[Stoves] Very small stoves and reheating food

[Alex English]

On 24/10/2012 4:56 AM, Crispin Pemberton-Pigott wrote:
>
> Dear Alex
>
Crispin,
>
> I get ?3 kW for that burn rate. Is that correct? Ideal for single pot 
> cooking.
>
That is close to a minimum, so not ideal for focused single pot cooking. 
Works well for heating and cooking together.
>
> To develop your comment to Richard about the air flow, cover or not, I 
> understand from Tom Reed that the superficial velocity is the marker 
> for a fire occurring systematically in the hopper or not. If the air 
> flow through the fuel is above some limit, the heat will not rise in 
> the hopper. Yes?
>
Pellets allow for a very even or consistent flow of air with no 
channeling. This does cool the pellets but at this SV (superficial 
velocity), without the concurrent pellet flow, the fire would creep up 
into the fuel supply, towards the air. I suppose there is an SV that 
would extinguish the fire. The pressure drop across the fuel at this 
burn rate is around 0.02"WC.
It may not change much at higher burn rates. There are four air 
introductions, under chimney 'suction' if one is changed the others also 
change. I use a funnel in funnel approach which limits the pellet column 
depth for pressure drop and allows a much larger bin above. This also 
buts a brake on thermal conductivity through the structures. The larger 
bin could have a sealing lid. In fact I use a lid to reduce  air flow, 
SV, when burning wood chips.

I like SV because it allows me to throw around technical terms 
superficially and not include numbers:)


Alex

> Regards
>
> Crispin
>
> **
>
>

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