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Galley alcohol, gas and diesel cookers/ovens

  • 18 Sep 2017 13:44
    Quote
    Reply # 5266001 on 5263270
    Deleted user
    Arne Kverneland wrote: Fans don't seem to do the job. They just make a disturbing wind. 

    I'm replacing "Fans" with "_______", and making this my new mantra for anything I see on the political news channels.
  • 16 Sep 2017 08:20
    Quote
    Reply # 5263270 on 5262985
    Anonymous member (Administrator)
    Annie Hill wrote:

    You can, of course, get little fans that run from dry cell batteries, but I doubt that they would suit.  I'm watching with interest.


    Fans don't seem to do the job. They just make a disturbing wind. The air jets from that initial test with a copper tube looked more promising. Now I have received the aquarium air-pump which hopefully will produce the necessary pressure. A good thing if this turns out to work, is that the setup doesn't require one to raise the pots higher on the stove. It can be used just like before.

    I hope to make a little test today.

    Arne

    Last modified: 18 Sep 2017 14:39 | Anonymous member (Administrator)
  • 15 Sep 2017 23:36
    Quote
    Reply # 5262985 on 1195343
    Anonymous member

    You can, of course, get little fans that run from dry cell batteries, but I doubt that they would suit.  I'm watching with interest.
  • 15 Sep 2017 05:12
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    Reply # 5261641 on 1195343
    Deleted user

    I should have known, a person has to get up pretty early in the morning to beat you to an idea Arne!  I look forward to hearing how the rest of your experiment goes.  
  • 14 Sep 2017 19:18
    Quote
    Reply # 5260973 on 1195343
    Anonymous member (Administrator)

    Darren,

    I too have tried to see if I could come up with an ‘unplugged’ device to mix more air into the flame. Most showed no improvement at all.

    The 18-blade ‘fan’, shown below was the only one which looked give a marginal improvement. Remember, that Trangia burner you pointed at on YouTube, already showed near-perfect combustion, so little extra improvement was needed. The un-treated flame of the Origo 3000 looks more like a yellow torch flame, so clearly needs a lot more air added.

    I have now ordered an aquarium air pump, rated at 2 x 180 litre/hour. I have no idea if that is sufficient capacity. That pump runs on 220Vac so I will use a little DC-AC inverter to feed it from the battery. The first test will be with the straight copper tube with five holes in it; the one I initially attached to the car tyre pump.

    Arne

      

    PS: The need for that inverter is not all bad: This can be helpful in driving and re-charging all sorts of small electronics, like the battery charger of the camera.


    Last modified: 16 Sep 2017 22:07 | Anonymous member (Administrator)
  • 10 Sep 2017 02:47
    Quote
    Reply # 5072590 on 1195343
    Deleted user

    I had similar ideas Arne and was inspired by some of the small DIY alcohol backpacking stoves that can be found readily with a youtube search.  Some work on similar principles to the Origo, while others use jets to create a vortex.  The models that are successful in creating a vortex seem to burn intensely with a clean blue flame.  I tried modifiying my Origo to add curved radial fins (imagine a squirrel fan) which would encourage the incoming air to form a vortex and thus mix more efficiently with the vaporized alcohol.  I was never successful, but I currently have way more projects than time and I only attempted trials for a couple of evenings before I abandoned the project for a Maxi stove.  If you could figure out a way to form a vortex with the incoming air, you might have a solution that didn't need to rely on electricity.  Here is one example using a Trangia stove, which has some similarity to the Origo.
  • 09 Sep 2017 10:12
    Quote
    Reply # 5071623 on 1195343
    Anonymous member (Administrator)

    David,

    yes, I'll see if I can get such an aquarium pump, which runs at 12V. My needs seem to fall between the fan and the pump. Meanwhile, i will try a 60mm fan I bought yesterday. Its static pressure is not high, but it has more air capacity. I will try this today, with the 1mm jets in that copper tube drilled up to 2mm.

    The fine, thing with this kind of mod, is that I will not destroy the original stove, and it can still work if the fan or the 12Volt fails.

    Arne.

    PS, 14.9.2017: That 60mm fan didn't work at all  -  way too low pressure.

    Last modified: 15 Sep 2017 08:45 | Anonymous member (Administrator)
  • 09 Sep 2017 09:25
    Quote
    Reply # 5071603 on 1195343
    Anonymous member

    You're on the right track, Arne. It's just as valid to pump jets of air into a cloud of vapour as it is to have a jet of vapour entering a cloud of air. In both cases, the aim is that the fast moving jet entrains and mixes with the other component. It's the same principle as the kerosene stoves that have a chimney consisting of two concentric perforated cylinders above a circular wick or trough, with combustion taking place in the gap between the cylinders.

    I think Paul's suggestion of an aquarium air pump is the right one. These are intended to pump air through a small tube under a little pressure, which is what you need.
  • 08 Sep 2017 02:56
    Quote
    Reply # 5069592 on 5069228
    Anonymous member
    Arne Kverneland wrote:

    Origo 3000 alcohol burner with air injection  -  an experiment.

    Any suggestion about that fan/air-pump?

    Arne

      


    A computer fan maybe or an aquarium pump? Or possibly a football bladder with a needle valve to control airflow? You'd pump it up just before use just like you do a pressure stove.

    BTW. I think you owe me an email :-)
  • 07 Sep 2017 23:51
    Quote
    Reply # 5069319 on 5069228
    Anonymous member
    Arne Kverneland wrote:

    Origo 3000 alcohol burner with air injection  -  an experiment.


    Any suggestion about that fan/air-pump?

    Arne

      


    I've used a 12V computer fan before, placed inside deck vents to create forced ventilation.  They are cheap and use milliamps of power.
       " ...there is nothing - absolutely nothing - half so much worth doing as simply messing about in junk-rigged boats" 
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