[Stoves] Gas Sensing

[Crispin Pemberton-Pigott]

Dear Lanny

You might be better off being able to switch the accumulation of gases onto
the room or not.  By that I mean if you can get a stove running and then
when you are happy it is going well, direct the fumes into the room for a
period of time.  Then you can measure the gases produced by burning a known
mass of fuel, for example, or a measured time period.

There are a lot of fumes produced by a stove operating for an hour. I think
Dean's point was to try to have a known flow rate into and out of the room
so that the production of fumes could be quantified.

Gunter Helas from the Max Planck Institute showed me yesterday how they are
using a 20 foot container as an accumulator and 'averager' of gases to get a
pretty smooth data set. They are also having a measured amount of air enter
the system so they can calculate things based on the turnover.

Incidentally Gunter had a number of interesting to say about emission
measurements which I will try to report on when the topics arise.

If you remember my pointing out the NO and NOx levels measured with the
combustion analyser at ETHOS, Gunter showed me a slide of NO production that
did _not_ originate from within the fuel and there is nearly none until the
flame temperature went over 700 C at which time there is a large leap.  I
was pointing out to the participants that something about the maximum flame
temperature can be noted from the NO level without actually making a
temperature measurement.  Gunter sez: it tells you if some of the flame is
over 700 C (and not much else).

Regards
Crispin in Boksburg