<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Agred there is anee to contrill excess air Lanny, <div>Aside form just lowering the pot you can also do what Rok Oblak did in his holly rocket stove design: <div><br></div><div>He added a simple metal plate baffle /choke/ in front of the inlet: <div>(thanks Rok, for the demonstration of your stove at our place in Ashland a few years back)<br><div><br></div><div>Richard Stanley</div><div><img height="640" width="427" apple-width="yes" apple-height="yes" id="bd5ad1d7-b4b3-4897-8940-ffb1d40b82ff" src="cid:DE5C72BC-7AFE-48A3-BE3B-A9D44323760F@hsd1.or.comcast.net."><img height="640" width="427" apple-width="yes" apple-height="yes" id="e0fe71a9-16cf-46b1-84df-d67eefba06de" src="cid:EF0D1807-832D-422C-86D7-2DCBD568BF0B@hsd1.or.comcast.net."><img height="640" width="427" apple-width="yes" apple-height="yes" id="20d34e9e-172a-4347-9e74-dde0d1f6de48" src="cid:8A9AFC51-0DC7-4BCC-B4E9-FAFD7F61767F@hsd1.or.comcast.net."><img height="427" width="640" apple-width="yes" apple-height="yes" id="71355595-8693-40fd-b5d5-9401b2b71ed8" src="cid:9B377017-2827-49E0-8407-D57C73168E69@hsd1.or.comcast.net."><img height="426" width="284" apple-width="yes" apple-height="yes" id="6c88a37b-b0e8-4283-ae1b-3437bfa5c33b" src="cid:B78089D2-7B1A-4003-BB18-E15F4EEFB68B@hsd1.or.comcast.net."><img height="284" width="426" apple-width="yes" apple-height="yes" id="63f5ae1b-2c06-4dc3-9cdd-86acc7208e0d" src="cid:7E427378-ABFD-48D0-8FA2-EFDA54C0C870@hsd1.or.comcast.net."><img height="640" width="427" apple-width="yes" apple-height="yes" id="69453e67-807a-4e81-8304-f10653a8fea4" src="cid:136DEAFD-5906-40C5-924A-B59963CB0755@hsd1.or.comcast.net."><br><div><br><div><div>On May 19, 2014, at 4:57 PM, Crispin Pemberton-Pigott wrote:</div><br class="Apple-interchange-newline"><div dir="auto" data-blackberry-caret-color="#00a8df" style="background-color: rgb(255, 255, 255); line-height: initial;">
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Howzit Lanny!</div>
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Yes, the idea is that if the internal chimney section of the stove (anything above the fuel bed in TLUD's) is hotter than the down-drafting section that is the secondary air preheater, it flows up and the secondary air flows down. The 'thickness' of the secondary
air channel matters - mustn't be too broad or cold air will pass in and out again. </div>
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The trick is to have the secondary air get less preheating when the power is turned down so it doesn't halt the secondary air feed. </div>
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The reason this works is in part because air has quite a lot of oxygen and the air pressure is what it is. </div>
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That means in the case of a side-fed stick burner, that there will always be too much air getting in if the draft is always upward - typically 6-800% excess air which is too much to burn cleanly. </div>
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At low power the EA will run to 2000 per cent easily in a side feed stove with an open architecture. </div>
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One simple way to limit it is to lower the pot and use it as a flow controller but it is only 'right' at one power setting. The down-drafting approach can be right across the power range. </div>
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Regards </div>
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Crispin </div>
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BBM 2B567C3</div>
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<div><b>From: </b>Lanny Henson</div>
<div><b>Sent: </b>Tuesday, May 20, 2014 08:48</div>
<div><b>To: </b>Discussion of biomass cooking stoves</div>
<div><b>Reply To: </b>Discussion of biomass cooking stoves</div>
<div><b>Subject: </b>Re: [Stoves] Natural draft TLUD turn-down</div>
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Interesting, is this self regulating?</div>
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On May 15, 2014, at 9:39 PM, Crispin Pemberton-Pigott <<a href="mailto:crispinpigott@outlook.com">crispinpigott@outlook.com</a>> wrote:<br>
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<div style="border:none; border-top:solid #E1E1E1 1.0pt; padding:3.0pt 0mm 0mm 0mm"><p class="x_MsoNormal"><span style="font-size:11.0pt; font-family:"Calibri","sans-serif"; color:#1F497D">I can suggest one additional effect to try which is to put a shell around the outside that is closed to the body at the bottom and open at the top. This
is a down-drafting secondary air preheater. The height of the upper lip strongly affects the performance so you need to find where to put it. The effect of this is to create a negative draft on the secondary air supply that balances the heat inside in such
a way that you get the exact airflow level you want at different power levels.</span></p>
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