[Stoves] TLUD Oven paper updated

[Julien Winter]

Hi Marc;

Thanks for your paper on baking with a TLUD.  There is a lot we can learn
from your experience.

You have mentioned the problem with temperature control, and the solution:
turning down the primary air.

You have also mentioned a problem with duration of temperature, with about
2 hours being best.  Would you say that the solution to this is to build a
TLUD-oven unit that is designed to use only pellets as fuel, and use a TLUD
of sufficient depth to pyrolyze for two hours?  I find that 30 cm of
softwood pellets lasts about that long, and there is a slight reduction in
power output over time.  Otherwise, if using nut shells, would it be
possible to have a second TLUD to exchange with the first when pyrolysis is
complete?

You may be aware that measuring air temperature with a thermocouple is
prone to some inaccuracy due to radiant energy exchange between the
thermocouple and the environment.  In your case, since the walls of the
oven heat up, the error may not be of practical consequence ... but it is
something you may want to check into.

A radiation shield can be used to improve the accuracy of thermocouple
measurements in air.  I need to solve this problem myself.  At the moment,
I am considering inserting a K-type thermocouple probe into a thin-walled
stainless steel tube with openings at both ends, such as described here:
http://www.msm.cam.ac.uk/utc/thermocouple/pages/ThermocouplesInGasTurbines.html

Perhaps someone else has some suggestions?

Thanks again for the informative paper.

Cheers,
Julien.

(ps: Gmail's spelling checker has a sense of humor.  It wants to change
"pyrolyze" into "paralyze".  Good thing I did a little proof-reading.)

-- 
Julien Winter
Cobourg, ON, CANADA
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