Dave-
The parameter that controls the LENR should extend throughout the reacting
material and affect the reaction in a similar manner to be effective. My guess
is that it is temperature that changes the reaction rate as the temperatures
rises and, then, reduces the rate, if the temperature gets to high by allowing
the configuration of the active nano structure to change.
There may be a magnetic field that aligns active nano particles or atoms to
promote the LENR also. And/or there may be various resonant conditions caused
by electric or magnetic field manipulation that promote or "poison" the LENR.
Any of these parameters may affect the formation of the SPP population which I
believe is involved in the LENR intensity. I also believe there is a good heat
transfer mechanism operating in the Ni-Li-H-Al reactor that promotes fairly
uniform temperature profiles and hence resonant lattice vibrations and LENR. I
think spin energy manipulation of the nano system of atoms and transmutations
to lower energy states is the ultimate source of energy in these reactors.
This feature is what keeps the hard gamma radiation down with small changes in
the nano system energy states and no hot kinetic particles.
Who knows? These are merely guesses. Temperature seems to be the main
controlling parameter--at least one that the people who understand the LENR
mechanism talk about and reveal. The recent Russian experiment also seems to
point to the controlling nature of the temperature. However, resonant RF
signals may also be important in the Russian experiment and are used to control
it. A separate RF noise generator could be used to shut down a reaction by
interfering with the resonant conditions. The heater coil windings may act as
a source of non-resonant or resonant RF, for example.
As Bob Higgins pointed out, the Russian experiment uses a ribbon type wire
wound around the reactor with a gap in the middle where the windings appear to
be further apart. This design seems strange and must have a purpose. The
apparent non-univorm heating of the reactor along its length may reflect this
winding configuration. It may also promote a RF pattern within the reactor
that is necessary for resonances to occur.
Again, who knows.
Bob
----- Original Message -----
From: David Roberson
To: [email protected]
Sent: Friday, January 16, 2015 7:23 AM
Subject: Re: EXTERNAL: [Vo]:TRISO LENR pellet
Thanks Bob,
You have offered an educated description of some of the more intricate inner
behavior of a light water fission reactor. I had been previously introduced to
some of the processes at work but your input is much more of the type that
engineers understand. It is always refreshing to be exposed to the real life
secondary considerations that result in modifications to the original less
sophisticated designs.
I find your information concerning the cooling factors quite interesting and
demonstrates that where a problem exists a solution can be found. Perhaps a
pile of Axil pellets would not work due to the very same issues that you
discuss as applying to nuclear reactors, whereas a well engineered geometry
should lead to a successful design.
Dave
-----Original Message-----
From: Bob Cook <[email protected]>
To: vortex-l <[email protected]>
Sent: Fri, Jan 16, 2015 4:40 am
Subject: Re: EXTERNAL: [Vo]:TRISO LENR pellet
Dave--To answer your question about reactor control I offer the following:
Light water fission reactors using U-235, U-233, and Pu-239 fissionable
isotopes depend on thermal or relatively slow neutrons to react with those
isotopes. The slower the neutron the more likely it will be absorbed by one of
these isotopes and cause it to fission. Each fission produces more neutrons at
high energies that are slowed down by collisions with water and other material
in the reactor until they are thermalized--at an average energy determined by
the temperature of the reactor. At criticality the population of neutrons is
steady with as many being produced as are leaking out of the reactor (not to
enter the fuel region again) or being absorbed by materials such as control
rods. More power is produced as the temperature is decreased because the
average energy of the population of neutrons is reduced and the interaction
rate with the fissile isotopes in the reactor is increased. If the power
generated is not extracted from the circulating coolant the temperature goes up
and the reaction rate (fission rate) goes down on average because the energy
spectrum of the neutrons is higher. This is a negative feed back called a
negative temperature coeff. and is an inherent control feature of the power in
the reactor. However if the water is cooled again the power increases and
holds the reactor at a selected average operating temperature. Heat extracted
from the primary coolant of the reactor by a steam generator is such a cooling
mechanism for the primary coolant.
