[Stoves] ***SPAM*** Re: Testing with wet wood

[neiltm at uwclub.net]

On 30 Jul 2022 at 2:05, Ashok Mathur wrote:

> Dear DaleWhen you burn wet wood, you going to use the energy within the
> wood to make the water evaporate.Say ten percent wet wood will mean that
> ten percent of weight will be water that will require it be converted into
> steam. As latent heat of evaporation is huge, fuel efficiency will come
> down by magnitudes.So donTMt use wet wood to burn a fire.Ashok

What if you only have wet wood because you live somewhere that rains 
a lot?  I have successfully boiled water in a volcano kettle in the 
rain with sticks that were literally dripping, carefully conserving a 
finite stash of dry wood to start the fire and build up the heat so 
that the energy in the wet sticks would be fully liberated despite 
the losses involved in driving off the moisture.

Then there is the usefulness of moister wood where stove design is 
fixed, with no air control, or with an open fire, for varying the 
heat.   With my natural draught TLUDs I often place a damp layer in 
the bottom to avoid the flare up at the end of the pyrolysis, when 
greater heat is least wanted, and thereby also extend the burn.  With 
experience, such layering can produce a bring to the boil, then 
simmer phase in a fixed draught stove from varying the fuel alone.

Where drying fuel may be problematic in the open air sometimes, 
utilising the heat of the fire to do the job may still be arranged in 
such a way as to take advantage of the moisture for 'turn down', or 
simply continuity of supply under difficult weather conditions.  Some 
woods even burn well green, like Ash.

I appreciate that where fuel is scarce and dry, and wet wood easily 
avoidable or even unavailable, your admonition is relevant, and where 
appropriate stove design for the dry fuel is paramount.

For my uses in my climate I have settled on the volcano kettle for 
water boiling, and the cheap stainless steel Chinese ND TLUDs found 
on ebay.  These are optimised to burn wood as most often commonly 
found in europe and N America at least - less than completely dry, 
making them always useful where dry wood may be hard to find.  With 
completely dry wood they produce a flare that may last 10 minutes at 
the most, which is also great for stir fry of course.

I started out with the Reed FD TLUD 'woodgas camp stoves', which were 
great, but far more fuel fussy, being optimised to burn dry wood 
which they did very well and much more cleanly than the stoves I use 
now.  But in the contest between clean pan bottoms and having a 
useful cook fire at all, the dirtier simpler stoves win I'm afraid, 
and a bit of soot is easily dealt with.  A small volcano kettle is, 
quite accidentally also a perfect perch fit on them after the cooking 
for coffee and washing up.  Lift off the pan support/concentrator 
ring and plonk it on and chuck a couple of sticks or so in after it.  
So easy.  So many ways.

Neil Taylor (in a rarer tinder dry England at the moment)