[Stoves] Malot-blower

[frank]

Martin, Frans and stovers,

You were right about my thinking in terms of a propeller-type fan and 
must say I was confused as to why you didn't angle your blades to 
achieve one. Thanks to your explanation of how this type of Malot radio- 
blower works moving air from the center to the outside makes a lot of 
sense and puts me back to the drawing board armed with a lot more 
knowledge.

Can the shaft be hollow with holes between the fins in the center. One 
end of the shaft pocked out the bottom of a closed end pipe and the 
other sealed so air must suck into the shaft and out at the fins to 
finally blow air up the pipe? Something like that?

Boll, Martin Dr. wrote:

> Malot blower: Here theme-branched to / intermediate reflux of burning 
> gasses
>
> Frank,
>
> You think of the action of a propeller-type fan. Thereby the draft 
> moves in different directions, when driven by a bow. But this works 
> one to one in each direction. -But that is originally not my 
> intention. I t is simply to blow in one direction.
>
> I don’t think, it would be possible to drive such a “propeller”-fan 
> with a bow so fast, to get a usable blow. Out of that reason the 
> Malot-blower is a radial-blower, with the effect, that it blows always 
> from axle to peripheral area. Mostly that is good, but you do not want 
> this.
>
> So the new idea you have, inverting the draft in a T-LUD for a short 
> time will not work in the sense you thought.
>
> But there are two basic different methods to get nearly the 
> draft-inverting as you think:
>
> 1. If you block for a short time the off-gas of the T-LUD, the 
> creating process of burning gasses goes on. But if the way upwards is 
> blocked, the gasses steam downward, that is nearly what you want to reach.
>
Perhaps that will put out the secondary combustion? I am thinking the 
area between the primary and secondary will need to buffer the flow of 
pyrolysis gases to still have a steady outflow of gases to the secondary..

> 2. If you take a radial-rotor, which is heat-resistant, e.g. the 
> malot-rotor made of tubes and sheet-metal, you can put it into a tube 
> of which the bottom is closed. The rotor sucks then from the 
> shaft-near area (in this case from above) and blows to the periphery 
> of the rotor. By this you can get a suction downward through the grate 
> and a blow upward through the peripheral gap between the burning 
> chamber and the outer wall, in direction of the secondary-holes/jets. 
> In the time, when the rotor is not moved, there is normal natural draft.
>
> I think, between the central (sucking-) area and the peripheral 
> (blowing-) area, it will be best to separate by a metal-circle-plate 
> with a central hole. This central hole must not be too big, but big 
> enough to get the desired suck.
>
> 3. _/If !!/_ that would work, you could try to make a central hole on 
> the downside as well, which can be closed, but from size a lot bigger.
>
> When the hole on the bottom is open, the suction from down is more 
> easy (more effective), and the suction from above (trough the grate) 
> is possible not big enough to invert the natural upward 
> draft-direction. When the bottom-hole is open, the suction of 
> fresh-air is bigger.Then you have the normal T-LUD function with some 
> secondary-air-blow.
>
> 4. Possibly another idea will work better: If you would take on the 
> same shaft two (connected) rotors, separated by a sheet-metal, into an 
> upper and under section, the upper rotor served for the suction from 
> above, and the lower rotor served for the suction of fresh air from 
> under. There must be two slide-shutters one closing the centre against 
> the grate and the other between the two rotors. One of the shutters 
> must be closed while the other must be open.
>
Lots of great ideas above. Do you have pictures! : )

> Before creating complicated mechanisms, it would be helpful to know, 
> if tidal reverse air-flow would better the burn of a T-LUD. That would 
> spare a lot of work.
>
This is what I want to do but need to figure out a way to set of the lab 
equipment and way to change the air flow in a timely manner with the 
equipment I have available. (and the time!)

> Regards
>
> Martin
>
Thanks
Frank


-- 
Frank Shields
Soil Control Lab
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