The fissile isotopes also react with faster neutrons at various energies,
however at lower probability than they do with the thermal neutrons. Thus,
they there are many fewer fissions caused by fast neutrons before they are
thermalized in the reactor during normal reactor critical operation. However,
with a rapid addition of neutron population, power can drastically increase at
a high rate and cause a large increase of fast neutron compared to the thermal
neutron population. If this happens a condition of "prompt criticality" can
occur and the reactor can explode because of a high energy production rate.
Reactors are designed to add a poison--a control rod--to absorb neutrons if
the rate of production--the rate of population increase--is too high. Such
control rod action avoids prompt criticality.
An accident called a cold water accident can occur in reactors which adds a
slug of cold water to the reactor and causes prompt criticality before the
control rod system has a chance to add poison. This must be avoided to keep the
reactor in tact.
The various assemblies in a core produce differing amounts of power with the
colder regions near the entering coolant producing more power than the hotter
regions. Thus at higher powers the differential temperature across the core is
greater given a constant coolant flow rate. To keep the temperatures in a core
closer to an average temperature the flow is increased as more power is
generated. Fuel assemblies are loaded with differing amounts of fissile
material depending upon the location of the fuel assembly in the core with
higher loading in radial positions that may have a lower neutron population on
average. The fuel design objective is generally to create a system with even
power generation throughout the core. Such a condition can only be approached
in practice and changes as fuel is depleted with operation.
Most modern reactors include burnable poisons--for example boron--that are
depleted as the same time the fuel is depleted. This reduction of the poison
in the fuel allows an increasing thermal neutron population inside the fuel
element and thus maintains an more constant fission rate with time as the local
fissile isotopes decrease.
Bob
----- Original Message -----
From: David Roberson
To: [email protected]
Sent: Thursday, January 15, 2015 2:41 PM
Subject: Re: EXTERNAL: [Vo]:TRISO LENR pellet
You make a good point Robin. My concept is to make one pebble first that
has the characteristic that you wish and then to work on the complete system of
them to end up with a good overall plan. For instance, if a coolant is flowing
through a large number of them, it will extract heat from the group. I suspect
that the geometry of the complete system can be played with so that all of them
contribute to the net heat being extracted. This may require that coolant be
injected along the container sides or other structures so that none of the
pellets is over stressed.
I would not think that a big random pile of these devices would work
properly due to problems with heat generation and extraction, but a good
engineering plan should be able to solve the problems. I would assume that a
nuclear reactor would face similar issues with their multiple fuel rod
assemblies yet they seem to be able to operate properly. Perhaps one of our
reactor experts can help with this issue.
I am discussing a design of this type in response to the pebble concept
mentioned by Axil. I am not biased either for or against that idea.
Dave
-----Original Message-----
From: mixent <[email protected]>
To: vortex-l <[email protected]>
Sent: Thu, Jan 15, 2015 4:15 pm
Subject: Re: EXTERNAL: [Vo]:TRISO LENR pellet
In reply to David Roberson's message of Thu, 15 Jan 2015 10:18:27 -0500:
Hi,
[snip]
>The amount of positive feedback can be adjusted by establishing the proper
ratio of sphere surface area to volume. As the pellet becomes larger the
surface area varies as the square of the radius. At the same time the volume
varies with the cube of the radius. In an ideal case that suggests that the
feedback ratio would vary directly with radius. If some form of insulating
material is coated upon the outer surface the fuel volume can be reduced
considerably.
>
Take into account that this is only valid for a single separate sphere. Once
they are all bundled together, heat leaving one will enter another, so in the
limit, the surface area is reduced to the external surface area of the
conglomeration.
Regards,
Robin van Spaandonk
http://rvanspaa.freehostia.com/project.html
