Aluminium powder and Fe2O3 may give lots of heat in short time a
termite reaction. 

Have you any calculations about how much energy this
reaction may release? 

On Tue, 17 Mar 2015 18:26:24 -0400, Axil Axil 

Steady accumulation of energy followed by its rapid release
can result in the delivery of a larger amount of instantaneous power
over a shorter period of time (although the total energy is the same).
Energy is typically stored within a circuit of the device. What happens
is based on the circuit of the dimmer.  

By releasing the stored energy
over a very short interval (a process that is called energy
compression), a huge amount of peak power can be delivered to a load.
For example, if one joule of energy is stored within a capacitor and
then evenly released to a load over one second, the peak power delivered
to the load would only be 1 watt. However, if all of the stored energy
were released within one microsecond, the peak power would be one
megawatt, a million times greater.  

If the current rise is fast
enough, the wire does not have enough time to heat up, but the magnetic
flux during the rise might be huge.  

On Tue, Mar 17, 2015 at 6:09 PM,
David L. Babcock  wrote:

"Very sharp" -just means that the power is
applied nearly instantaneously. Not any more power, just whatever equals
E2 /R. However the temperature gradient would indeed be higher, so the
wire would expand sooner than the matrix around. If the matrix
temperature rises and falls a lot during a small part of a line cycle,
stress might get pretty high. But isn't the wire a near-zero
expansion/temperature material?

 Ol' Bab -who was an engineer... 

3/17/2015 4:02 PM, Axil Axil wrote:  
In these triac light dimmers, the
rise/fall times are very sharp maybe in the nanoseconds. That means that
a lot of instantaneous power is being feed into the heater wire as the
power pulse starts when the leading edge waveform is used. 

On Tue, Mar
17, 2015 at 4:56 PM, Axil Axil  wrote:

According to Jack, the reaction
did not happen in the fuel, but in the insolating layer. The fuel
composition does not matter. IMHP, what matters is the exact nature of
the heater current. 

On Tue, Mar 17, 2015 at 4:38 PM, Robert Ellefson 


Fantastic! I'm really stoked to hear of your progress. I
think your powder recipe sounds very interesting, and I would love to
know more about the details of the reactants. It sounds like you've come
up with a mixture which may contain one or more key ingredients not yet
identified as being of primary significance to the high-gain modes of
these systems.  

If I may fire away: 

What size Fe2O3 and TiH2 grains
were present?  

Is this mixture generally not hygroscopic, and
therefore is curing the reactor's sealant a simple matter as compared to
 Are you tumbling or milling these reactants, or performing any
other notable processing steps, prior to putting them into the reactors?

Thanks for sharing, and keep up the great work! 


FROM: Jack
Cole [ [4]] 
SENT: Tuesday, March 17, 2015 1:08
TO: [5] 

SUBJECT: Re: [Vo]:melted alumina tube  


The input power was ~260W. I don't know what the R value of
the insulation is. I had the cell surrounded by high purity alumina
powder and covered with a thin sheet of ceramic insulation. I used
standard 120V AC 60hz with a triac type dimmer switch (chops the waves
starting at V=0). I'll have to check with the manufacturer to see what
the remaining 5% of the tube is. The heating element was Kanthal A1.
It's strange that the heating element was able to completely melt at
points. In the past, it has always failed before melting.  

I was using
INCO type 255 nickel, TiH2, LiOh, KOH, aluminum powder, and Fe2O3. Good
idea on the small amount of fuel which should cause some localized

The fact that the fuel was a small diameter cylinder seems
to suggest that it was fully expanded in the tube and shrunk down. 


On Tue, Mar 17, 2015 at 2:02 PM, Bob Cook  wrote:  


It looks like you had a pretty good reaction.   

What was the input
power? What is the R value of the insulation on the outside of the
electric coils? What was the nature of the electrical input--frequency
etc? And what is the electrical heating element material? If you have an
acetylene torch, see if you can melt a piece of the tube that melted.  

The tube may have had glass fibers incorporated in order to improve
strength. You indicated it was 95% pure. What was the other 5%?   

was you fuel mixture? You may want to try a small fuel loading and see
if the same intense reaction happens--all else the same.   

Try the
test with a iron core instead of a fuel load and determine if there is
an apparent magnetic field which would hold the iron core in position
when direct current is applied to the heating coil. An alternating
current would of course change the magnetic field and may make for null
reaction conditions.   

 Try 2 or 3 t/c's if you can--one inside and
two outside to get a measure of the temperature gradient along the tube.
Also another easy way to determine temperatures is the use of thermal
sticks on accessible surfaces. Welders use these to determine preheating
temperatures. They may provide a cheap temperature measure for you.  

Keep it shielded--good luck.   


----- Original Message ----- 

FROM: Jack Cole [7]   

TO: [8]   

Tuesday, March 17, 2015 9:39 AM  

SUBJECT: Re: [Vo]:melted alumina tube

To add a couple of more details. The agglomerated piece of material
is extremely hard. I tried to break it off with pliers, but it seemed
like it would take more force than to break the entire cell. The
resistance wire is extremely difficult to separate from the cell. I plan
to open the cell with a diamond blade later today to see if more can be
learned about what took place (e.g., evidence of melting on the inside
of tube). I was able to get one piece of the resistance wire pried from
the tube. There were indentations in the cell.  

As a follow-up
experiment, I need to run it without the fuel to the same power levels
to see if the same effects occur.   

On Tue, Mar 17, 2015 at 9:42 AM,
Jack Cole  wrote:  

I had an interesting experiment yesterday. This was
my first time using a triac to regulate input power and sealing the tube
with a compression fitting. Unfortunately, my thermocouple failed. 

Take a look at the alumina tube and the evidence for melting. The
furnace sealant which I coated it with completely melted and
agglomerated to the bottom of the cell (also appears to be mixed with
melted alumina).

The tube was purchased from China and is purportedly 95% pure.
It was supposed to have a continuous operating temperature of 1500C.  

Any opinions?  




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