<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body dir="auto" data-blackberry-caret-color="#00a8df" style="background-color: rgb(255, 255, 255); line-height: initial;">
<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);">
Howzit Lanny!</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>
</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);">
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>
<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>
</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);">
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>
<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>
</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);">
The reason this works is in part because air has quite a lot of oxygen and the air pressure is what it is. </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>
</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);">
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>
<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>
</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);">
At low power the EA will run to 2000 per cent easily in a side feed stove with an open architecture. </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>
</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);">
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>
<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>
</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);">
Regards </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);">
Crispin </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);">
BBM 2B567C3</div>
<table width="100%" style="background-color:white;border-spacing:0px;">
<tbody>
<tr>
<td colspan="2" style="font-size: initial; text-align: initial; background-color: rgb(255, 255, 255);">
<div id="_persistentHeader" style="border-style: solid none none; border-top-color: rgb(181, 196, 223); border-top-width: 1pt; padding: 3pt 0in 0in; font-family: Tahoma, 'BB Alpha Sans', 'Slate Pro'; font-size: 10pt;">
<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>
</div>
</td>
</tr>
</tbody>
</table>
<div style="border-style: solid none none; border-top-color: rgb(186, 188, 209); border-top-width: 1pt; font-size: initial; text-align: initial; background-color: rgb(255, 255, 255);">
</div>
<br>
<div dir="auto">
<div><br>
Interesting, is this self regulating?</div>
<div><br>
On May 15, 2014, at 9:39 PM, Crispin Pemberton-Pigott <<a href="mailto:crispinpigott@outlook.com">crispinpigott@outlook.com</a>> wrote:<br>
</div>
<blockquote type="cite">
<div class="x_WordSection1">
<div>
<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>
</div>
</div>
</div>
</blockquote>
<blockquote type="cite">
<div class="x_WordSection1">
<p class="x_MsoNormal"><span style="font-size:11.0pt; font-family:"Calibri","sans-serif"; color:#1F497D">Crispin</span></p>
</div>
</blockquote>
<style>
<!--
p.x_MsoNormal, li.x_MsoNormal, div.x_MsoNormal
{margin:0mm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif"}
span.x_MsoHyperlink
{color:#0563C1;
text-decoration:underline}
span.x_MsoHyperlinkFollowed
{color:#954F72;
text-decoration:underline}
span.x_EmailStyle17
{font-family:"Calibri","sans-serif";
color:#1F497D}
.x_MsoChpDefault
{font-size:10.0pt}
div.x_WordSection1
{}
-->
</style></div>
</body>
</html>