[Stoves] Pot shells / Fin shells

[Lanny Henson]

Crispin,
I do not have that information. I did that 3 years ago.
Also I did not use my best burner.
I need to get back to that design it has potential.
Lanny
  ----- Original Message ----- 
  From: Crispin Pemberton-Pigott 
  To: 'Discussion of biomass cooking stoves' 
  Sent: Sunday, July 28, 2013 5:14 PM
  Subject: Re: [Stoves] Pot shells / Fin shells


  Dear Lanny

   

  The problem is the missing figure is the mass of fuel when the pot as boiled so I can't get an efficiency without making some (big) guesses.

   

  If the energy needed to simmer the rice for 30 minutes is 20% of the boiling energy, the system efficiency (which is the analogy of fuel efficiency) is 34%, conditioned on the following:

   

  If the charcoal remaining is useable in the next fire, it can be treated as 'unused fuel'. If you want an accurate figure, you would have to use this duel in a new fire and get the performance so that the amount of char remaining is the same as what you put in during that burn. 

   

  The 34% figure assumes the char is not burnable in the next fire.

   

  If it is (all of it) the system efficiency is 51% based on the simmering assumption.

   

  It should be remembered that the thermal efficiency should consider the thermal mass of the pot (mass x specific x change in temperature. If it does, the reported figure will be higher.

   

  Regards

  Crispin

   

   

  From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of Lanny Henson
  Sent: Sunday, July 28, 2013 3:37 PM
  To: Discussion of biomass cooking stoves
  Subject: Re: [Stoves] Pot shells / Fin shells

   

  Well I had 186 LB of water and rice, the rice was 50 lb. 

  Rice has a specific heat capacity of about .33 which is about the same as 16.5 of water so deduct 33.5 from 186 for a mass of about 152.5 lb water equivalent.

  I started with 15 LB. of wood and had 2.95 LB. left over = 12.05 LB. of wood used, and there was 1.5 LB. of charcoal left.

  The simmer time was about 30 min.

  The wrapper is 60" x and the vat is 48" long . I estimate the water was contacting about 36" of the 60" wrapper so the contact area was about 12 sq. ft.

  Does that give you the numbers you need?

  Lanny



------------------------------------------------------------------------------


  _______________________________________________
  Stoves mailing list

  to Send a Message to the list, use the email address
  stoves at lists.bioenergylists.org

  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://stoves.bioenergylists.org/

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/attachments/20130728/2cf31891/attachment.html>