Kevin,<br><br>You say: <br><i><font face="Arial"># OK!! A 50% reduction in boiling time is very
significant. <br>What can you now tell us that will enable us to apply it to other
stoves and combustion conditions?</font></i><br><br>I once did an experiment in which I made the 150 Belonio about half its original height.<br>I then filled it with chunks of wood and put a Belonio burner on top.<br>This was a natural draft unit without a fan.<br>
This is what it looked like:<br><a href="http://dl.dropbox.com/u/22013094/150%20Burner/Image2097.jpg">http://dl.dropbox.com/u/22013094/150%20Burner/Image2097.jpg</a><br>But looking back on this, I see that there were so many problems with this burner,<br>
even aside from the fact that it had no burner housing.<br><br>You raise an interesting question, though, which has always led me to wonder<br> why the Belonio burner hole pattern was not adopted on natural draft units.<br>
If a burner housing were added, I think the unit I experimented with would work much better.<br>The central problem that I see with a natural draft unit is an uneven upward flow of primary air.<br>At times too much CO2 is created, and some burner holes lose their flames.<br>
Also I would imagine that the inlet of primary air has to be strictly control to get a consistent outlet of gas at the burner.<br><br>A natural draft TLUD is very complicated,<br> and I truly marvel at those who get them to work on such a broad variety of fuels.<br>
<br>Thanks.<br>Paul<br><br>Thanks.<br>Paul<br><br><div class="gmail_quote">On Fri, Mar 16, 2012 at 12:36 AM, Kevin <span dir="ltr"><<a href="mailto:kchisholm@ca.inter.net">kchisholm@ca.inter.net</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><u></u>
<div bgcolor="#ffffff">
<div><font face="Arial">Dear Paul</font></div>
<blockquote style="BORDER-LEFT:#000000 2px solid;PADDING-LEFT:5px;PADDING-RIGHT:0px;MARGIN-LEFT:5px;MARGIN-RIGHT:0px" dir="ltr"><div class="im">
<div style="FONT:10pt arial">----- Original Message ----- </div>
<div style="FONT:10pt arial;BACKGROUND:#e4e4e4"><b>From:</b>
<a title="paul.olivier@esrla.com" href="mailto:paul.olivier@esrla.com" target="_blank">Paul
Olivier</a> </div>
</div><div class="im"><div style="FONT:10pt arial"><b>To:</b> <a title="stoves@lists.bioenergylists.org" href="mailto:stoves@lists.bioenergylists.org" target="_blank">Discussion of biomass cooking
stoves</a> </div>
</div><div class="im"><div style="FONT:10pt arial"><b>Sent:</b> Thursday, March 15, 2012 3:31
AM</div>
<div style="FONT:10pt arial"><b>Subject:</b> Re: [Stoves] radiant heat
capture, total heat measurement</div>
<div><br></div>
</div><div class="im"><div>As you all recall, Belonio and I, using the same reactor and the same
burner,<br> report a difference in boiling times.<br>I was bringing a
liter of water to a boil in about half the time that Belonio was
reporting.<br>I assumed this was because of the dome.<br>But this assumption
now appears to be completely wrong.</div><font face="Arial"></font>
<div><br>The dome does not reduce in any way the amount of time it takes to
bring a liter of water to a boil.<br>In an experiment this morning, I took the
dome off the burner<br> and put the pan of water at exactly the same
height as if the dome were in place.<br>I did a second experiment with the
dome in place.<br>The boiling times were exactly the same with or without the
dome.<br>I apologize to you all in leading you to think that thermal radiation
was making a big difference.</div>
<div> </div>
</div><div><font face="Arial"># No problem!! You raised some interesting questions
relating to stove operation and improvement.</font><div class="im"><br><br>So now the only
thing that remains to account for the difference<br> in boiling times
between Belonio and me is the burner housing that I put around the
burner.</div></div>
<div> </div>
<div><font face="Arial"># OK!! A 50% reduction in boiling time is very
