You know Axil, maybe they are based on the internal pressure estimates I've
read here.  When the MFMP finally had the pressure transducer stabilized
they had 100psi which decreased linearly to 0 after power off.   A redo of
that experiment would be worth doing just to get the kinks out of the
pressure gauge.  Then you might see the disassociation of LiAlH4 to Li and
H in the pressure change.  As another vortexian mentioned, I don't think
that has ever been published.  So knowing PV=nRT the value 'n' can be
deduced or the expected value of P can be deduced with temp as some have
already done.   Given a temperature goal, and perhaps knowing the strength
of the contain these can be designed into the experiment.  So instead of
worrying about seals, just design a tube that can contain hydrogen gas at
1400C and be loaded with fuel under a vacuum to maintain purity of the
reactants.


On Sat, Jan 3, 2015 at 11:29 PM, Axil Axil <[email protected]> wrote:

> I think that MFMP is concerned about melting or exploding the core.
>
> On Sat, Jan 3, 2015 at 11:07 PM, CB Sites <[email protected]> wrote:
>
>> I agree with you Bob.  Getting a good seal will be the challenge of this
>> experiment.   I've seen a few electron micrographs of hydrogen is Si and
>> other metals and it is amazing how deep H will migrate into a lattice.
>> Jones Benne points to the S-bond.com.   It will take something more than
>> that to seal this structure at the high temps, high pressure and
>> embrittlement from hydrogen gas in this experiment.    Knowing the pressure
>> and core temp is a noble cause, but until replication is done, do we know
>> enough about the phenomena to pursue those experiments?
>>
>>
>> On Sat, Jan 3, 2015 at 6:40 PM, Bob Cook <[email protected]> wrote:
>>
>>>  Jones--
>>>
>>> Unless the thermal expansion of the alumina body is matched to the
>>> expansion of the Stainless Steel sleeve, it will be very hard to maintain a
>>> seal.  The thermal stresses will become very high at the interface of the
>>> two materials. I think that the pressure changes seen in the recent MFMP
>>> test were due to thermal expansion acoustic emissions upon each increase in
>>> temperature.  This emission caused the pressure sensor to spike.   A sonic
>>> acoustic emission monitor would be valuable to deduce where the strain is
>>> and its intensity as a function of heating, if good sealing of the
>>> connection is necessary.  I am not sure the objectives of the test required
>>> such sealing and pressure containment.
>>>
>>> (Acoustic emission monitoring is an old technique to look for micro
>>> cracking in fission reactor equipment that happens during thermal
>>> transients.  Its quite sensitive and has/had been resisted by reactor
>>> vessel manufacturers, because it was so good for identifying defects in
>>> their forgings that other wise might not be discovered.)
>>>
>>> Bob
>>>
>>> ----- Original Message -----
>>> *From:* Jones Beene <[email protected]>
>>> *To:* [email protected]
>>> *Sent:* Saturday, January 03, 2015 1:49 PM
>>> *Subject:* [Vo]:Ceramic-to-metal hermetic bonding
>>>
>>>  It is possible to bond alumina, such as a modified dogbone reactor
>>> directly to stainless tubing, using the proprietary S-bond alloy :
>>>
>>>
>>>
>>> http://www.s-bond.com/blog/2011/04/04/ceramic-metal-bonding-part-one/
>>>
>>>
>>>
>>> The advantage would be allowing a permanent fill port for hydrogen,
>>> along with a pressure gauge, and other feed-thru accommodations which are
>>> more easily ported into metal then into ceramic.
>>>
>>>
>>>
>>> The design problem would be in keeping this metal part of the reactor
>>> cooler than the rest of the reactor – and the simple solution for that is
>>> to add a long ceramic extension tube to the dogbone, which extension is not
>>> powered and it can be as long as the reactor itself with a decreasing
>>> temperature gradient, then to add the stainless plumbing to the far end of
>>> the ceramic extension tube using S-bond. This keeps the heated segment
>>> spatially removed from the stainless. There would be a hot-end and a
>>> cold-end, and the entire unit would be much longer.
>>>
>>>
>>>
>>> For any dogbone device to move towards commercialization, far more
>>> control must be implemented, including fuel availability and pressure – and
>>> this means adding hydrogen from a tank at a controlled pressure. A ceramic
>>> to metal bond is one way to do that.
>>>
>>>
>>>
>>> I am assuming that hydrogen is the only consumable, at least until
>>> testing from Parkhomov shows otherwise.
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
>

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