A first stab would be to use an LM3224. It is way overkill as far as current capacity<br><br><div class="gmail_quote">On Thu, Aug 30, 2012 at 12:25 PM, Crispin Pemberton-Pigott <span dir="ltr"><<a href="mailto:crispinpigott@gmail.com" target="_blank">crispinpigott@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div link="blue" vlink="purple" lang="EN-CA"><div><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Dear Phil</span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">That was valuable info. The problem is not so much the volume of air needed, it is the pressure required to force some air through the fuel to maintain a pyrolysing bed.</span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">If you could stack fans running at a lower speed, it might give you the pressure. You sometimes see that on high end computer cases. The fans already have holes to allow this, it is so common.</span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">But it is probably better to use a lower voltage fan that is running at the right tip speed for its blade density. </span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">During an earlier discussion on fans a few years ago we pointed out that a squirrel cage fan is better for stoves because it so easily provides the pressure needed.</span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Do you have access to a DC-DC inverter chip to get the voltage up to 5?</span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Regards</span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Crispin</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal" style="margin-bottom:12.0pt">Amazing as it may seem, this off-grid Nicaraguan resident has some of those fans. So, I just gave one a test run.<br>
<br>It starts rotating at 3.22V but the speed is very slow at anything less than 4V. Even at 4V I would guess 25% or less of the air flow that you get at 5V. So, it is possible to use one but not directly from a single LiIon cell.</p>
<div><p class="MsoNormal">On Thu, Aug 30, 2012 at 9:42 AM, Phil Hughes <<a href="mailto:nicafyl@gmail.com" target="_blank">nicafyl@gmail.com</a>> wrote:</p><p class="MsoNormal" style="margin-bottom:12.0pt"><br><br>
</p>
</div></div></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" 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>
<br></blockquote></div><br><br clear="all"><br>-- <br>Phil Hughes <br><a href="mailto:nicafyl@gmail.com" target="_blank">nicafyl@gmail.com</a><br><br><br><br><br>