dissimilar metals are
enclosed, they are not in a single slab - they are in "micro slabs" or
particles. The eddy currents around each "micro slab" would cancel with
adjacent ones (sum to zero), not enabling an eddy current loop to form, and
hence no generated magetic field.
...I could be wrong but on my first pass it seems like this could be the
case. I'm not sure without thinking about it more deeply.
Tony Burch