<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<div class="moz-cite-prefix">Marc and all,<br>
<br>
I am glad that we have the Brizer et al paper.
<blockquote type="cite">
<div><br>
</div>
<div>Birzer, C; Medwell, P; Wilkey, J; West, T; Higgins, M;
MacFarlane, G; Read, M. 2013. An analysis of combustion from
a top-lit up-draft (TLUD) cookstove. Journal of Humanitarian
Engineering, 2(1).
</div>
<div><a moz-do-not-send="true"
href="http://www.ewb.org.au/jhe/index.php/jhe/article/view/11"
target="_blank">http://www.ewb.org.au/jhe/index.php/jhe/article/view/11</a></div>
<div><br>
</div>
</blockquote>
It shows some serious testing. As a course project, these
students did better measurements than so many other more-casual
examinations of TLUD stoves. <br>
<br>
However, there are some differences between the academic and the
practical aspects. I am making observations, not criticisms or
compliments: [Also, if I have missed some point or incorrectly
cited something, please excuse me for replying after only a quick
re-reading.]<br>
<br>
1. The experimental TLUD was a single walled fuel canister.
(not what is being made in TLUD projects, with double walls.)<br>
<br>
2. The diameter is 200 mm (D = 8 inches), which is also uncommonly
large.<br>
<br>
3. The study of chimney heights were with chimneys equal to very
close to D [8"] and 1.5 x D [12 inches] and 2 x D [16 inches].
Interesting results. But there are no TLUDs that use RISERS or
Pre-pot chimneys greater than 0.5 x D. So the results are
interesting, but are not related to the practical aspects of
making TLUDs for household usage. <br>
<br>
4. A tall chimney can favorably impact the clean combustion of
the gases even if there is no concentrator. The other extreme,
being NO chimney, will be results of burning the gases at will at
the top of an open fuel chamber, and that will be with poor
emissions. Adding a concentrator with a short chimney has a
chance to have better (lower) emissions. <br>
<br>
5. I question whether or not 0.63 x D should be rounded up to
0.7 or rounded down to 0.6. Just an observation. But the
difference between 0.47 and 0.63 is not as noteworthy as between
0.5 and 0.7 when explaining the rather large difference in results
between the two sets of data and comparing to the 1.0 data set
that is similar to the 0.63 data set.<br>
<br>
I met these Australian researchers when they, while still
students, attend the CHAB Camp conducted by myself and Hugh
McLaughlin and Paul Taylor (in 2010). Great guys, eager
learners, keen to run experiments, and they completed what they
set out to do. I again say Congratulations. And Thank You.<br>
<br>
But they were doing just the start of what is needed, and what
could be done in university courses, and by the rest of us. To
over rely on their results and methods should not be the basis for
advancing TLUD (or any other) technology. Replicate, alter,
advance, and replicate again.<br>
<br>
Paul<br>
<pre class="moz-signature" cols="72">Doc / Dr TLUD / Prof. Paul S. Anderson, PhD
Email: <a class="moz-txt-link-abbreviated" href="mailto:psanders@ilstu.edu">psanders@ilstu.edu</a>
Skype: paultlud Phone: +1-309-452-7072
Website: <a class="moz-txt-link-abbreviated" href="http://www.drtlud.com">www.drtlud.com</a></pre>
On 8/29/2014 11:51 AM, Marquitusus wrote:<br>
</div>
<blockquote cite="mid:DUB127-W26AD464F13BB1B43C08658A8DB0@phx.gbl"
type="cite">
<style><!--
.hmmessage P
{
margin:0px;
padding:0px
}
body.hmmessage
{
font-size: 12pt;
font-family:Calibri
}
--></style>
<div dir="ltr">Dear Paul and others,<br>
<br>
Thanks for your comments.<br>
<br>
If you think the 0.7 diameter hole is not correct, what about
the other conclusions of this paper? for example, it says that
"the optimal chimney height is seen to be at 1,5D and a with of
D" (D = diameter of the burning chamber)<br>
<br>
