Crispin,
Ok, then now lets change the assumptions. Instead of assuming a constant
mass yield and energy loss to char, lets assume that that the low
temperature char has a higher mass and energy content. This would spread
the ratio. There are too few fact here, there, everywhere.... hear!
hear! When we go to low power on these TLUD we often go to higher excess
air and lower combustion and heat transfer efficiencies so the
impression is better turn down when in fact it is less power delivered
and worse quality turn-down. I have noticed shiney Tar deposits on pots
cooking on fan TLUDs at low firing rates.
It's still amazing how little we know of this religion. Clearly it moves
people. It moved me.
Unwavering :)
Alex
On 08/12/2012 11:03 PM, Crispin Pemberton-Pigott wrote:
Dear Alex
That is a power variation of about 1.5 : 1. If anyone can confirm similar
controllability for a ND gasifier we are onto something as a design focal point.
A practical stove for cooking needs sufficient power to bring pots of food to a
boil or maintain a stirfry wok on high. The turn down should be about 75% or so
allowing foods to be warmed without burning or carmelising everything. An
example on the bottom end of the power scale is the Panda paraffin stove which
is about 1100 Watts. It can be turned down to about 350. Perhaps Prof Lloyd at
CPUT can comment.
Alex, if the boil down entirely to air flow rate through the fuel, it seems
there are some practical limits on variability. Could perhaps it be switch from
char making to char burning modes (or something in between) in order to give a
greater range? I made a few stoves that will do that but they were burning
wood, not pellets.
Regards
Crispin in sunny SA
_______________________________________________
Stoves mailing list
to Send a Message to the list, use the email address
[email protected]
to UNSUBSCRIBE or Change your List Settings use the web page
http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
for more Biomass Cooking Stoves, News and Information see our web site:
http://www.bioenergylists.org/
_______________________________________________
Stoves mailing list
to Send a Message to the list, use the email address
[email protected]
to UNSUBSCRIBE or Change your List Settings use the web page
http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
for more Biomass Cooking Stoves, News and Information see our web site:
http://www.bioenergylists.org/
