[Default] On Wed, 10 Oct 2012 12:02:41 -0500,Paul Anderson <[email protected]> wrote:
>Dear Stovers, > >I do not know how to convert thermal efficiency into fuel savings figures. > >I hope it Is a linear transformation. 10% TE wastes 90% of fuel, >while 40% TE wastes only 60%? But I suspect it is more complicated >than that. > I hope Kevin's answer didn't confuse you as much as it confused me! If we take the efficiency figures as being correct and that they are a measure of how much of the fuel energy liberated is delivered into the pot then a 15% efficient 3 stone fire will burn 3.7 times as much fuel to do the job compared with a very good stove with 55% efficiency. At these higher levels of efficiency the heat exchange interface with the pot will be more significant then the completeness of combustion. Given that the mass flow through the stove and above the pot should be the same then a quick calculation using the temperature just above the flame and at the exit from the pot will give a relative figure for heat exchange; the ratio of heat supplied to heat rejected. Note at higher efficiencies this will decrease more noticeably as the pot gets hot because heat transfers to the pot depends on delta T between the hot gas and the pot contents. AJH _______________________________________________ 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/