Marc<br>
<br>
<div>
<hr id="stopSpelling">Date: Fri, 29 Aug 2014 10:00:21 +0800<br>
From: <a class="moz-txt-link-abbreviated" href="mailto:crispinpigott@outlook.com">crispinpigott@outlook.com</a><br>
To: <a class="moz-txt-link-abbreviated" href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a><br>
Subject: Re: [Stoves] Trying new burner for TLUD's<br>
<br>
<div style="width:100%;font-size:initial;font-family:Calibri,
'Slate Pro', sans-serif;color:rgb(31, 73,
125);text-align:initial;background-color:rgb(255, 255,
255);">
"<span style="line-height:initial;">Anyone knows any other
works on this aspect"</span></div>
<div style="width:100%;font-size:initial;font-family:Calibri,
'Slate Pro', sans-serif;color:rgb(31, 73,
125);text-align:initial;background-color:rgb(255, 255,
255);">
<br style="display:initial;">
</div>
<div style="font-size:initial;font-family:Calibri, 'Slate
Pro', sans-serif;color:rgb(31, 73,
125);text-align:initial;background-color:rgb(255, 255,
255);">
(circle of flame)</div>
<div style="font-size:initial;font-family:Calibri, 'Slate
Pro', sans-serif;color:rgb(31, 73,
125);text-align:initial;background-color:rgb(255, 255,
255);">
<br>
</div>
<div style="font-size:initial;font-family:Calibri, 'Slate
Pro', sans-serif;color:rgb(31, 73,
125);text-align:initial;background-color:rgb(255, 255,
255);">
Dear Paul<br>
<br>
</div>
<div style="font-size:initial;font-family:Calibri, 'Slate
Pro', sans-serif;color:rgb(31, 73,
125);text-align:initial;background-color:rgb(255, 255,
255);">
I think that is exactly what Gus was doing. We had a
discussion about it a couple of months ago. </div>
<div style="font-size:initial;font-family:Calibri, 'Slate
Pro', sans-serif;color:rgb(31, 73,
125);text-align:initial;background-color:rgb(255, 255,
255);">
<br>
</div>
<div style="font-size:initial;font-family:Calibri, 'Slate
Pro', sans-serif;color:rgb(31, 73,
125);text-align:initial;background-color:rgb(255, 255,
255);">
Regards </div>
<div style="font-size:initial;font-family:Calibri, 'Slate
Pro', sans-serif;color:rgb(31, 73,
125);text-align:initial;background-color:rgb(255, 255,
255);">
Crispin testing cooking stoves with short chimneys - will
report...</div>
<br>
<div style="background-color:#FFFFFF;">
<div class="ecxx_moz-cite-prefix">Dear Marc, Julien, and all
Stovers,<br>
<br>
There has been some good discussion (and hands-on work)
about the combustor on the TLUDs. Here are some
miscellaneous comments.
<br>
<br>
1. Marc wrote:<br>
<blockquote>(the paper says that the hole of the
concentrator ring should be 70% of combustion chamber
diameter. In terms of area, it means about 50%
combustion chamber area)</blockquote>
I think that is mis-stated. Most concentrators holes are
about half of the diameter of the full ring (fuel chamber
diameter). For 6 inch diameter fuel chambers, the size
most used for holes is 3 inch diameter (plus or minus half
inch is fine). That hole is only 25% of the area of the
whole disk. Dean Still (at Stove Camp) said that his is
with a 4" dia chamber has a 2" hole (if I remember
correctly).
<br>
<br>
2. Marc also wrote:<br>
<blockquote>I never liked (for cooking purposes) the
single-thick flame that comes out of the concentrator
ring that use most of the TLUD's designs, because you
get a narrow over-heated spot in the bottom of the
cooking pot, and in a result of that, you don't get a
good heat distribution in the pot.<br>
<br>
I made a new "diffuser" burner, which gives a circular
flame area, instead of a single one.<br>
<br>
<a moz-do-not-send="true"
href="http://youtu.be/mhl6tt2A4T0" target="_blank">http://youtu.be/mhl6tt2A4T0</a><br>
<br>
<div id="ecxx_inlineImage0"
style="display:inline-block;"><span></span><span></span></div>
<br>
Anyone knows any other works on this aspect?<br>
</blockquote>
<br>
The use of an annulus (ring) of gases for combustion (vs.
