Dear Crispin and stovers,
<snip>
If I ask for a maximum power of X and ask for a demonstration that it can be
controlled to X/4 is that reasonable as a minimum standard of proof?
Thanks
Crispin
The ability to cut off air or reduce fuel and still run at optimum with no
smoke is directly related to stove box shape, construction material, placement
of air and controls etc. Its something that if we can find one stove having a
good turn down ratio then we can get all stoves to do it. We need to find out
the physical properties that effect the movement of heat etc. This is the job
of the scientist going beyond the WBT. I see another ten step white paper …… :
)
Also;
Testing stoves to determine efficiencies is challenging due to the complexity
of how we are going about doing it. There are only two energy measurements
needed, Carbon and hydrogen (dry weight (dw)). We need to know the grams of
carbon and the grams of hydrogen (not water hydrogen) that we place into the
stove. How water effects the stove is in a group along with cold air, heat
transfer, utensil material etc. that drains heat from the task. Grams carbon X
0.3491 + grams Hydrogen X 1.1783 = HHV in kJ/g of fuel units is the energy
going into the stove. The Carbon and hydrogen (dw) left over after the Task is
energy not used. So ((CX0.3491)+(HX1.1783))-((CX0.3491)+(HX1.1783)) / task is
efficiency. I like the idea of measuring the solid materials. That is the fuel
going in and the left over material dragged out of the stove and watered and
oven dried when the task is completed. There are only the two elements to
measure, carbon and hydrogen. Carbon is easy but hydrogen is a challenge. We
have the $70k USD equipment that is a pain to use and includes lots of upkeep
and training. I suggest we *try very hard* to see if we can justify not
including hydrogen in the analysis. Or to estimate the hydrogen from the carbon
value or look up tables as good enough. Then we only have carbon to test and I
think there are simple ways we can come up with to do that.
Cellulose is 44% carbon and 6% hydrogen. That is 15.2 energy given for C and
only 7.07 for hydrogen
Char left over has < 1% hydrogen and 80+ % carbon.
If this seems like a good approach we need a simple and good carbon test.
Regards
Frank
Thanks
Frank Shields
BioChar Division
Control Laboratories, Inc.
42 Hangar Way
Watsonville, CE 95076
(831) 724-5422 tel
(81) 724-3188 fax
<mailto:[email protected]> [email protected]
www.controllabs.com
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