Dear Jonathan The video you sent shows a TLUD gasifier with a 'bluff body' in the combustion zone. The reason you find it helpful is the same reason the 'concentrator disk' is used. It helps maintain the flame when disturbed or uneven in any manner. As a flame is self-disturbing they always assist. There are many variations on the theme. They all work.
There are other ways to use the function provided by a bluff body. I have used a central one with a circular space around it, spraying paraffin at the middle of the disk and using the bluff body as a flame retaining impediment to gas and air flow. The advantage of such a system is that when the central disk is removed (falls off because the stove tips over) the fire self-extinguishes immediately. I found out today that gas water heaters that have concentric direct intake and vent pipes (no fan on the exhaust). When the pipe is less than 30 inches long, a bluff body is placed across the vent to create a slight back-pressure to stabilise the natural gas flame. It is no more than a rectangular strip and two screws. If you were to reduce the amount of secondary air I think your can stove would have a more stable flame. It runs at a very low power and would benefit from a small air supply. This sort of thing is very difficult to tune precisely without a combustion analyser because you need to watch the CO/CO2 ratio while reducing the air, to the point where the CO/CO2 ratio starts to increase. There is no magic number to seek - I find all sorts of inflection points. You can, without any instruments, tweak the air closed until your eyes water when placed in the gas stream. Eyes are pretty sensitive! It has a lot (or everything) to do with the layout of the parts. Thanks for sharing Crispin Subject: iCan w/ Deflectors @ 20 minutes Flame action in combustion zone _______________________________________________ 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/