the central flame of concentrators) was in the very first
item ever written about what is now known as TLUD
stoves. See:<br>
<br>
<a moz-do-not-send="true"
class="ecxx_moz-txt-link-freetext"
href="http://www.drtlud.com/wp-content/uploads/2013/12/woodgas-stove-reed-larson-1996.pdf"
target="_blank">http://www.drtlud.com/wp-content/uploads/2013/12/woodgas-stove-reed-larson-1996.pdf</a><br>
<br>
And that stove has difficulties with maintaining flame
around the entire annulus when the supply of gases is not
high. What I think I have been reading by the recent
researchers is to have something like a concentrator and
then an annulus, ALL below the pot. I hope that can help
solve the issues.<br>
<br>
Paul<br>
<pre class="ecxx_moz-signature">Doc / Dr TLUD / Prof. Paul S. Anderson, PhD
Email: <a moz-do-not-send="true" class="ecxx_moz-txt-link-abbreviated" href="mailto:psanders@ilstu.edu">psanders@ilstu.edu</a>
Skype: paultlud Phone: +1-309-452-7072
Website: <a moz-do-not-send="true" class="ecxx_moz-txt-link-abbreviated" href="http://www.drtlud.com" target="_blank">www.drtlud.com</a></pre>
On 8/25/2014 2:04 AM, Marquitusus wrote:<br>
</div>
<blockquote>
<style><!--
.ExternalClass .ecxx_hmmessage {
padding:0px;
}
.ExternalClass body.ecxx_hmmessage {
font-size:12pt;
font-family:Calibri;
}
--></style>
<div dir="ltr">Hi Julien,
<div><br>
</div>
<div>Thank you for the info. and the paper.</div>
<div><br>
</div>
<div>Yesterday I was applying all this information to my
new burner design. I realized that, according to this
paper, the holes should be bigger if I wanted not to
reduce the draft. I assumed my new burner act as the
typical "concentrator ring", and make its empty area
to be the same size as the paper recommends (the paper
says that the hole of the concentrator ring should be
70% of combustion chamber diameter. In terms of area,
it means about 50% combustion chamber area)</div>
<div><br>
</div>
<div>What I can say since now, regarding the firsts test
with this new burner, is that apart from the
distribution effect, it mantains the mixing effect
(pyrogas+secondary air) of the classical concentrator
ring. I have observed that the flames coming out of
the secondary air entrance holes, tend to concentrate
in the center of the burner, just in the bottom of the
area wich is not open. Then they make a spin movement,
and finally find its way through the empy areas.</div>
<div><br>
</div>
<div>I suppose this movements in the bottom part of the
burner, very near the base of the flames, contribute
to the mixing process. But, as you say, I haven't
tried it under difficult conditions, so I cannot say
it would be desirable in all conditions.</div>
<div><br>
</div>
<div>Following your thoughts, I also think we should
have to find the optimal distance between the ring and
the secondary air intake. In this sense, <span
style="font-size:12pt;">I think that it should be
desirable to mantain this distance as short as
possible, in order to not losing heat through the
sides. If we put a long mixing/expanding tube
(chimney), we will have a very large emitting heat
area. If we find there is no alternative, then we'll
have to think about insulating all this area. That
is the reason why I try to mantain chimneys as short
as possible. What do you think about it?</span></div>
<div><span style="font-size:12pt;"><br>
</span></div>
<div>All the best,</div>
<div>Marc</div>
<div><br>
</div>
<div><br>
<br>
<div>
<hr id="ecxx_stopSpelling">
Date: Sun, 24 Aug 2014 09:56:59 -0400<br>
From: <a moz-do-not-send="true"
class="ecxx_moz-txt-link-abbreviated"
href="mailto:winter.julien@gmail.com">
winter.julien@gmail.com</a><br>
To: <a moz-do-not-send="true"
class="ecxx_moz-txt-link-abbreviated"
href="mailto:stoves@lists.bioenergylists.org">
stoves@lists.bioenergylists.org</a><br>
Subject: [Stoves] Trying new burner for TLUD's<br>
<br>
<div dir="ltr">
<div>Hi Marquitusus;</div>
<div><br>
</div>
<div>Your burner looks like an interesting idea.
It is worth checking to see if it will operate
under difficult conditions, such as low pyrogas
production from fuel > 12% (wet wt.)
moisture.