significant. What can you now tell us that will enable us to apply it to other
stoves and combustion conditions?</font></div><font face="Arial"></font></blockquote>
<blockquote style="BORDER-LEFT:#000000 2px solid;PADDING-LEFT:5px;PADDING-RIGHT:0px;MARGIN-LEFT:5px;MARGIN-RIGHT:0px" dir="ltr">
<div><font face="Arial">Thanks!</font></div>
<div><font face="Arial"></font> </div>
<div><font face="Arial">Kevin</font></div><div><div class="h5">
<div><font face="Arial"></font> </div>
<div><br>The burner housing feeds secondary to the burner holes.<br>What you
see here:<br><a href="http://www.youtube.com/watch?v=nZDt8DfgSls" target="_blank">http://www.youtube.com/watch?v=nZDt8DfgSls</a><br> appears
to be just as efficient as what you see here:<br><a href="http://www.youtube.com/watch?v=yO3jcbQj-GI" target="_blank">http://www.youtube.com/watch?v=yO3jcbQj-GI</a><br><br>Here
is a picture of the burner with burner housing:<br><a href="http://dl.dropbox.com/u/22013094/150%20Gasifier/Boiling/IMG_1024a.JPG" target="_blank">http://dl.dropbox.com/u/22013094/150%20Gasifier/Boiling/IMG_1024a.JPG</a><br>
The
two parts are welded together.<br><br>Also I did another test in which I
boiled water without the dome -<br> but this time at about one inch lower
than the dome pan height.<br>This put the pan one inch closer to the
flames.<br>Again there was no difference at all in boiling times.<br><br>Also
I took several temperature readings:<br></div></div></div></blockquote>
<blockquote style="BORDER-LEFT:#000000 2px solid;PADDING-LEFT:5px;PADDING-RIGHT:0px;MARGIN-LEFT:5px;MARGIN-RIGHT:0px" dir="ltr"><div><div class="h5">
<ol>
<li>with the probe as close as possible to the blue flames: 646 C (probe
turned red)<br>
</li><li>with the dome in place and at the top of the dome: 463 C
</li><li>with the dome removed but with the probe at the same height as if the
dome were there: 532 C (probe turned red)<br>
</li><li>with the dome and with a pan of water above it: 390 C (probe situated in
between the two)</li></ol>
<p>Thanks.</p>
<p>Paul<br></p><br><br>
<div class="gmail_quote">On Thu, Mar 15, 2012 at 9:26 AM, Tom Miles <span dir="ltr"><<a href="mailto:tmiles@trmiles.com" target="_blank">tmiles@trmiles.com</a>></span> wrote:<br>
<blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote">Alex, Paul,<br><br>One option is to use a suction
pyrometer in which you pull the hot gas past<br>the thermocouple in a tube.
The tube limits the radiation so you get a<br>better picture of the true
temperature. Temperatures can be about 90C (200F)<br>higher in the suction
pyrometer than in a boiler or free air. A simple<br>version can be made with
compressed air venture drawing air through a pipe<br>with a thermocouple
inside it.<br><span><font color="#888888"><br>Tom<br></font></span>
<div><br>-----Original Message-----<br>From: <a href="mailto:stoves-bounces@lists.bioenergylists.org" target="_blank">stoves-bounces@lists.bioenergylists.org</a><br>[mailto:<a href="mailto:stoves-bounces@lists.bioenergylists.org" target="_blank">stoves-bounces@lists.bioenergylists.org</a>]
On Behalf Of Alex English<br>Sent: Wednesday, March 14, 2012 6:18 PM<br>To:
Discussion of biomass cooking stoves<br>Subject: Re: [Stoves] radiant heat
capture, total heat measurement<br><br></div>
<div>
<div>Paul,<br>So this makes sense. The screen radiates away heat
leaving a cooler gas<br>beyond.<br>If your thermocouple were smaller or
shielded the difference would likely be<br>even greater because the
thermocouple looses more heat from radiation when<br>it is
hotter.<br><br>Or are there other reasons, too?<br>Alex<br><br><br><br>On
14/03/2012 7:36 PM, Paul Olivier wrote:<br>> There are problems with what
I have written below.<br>> Let me again.<br>><br>> Without the
dome, the probe encounters hot gases and registers a<br>> temperature of
563 C.<br>> It turns red hot and starts emitting thermal
