Dear Friends When I clicked on the link to Paal stove project there was a random image that came up of a Protos vegetable oil stove. You can find it by looking at http://stoves.bioenergylists.org/en/node/1636
Have a look at the heating tube. It rises, coils a full turn then goes back down. In my experience boiling liquid fuels this should never be done this way and may explain why they have so much accumulation of the bio-gunk inside the pipe that needs to be cleaned out daily. Most interesting indeed. Is there something about vegetable oils that is fundamentally difference from paraffin that one would coil it like that? The pipe should always rise so that liquids and drops are always drained back to the source. If it does, you can get a balance between the evaporation heat needed (just enough) and largely prevent the decomposition of the fuel to the point where free carbon is available to condense onto the pipe. Interesting. I had not seen the inside before. Perhaps there is a completely different explanation for its orientation but that is just about a guarantee to create black deposits and bubbling. The problem is that in order to overcome the liquids/droplets problem, the temperature of the tube has to be much higher or it will sputter droplets which promotes the decomposition. At the higher temperature you get a lower tube life and decomposition, or at a lower you get sputtering. Is anyone else working on boiling liquid fuels for small stoves? Have you seen a similar layout and found it to work well? Regards Crispin _______________________________________________ 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/
