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Volcano stove

Posted: Sun Mar 16, 2008 9:43 pm
by Tony
This is a design that I have been working on intermittently for a few months and I finally found time on the weekend to do some more development.

The volcano stove is based on the principals that larger the stove flame/pot ratio the more efficient the stove/pot system is, this is shown in my pot size/efficiency forum posting (http://bplite.com/viewtopic.php?f=25&t=556) and that slower heating is more efficient that fast boiling (fast boiling and efficiency with stoves is a myth that manufactures have perpetuated to sell stoves).

The cone top is to allow better air entrainment into the flame. The lip around the outside is for priming. The pin in the middle has the function of blocking the middle hole as well as transferring heat to the alcohol to aid vaporization and different size and mass pins can be used to adjust the flame strength. By this method I was able to tune the stove to improve its efficiency. The stove is still in the development or tuning stage and has shown very promising results. I have had efficiency figures of 70%. The stove as pictured weighs in at 6 grams 0.21 oz).

The volcano is made from the bases of two Red Bull cans with the top cone made by pressing between a specially made die. 8 x 1.3 mm hole are drilled in the top for jets and a 5 mm hole in the center for filling. The pin is machined from 6.35 mm aluninium bar.

The stove has only been tested on small diameter pots and so far has shown very good efficiency it also works very well with a JetBoil PCS pot that I modified. All of the small pot test have used less than 11.7g/80C (0.5 US fl oz/80C). I have not done large pot test yet but I expect some good results especially with the 1.5liter JetBoil GCS pot.

In the tests 0.5 liters of water was heated from between 20-25C to 95C and results extrapolated to get g/80C.

The best test result so far the volcano stove used 9.3 grams of denatured alcohol to heat 0.5 liters of water 80C and took 12 minutes. 9.3 grams = 11.77 mls = 0.4 US fluid ounces, in this test I used my modified 1liter JetBoil PCS pot. Of that 9.3 grams 0.55 grams (0.7mls) was used in priming.

Tony

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Re: Volcano stove

Posted: Sun Mar 16, 2008 10:45 pm
by Allen
Thanks for posting the pictures, Tony :)

Really nice design!

I appreciate Your emphasis on efficiency.

The potstand shown in the third photograph is very interesting.

Cheers!

Re: Volcano stove

Posted: Sun Mar 16, 2008 11:07 pm
by Tony
Hi Allen

The pot stand is a special invisible anti gravity one that I am developing, I was hoping that nobody would see it.

It has the advantage that I can adjust height(picture below)

Tony

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Re: Volcano stove

Posted: Sun Mar 16, 2008 11:23 pm
by Allen
What a great idea, Tony!

Every test bench should have one :D

Cheers!

Re: Volcano stove

Posted: Mon Mar 17, 2008 5:54 pm
by Ridgerunner
The pot stand is a special invisible anti gravity one that I am developing, I was hoping that nobody would see it.

It has the advantage that I can adjust height(picture below)
Great idea for finding peak performance in determining potstand height. Good work on the efficiency side. Always enjoy your input, Tony. Thanks ! ;)

Re: Volcano stove

Posted: Mon Mar 17, 2008 6:32 pm
by zelph
Very interesting Tony. We look forward to more test results.

I've tested a burner that was designed to burn slow and and it would boil 2 cups under ideal conditions in 11 min. using 1/2 ounce denatured. Once the ideal conditions were tampered with the burner was not able to acheive the boil. The slightest breeze made such a difference. Heat loss compared to heat gain gets to the point of teeter tottering. I'm lead to beleive there is a fine line when using burners with the small flame design. You're stressing pot/burner to be matched to each other. I can see that being very important. The matched set is the ultimate goal, nice project Tony!!! I'll be following your results.

Re: Volcano stove

Posted: Fri Apr 04, 2008 7:03 pm
by DaddyMnM
Wow, Tony. I'm glad I took at look at this one. Then pin idea is clever. Do you notice enough of a difference between pin sizes to provide both a low and a high option or are you just tuning for one optimal design?

Re: Volcano stove

Posted: Sun Apr 06, 2008 5:59 pm
by Tony
Hi DaddyMnM,

Sorry about not replying earlier but I have been away walking/fishing for the weekend.
Wow, Tony. I'm glad I took at look at this one. Then pin idea is clever. Do you notice enough of a difference between pin sizes to provide both a low and a high option or are you just tuning for one optimal design?
With different size pins I have noticed big difference in boil times 6 minutes to 12 minutes with the latter using slightly less fuel. I hope to be able to make the stove simmer but I am still working on the developing other parts the volcano stove, I have a smaller model working very well and I have one stove pin combination that can boil 500-ml (2.1US cups) of water in about 6 minutes using less than 10g, 12.6 mL (0.43 Us fl oz) of Australian denatured alcohol (95% ethyl alcohol), I am currently working on a larger stove that can boil 1l of water and then can simmer for a few minutes but all that takes time and I have a few other projects going on at the moment.

Tony

Re: Volcano stove

Posted: Sun Apr 06, 2008 8:51 pm
by DaddyMnM
Hey Tony,
Don't sweat the delay in answering. Getting out is what it's all about. I think that design you are working is pretty sweet. It's interesting to see how a few simple ideas can make such a difference.
Thanks for Sharing.

Re: Volcano stove

Posted: Mon Apr 07, 2008 2:10 am
by Tony
Hi DaddyMnM,

Thanks for your interest, I am new to alcohol stove building but I have been playing around with canister stoves for a few years now, here are some url’s to some postings of my canister stove creations. http://bplite.com/viewtopic.php?f=19&t=402 & http://bplite.com/viewtopic.php?f=19&t= ... &sk=t&sd=a

I also have a reasonably hi tech stove testing setup at home, soon to become even better.

I have read that you are active on a few other sites, I am always interested in what other stove makers are doing and would be interested in looking at some of your ideas.

Tony