</div>
<div><br>
</div>
<div>I have been testing various options such as
annular rings for pyrogas, concentrator disks
(not rings cf. Anderson and Wendelbo), and
swirls. The problems with burners emerge with
the fuel I described above. What I find is that
(1) objects over the top of the TLUD reactor
that prevent secondary air descending toward the
fuel bed, and (2) swirls generated near the base
of the gas flame, don't work well under
difficult TLUD operating conditions. I am going
to post the results of experiments on these
shortly.</div>
<div><br>
</div>
<div>The conclusion I have reached (for the
burners I have tested) is that it is best not to
interfere too much with the bottom of the gas
flame.</div>
<div><br>
</div>
<div>However, once the gas fame is well
established, modifying it higher up in the
burner to create turbulence or spread the flame
could be a good idea. Therefore, I think your
idea has merit. If you haven't already done
so, you may want to experiment with the distance
your disk is above the secondary air intake,
i.e. is there sufficient space for the gas flame
to expand.</div>
<div><br>
</div>
<div><br>
</div>
<div>Based on the work by </div>
<div><br>
</div>
<div>Birzer, C; Medwell, P; Wilkey, J; West, T;
Higgins, M; MacFarlane, G; Read, M. 2013. An
analysis of combustion from a top-lit up-draft
(TLUD) cookstove. Journal of Humanitarian
Engineering, 2(1).
</div>
<div><a moz-do-not-send="true"
href="http://www.ewb.org.au/jhe/index.php/jhe/article/view/11"
target="_blank">http://www.ewb.org.au/jhe/index.php/jhe/article/view/11</a></div>
<div><br>
</div>
<div>you should check to see that the size of your
disk, relative to the burner outer
diameter, doesn't slow down the TLUD reaction
too much.</div>
<div><br>
</div>
<div><br>
</div>
<div>All the best,</div>
<div>Julien.<br clear="all">
<br>
-- <br>
</div>
<div dir="ltr">Julien Winter<br>
Cobourg, ON, CANADA<br>
</div>
</div>
<br>
_______________________________________________
Stoves mailing list to Send a Message to the list,
use the email address
<a moz-do-not-send="true"
class="ecxx_moz-txt-link-abbreviated"
href="mailto:stoves@lists.bioenergylists.org">
stoves@lists.bioenergylists.org</a> to UNSUBSCRIBE
or Change your List Settings use the web page
<a moz-do-not-send="true"
class="ecxx_moz-txt-link-freetext"
href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org"
target="_blank">
http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org</a>
for more Biomass Cooking Stoves, News and
Information see our web site:
<a moz-do-not-send="true"
class="ecxx_moz-txt-link-freetext"
href="http://stoves.bioenergylists.org/"
target="_blank">http://stoves.bioenergylists.org/</a></div>
</div>
</div>
<br>
<fieldset class="ecxx_mimeAttachmentHeader"></fieldset>
<br>
<pre>_______________________________________________
Stoves mailing list
to Send a Message to the list, use the email address
<a moz-do-not-send="true" class="ecxx_moz-txt-link-abbreviated" href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a>
to UNSUBSCRIBE or Change your List Settings use the web page
<a moz-do-not-send="true" class="ecxx_moz-txt-link-freetext" href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org" target="_blank">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org</a>
for more Biomass Cooking Stoves, News and Information see our web site:
<a moz-do-not-send="true" class="ecxx_moz-txt-link-freetext" href="http://stoves.bioenergylists.org/" target="_blank">http://stoves.bioenergylists.org/</a>
</pre>
</blockquote>
<br>
</div>
<br>
_______________________________________________
Stoves mailing list
to Send a Message to the list, use the email address
<a class="moz-txt-link-abbreviated" href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a>
to UNSUBSCRIBE or Change your List Settings use the web page
<a class="moz-txt-link-freetext" href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org</a>
for
more Biomass Cooking Stoves, News and Information see our web
site:
<a class="moz-txt-link-freetext" href="http://stoves.bioenergylists.org/">http://stoves.bioenergylists.org/</a><br>
_______________________________________________
Stoves mailing list
to Send a Message to the list, use the email address
<a class="moz-txt-link-abbreviated" href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a>
to UNSUBSCRIBE or Change your List Settings use the web page
<a class="moz-txt-link-freetext" href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org</a>
for
more Biomass Cooking Stoves, News and Information see our web
site:
<a class="moz-txt-link-freetext" href="http://stoves.bioenergylists.org/">http://stoves.bioenergylists.org/</a></div>
</div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
Stoves mailing list
to Send a Message to the list, use the email address
<a class="moz-txt-link-abbreviated" href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a>
to UNSUBSCRIBE or Change your List Settings use the web page
<a class="moz-txt-link-freetext" href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org</a>
for more Biomass Cooking Stoves, News and Information see our web site:
<a class="moz-txt-link-freetext" href="http://stoves.bioenergylists.org/">http://stoves.bioenergylists.org/</a>
</pre>
</blockquote>
<br>
</body>
</html>