radiation.<br>><br>> With the dome, the probe encounter hot gases as
well as thermal radiation.<br>> But it only registers a temperature of
500 C.<br>> It does not turn red hot.<br>> Therefore the probe does
not absorb thermal radiation from the dome<br>> very
well.<br>><br>> Thanks.<br>>
Paul<br>><br><br><br>_______________________________________________<br>Stoves
mailing list<br><br>to Send a Message to the list, use the email
address<br><a href="mailto:stoves@lists.bioenergylists.org" target="_blank">stoves@lists.bioenergylists.org</a><br><br>to
UNSUBSCRIBE or Change your List Settings use the web page<br><a href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists%0A.org" target="_blank">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists<br>
.org</a><br><br>for
more Biomass Cooking Stoves, News and Information see our web
site:<br><a href="http://www.bioenergylists.org/" target="_blank">http://www.bioenergylists.org/</a><br><br><br><br>_______________________________________________<br>Stoves
mailing list<br><br>to Send a Message to the list, use the email
address<br><a href="mailto:stoves@lists.bioenergylists.org" target="_blank">stoves@lists.bioenergylists.org</a><br><br>to
UNSUBSCRIBE or Change your List Settings use the web page<br><a href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org" target="_blank">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org</a><br>
<br>for
more Biomass Cooking Stoves, News and Information see our web
site:<br><a href="http://www.bioenergylists.org/" target="_blank">http://www.bioenergylists.org/</a><br><br></div></div></blockquote></div><br><br clear="all"><br>-- <br>Paul A. Olivier PhD<br>27C Pham Hong Thai
Street<br>Dalat<br>Vietnam<br><br>Louisiana telephone: 1-337-447-4124 (rings
Vietnam)<br>Mobile: 090-694-1573 (in Vietnam)<br>Skype address:
Xpolivier<br><a href="http://www.esrla.com/" target="_blank">http://www.esrla.com/</a><br>
</div></div><p>
</p><hr><div class="im">
<p></p>_______________________________________________<br>Stoves mailing
list<br><br>to Send a Message to the list, use the email
address<br><a href="mailto:stoves@lists.bioenergylists.org" target="_blank">stoves@lists.bioenergylists.org</a><br><br>to UNSUBSCRIBE or Change
your List Settings use the web
page<br><a href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org" target="_blank">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org</a><br><br>for
more Biomass Cooking Stoves, News and Information see our web
site:<br><a href="http://www.bioenergylists.org/" target="_blank">http://www.bioenergylists.org/</a><br><br>
</div><p>
</p><hr>
<p></p><a></a>
<p color="#000000" align="left"></p><div class="im">No virus found in this
message.<br>Checked by AVG - <a href="http://www.avg.com" target="_blank">www.avg.com</a><br></div>Version: 2012.0.1913 / Virus
Database: 2114/4870 - Release Date: 03/14/12<p></p><p></p><p></p></blockquote></div>
<br>_______________________________________________<br>
Stoves mailing list<br>
<br>
to Send a Message to the list, use the email address<br>
<a href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a><br>
<br>
to UNSUBSCRIBE or Change your List Settings use the web page<br>
<a href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org" target="_blank">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org</a><br>
<br>
for more Biomass Cooking Stoves, News and Information see our web site:<br>
<a href="http://www.bioenergylists.org/" target="_blank">http://www.bioenergylists.org/</a><br>
<br>
<br></blockquote></div><br><br clear="all"><br>-- <br>Paul A. Olivier PhD<br>27C Pham Hong Thai Street<br>Dalat<br>Vietnam<br><br>Louisiana telephone: 1-337-447-4124 (rings Vietnam)<br>Mobile: 090-694-1573 (in Vietnam)<br>
Skype address: Xpolivier<br><a href="http://www.esrla.com/" target="_blank">http://www.esrla.com/</a><br>