Ni-H workshop for experimenters.

  • Russ is our data collector. If you can help I'll ask him to get in touch. Right now he might be too busy to ask for help- but we shall see.

    Just let me know what your challenge / requirement looks like. I am fairly good with Excel. You can drop me a private message, if you like.

  • I should be more careful in the future to not prepare a future cancer :)

    What i can add: fuel was compact but with big dead volume ( shongsheng spirit) , things were heated by 2 concentric coils , to have a choice between full magnetism or not. In this case, full magnetism configuration was choosen. We heat with low volt level..and minimum number of wires ( magnetism).

    Next runs should add more understanding

    Therefore stay humble :)

    I don't know if at the 1100 degree mentioned earlier you had already excess heat.

    My feeling, for what it is worth is that after you reach excess heat at the desired temperature you should heat without the magnetic field applied.

    It might possibly prevent a meltdown

  • I don't know if at the 1100 degree mentioned earlier you had already excess heat.

    My feeling, for what it is worth is that after you reach excess heat at the desired temperature you should heat without the magnetic field applied.

    It might possibly prevent a meltdown

    I don't know if at the 1100 degree mentioned earlier you had already excess heat. NO

    Magnetic field is generated by the two concentric heating coils.

    Another time, with another colleague, temperature went from 350 ° to 650 ° in 4s, this time magnetic field was practically zero unfortunally a piece broke.

  • Another time, with another colleague, temperature went from 350 ° to 650 ° in 4s, this time magnetic field was practically zero unfortunally a piece broke.


    That's the way these systems behave at times. And generally something breaks when it happens. I suspect that the 600 degrees you measured was actually over 1000C inside the fuel tube- heat moves too slowly to cope with recording a quick runaway.

  • That's the way these systems behave at times. And generally something breaks when it happens. I suspect that the 600 degrees you measured was actually over 1000C inside the fuel tube- heat moves too slowly to cope with recording a quick runaway.


    Is that a reason to have also an internal thermocouple ?

  • Is that a reason to have also an internal thermocouple ?

    Several years ago I did some simulated excess heat experiments with hot tubes, using 50 W J Type bulbs to simulate the internal heat source. The tubes at that time were about 700-1300 W designs, roughly the size of the Lugano ribbed area (15-20 cm long, 1.5 to 2.5 cm OD). Tube breakage resulted almost every time. (The tubes were open on one end, so they did not burst violently, which they might have if sealed). Slow heat increases were manageable, but rapid ones were destructive.


    During the failure of the Cylinder 1, where a coil hot spot formed, the internal thermocouple showed only a slight bump in temperatures because the hot spot was about 1.5 cm from the thermocouple. The hot spot was visually about 300 C hotter than the rest of the tube on the outside. (I think I have IR data for the hot spot). So the internal thermocouple should capture a heat excursion if the effect is nearby, equally distributed along the tube core, or if the thermal conductivity of the tube is very high, but could miss it if extra heat is localized.


    Localized heat excursions are bad for tubes. Heat excursions that exceed the thermal conductivity of the tube by a significant amount are bad for the tubes.

  • I put a TC inside fuel tube, because i have to consider too ideas from my colleagues, because fashion concept also..

    However, from my understanding about accumulation charges we saw , it should be may be better to avoid to link the fuel with the ground..?

    Someone would have suggestions, about it?

  • I put a TC inside fuel tube, because i have to consider too ideas from my colleagues, because fashion concept also..

    However, from my understanding about accumulation charges we saw , it should be may be better to avoid to link the fuel with the ground..?

    Someone would have suggestions, about it?


    You can indeed put one inside the fuel tube- but your magnetic fields might screw it a little by inducing a little extra voltage. I never thought about the grounding thing, though it is perhaps logical that one should avoid it. Since we always use quartz or alumina fuel-tubes with thermocouple strapped directly to the outside surface we haven't had to consider it. The reason we don't put thermocouples directly inside is much simpler- we would effectively be adding more materials to the fuel and they could affect the results. Also we use $80 Omega Inconel-sheathed S-type TC's which survive for multiple fuel tests - if they were sealed into the tube we would -to a certain extent - be writing them off when the tube was put aside- either that or breaking them out and thus destroying the tube.

  • When I was working with high voltage electronics, I used USB isolators to make sure that any arcing to the USB-connected electronics would not damage the computer or scope. You might measure temperature through a DAC with floating power supply, and connect it to the logging computer through a USB isolator. That would prevent grounding the fuel through the thermocouple.

  • We do that when required. Both my colleague and I hold ham radio licenses, so are familiar with blocking and diverting spurious signals. But thanks for raising the issue, others may not be aware of the possibilities.

    By your exchange, we saw 2 things, first one is TC problems as described by Alan, next shall we ground fuel or not ?

    As i said earlier , we saw charges accumulation in case of metal vessels , probably we should take this into account.

  • Interestingly enough knowledgable people who handled Rossi's 'used' dogbones have told me that the ones which worked (not all did of course) would bear a strong static charge when cold for weeks after they had been set aside- that feeling of 'crackling' you get when wearing the wrong kind of clothes in a dry climate. So it may be that 'charge conservation' is an important aspect of some systems, and direct earthing should be avoided. We have not experienced this 'crackle' with our own alumina or quartz fuel-tubes having very close but external (and earthed) TC's, but maybe we just have not looked closely enough.

  • Interestingly enough knowledgable people who handled Rossi's 'used' dogbones have told me that the ones which worked (not all did of course) would bear a strong static charge when cold for weeks after they had been set aside- that feeling of 'crackling' you get when wearing the wrong kind of clothes in a dry climate. So it may be that 'charge conservation' is an important aspect of some systems, and direct earthing should be avoided. We have not experienced this 'crackle' with our own alumina or quartz fuel-tubes having very close but external (and earthed) TC's, but maybe we just have not looked closely enough.

    Dear Alan, as yourself we are in the "same boat"( french expression) so have to find money to see the next step :-)

    As well as we can't share publicly everythings we know...

    At the beginning, I built a big reactor sized as Ecat Ht with 120 ° heaters, unlike other replicators.

    Ideas of the time, were those of Me356 therefore runs after runs, things got brighter.

    During an event where in 4s temperature climbed up to 650° from 350°, i heard clearly large crunches.

    We stopped because reactor was plugged by H2 bottle so a ring broke because pressure has risen very high too.

    Simon brink is right, few LIOH amount inside LIH couldn't be too bad :-)

    i think for example, that Fe2O3 added by Rossi to his fuel remains simply an oxygen carrier to do that.

    Around 300° remains an area where a lot of experiments were successful for several teams, this is also where are far infrared, so mm wavelengh, so Thz :-)