<font color='black' size='2' face='arial'>
<div>Back when Teddy was at Odds with Arthur. Teddy imposed the three day week. I told my Boss that I could put ourselves back to a six day week with the aid of a Generator which we just "happened to have" for testing machines for export, This electric motor driven contraption was set up to produce 60 htz 3ph and needed to be "modified" to produce 50 htz. to run on NG. We needed about 20 HP for our requirements, So I got hold of a scrap Morris Minor Engine, and swapped it out with the electric motor,which was belt coupled to the Generator.<br>
Some changes in the taper lock pulleys and belts set the new contraption up for the lower frequency. Because the engine was "small" I decided to run it at a speed fitting it's optimum out put curve. There were other problems such as the field voltage control of the generator and the speed regulation to match the ever changing load of our small manufacturing plant. I envisaged the "Power Police" pouncing, armed with electrical measuring devices to make sure we were obeying the emergency directives. I designed a simple throttle control comprising of two identical synchronous motors, facing each other. where if they both ran at the same speed. the output leaver would remain stationary. one of the motors was powered by a battery powered "Shaving" inverter giving a steady 50 hrtz while the other clock motor was connected to one of the phases of the generator. It did work but due to the heavy fluctuating loads the out put was like a roller coaster.</div>
<div>I finally cheated, by putting three lamps between the grid supply and the generator and when they were all "out" I threw the main breaker and we were co-generating. A highly frowned upon practice due to the possibility of electrocuting unsuspecting grid lineman. In this case how ever. our small power plant could not have remained on line for more than a second if the grid had failed.</div>
<div>The grid stabilized our generator, I opened it up to full throttle and watched the Meter running backwards, which it did most of the time except when our large mill was in "start" mode. I am glad we did not have a visit from the power police.</div>
<div> </div>
<div>GF</div>
<div> </div>
<div> </div>
<div> </div>
<div> </div>
<div> </div>
<div> </div>
<div>-----Original Message-----<br>
From: Tony.Batchelor <Tony.Batchelor@tekura.school.nz><br>
To: 'Discussion of biomass pyrolysis and gasification' <gasification@lists.bioenergylists.org><br>
Sent: Sun, Feb 20, 2011 9:47 pm<br>
Subject: Re: [Gasification] ideal wood gas engine<br>
<br>
</div>
<div style="FONT-FAMILY: arial,helvetica; COLOR: black; FONT-SIZE: 10pt">
<div style="BACKGROUND-COLOR: #fff; MARGIN: 0px; FONT-FAMILY: Tahoma, Verdana, Arial, Sans-Serif; COLOR: #000; FONT-SIZE: 12px" id=AOLMsgPart_0_4d084dfc-a79a-414a-86fe-1028fcea5ed4><PRE style="FONT-SIZE: 9pt"><TT>Dear Kelvin and members.
This may be my first post to this site, I trust you will all not hope it is my
last.
Engine power output is a complex issue, factors such as the energy density of
the fuel, the air/fuel ratio that enters the engine, the volume of air/fuel
which is able to enter the engine during the induction stroke, and the
compression pressure reached prior to ignition and the mean pressure reached
during the combustion stroke are just some of the most important factors.
Besides the detailed design of intake manifold and exhaust pipes which influence
how well an engine can breathe.
Where an engine is to be run on wood gas alone, it would be better to do away
with as many obstructions in the intake manifolds as possible. The key point
being to get as much of the gas/air mixture into the engine. This is one reason
why Diesel engines are good as they only have suck in air, as fuel is added
internally. Fuel injected petrol engines come close behind, carburetor models
are generally more restricted as air passes through the carburetor.
Getting the Air/fuel ratio correct is also vital. Using a "colortune" sparkplug
is the best way to really know when you have the correct mixture as you can see
the flame color within the combustion chamber.
A turbocharger can be used to increase the volume of mixture which is drawn into
engine but whether or not they are practical given the possibility of
contaminated gas is something I cannot comment on.
The Mean effective pressure within the engine during the combustion stroke, is
largely dependent on the length of stroke of the engine, the compression ratio
and the ignition timing.
The stroke cannot easily be altered but the compression ratio can be changed on
some engines by machining the cylinder head.
Altering the intake air pressure, using a turbo or other methods. Such as
cooling the intake air/fuel temperature.
And by changing the ignition timing.
If a petrol (spark ignited) engine is run on wood gas or any other gas, the
Ignition timing has to be altered. In general the ignition timing will be
advanced by several degrees, in order to ensure as high a mean pressure as
possible is reached during the combustion stroke.
The benefit of using a computer controlled ignition system is that most if not
all computer controlled systems have a "knock" sensor. The purpose of this
device is to sense when the ignition of the fuel has caused the pressure within
the cylinder to rise so high that the remaining un burnt fuel spontaneously
explodes. This results in engine knock, the resulting noise is commonly known
as "pinking" Diesel engines knock a lot of the time because the very design of
the engine is to raise the fuel temperature to point when it spontaneously
burns.
Older engines that use a Distributor lack the anti-knock feature. Commonly
distributors have a simple mechanical advise mechanism, to advance the ignition
as the engine revs faster, and a Vacuum Retard mechanism which aids
acceleration. Engines which are subject to varying loads, can benefit from the
retard mechanism if there is any kind of control valve /butterfly on the intake,
which would alter the manifold vacuum.
Anyone setting the timing on an engine with a fixed load-speed, needs to be sure
the advance/retard mechanisms are either working correctly or have been locked
up. As fixed speed engines can "hunt" if there is any faults in or if there is
any small changes in the loading or fuel supply.
Tony Batchelor, ex, road transport engineer, now teaching physics. Wellington,
New Zealand.
-----Original Message-----
From: <A href="mailto:gasification-bounces@lists.bioenergylists.org">gasification-bounces@lists.bioenergylists.org</A> [<A href="mailto:gasification-bounces@lists.bioenergylists.org?">mailto:gasification-bounces@lists.bioenergylists.org</A>]
On Behalf Of Kevin
Sent: Monday, 21 February 2011 1:06 p.m.
To: Discussion of biomass pyrolysis and gasification
Subject: Re: [Gasification] ideal wood gas engine
Dear Charles
Your stated need is for "about 20 HP" at 1,800 RPM
You should be able to get about 21.4 HP with an engine of 2500 CC (153 Cubic
Inches), burning about 19 kG/Hr (42 Lbs/Hr)
It would be very helpful if others could comment on the other aspects of an
engine.... in particular, the Ignition system, whether Distributor or
"Computer Controlled", and the implications of using a Fuel Injected engine,
rather than a carburetor engine.
Best wishes,
Kevin
----- Original Message -----
From: <<A href="mailto:bayent@ns.sympatico.ca">bayent@ns.sympatico.ca</A>>
To: <<A href="mailto:gasification@lists.bioenergylists.org">gasification@lists.bioenergylists.org</A>>
Sent: Sunday, February 20, 2011 11:32 AM
Subject: [Gasification] ideal wood gas engine
>
> Content analysis details: (0.0 points)
>
> pts rule name description
> ---- ---------------------- --------------------------------------------------
> _SUMMARY_
>
> Hi All,
>
> I have several engines to chose from here for my next wood gas project.
> Going to go ahead with it and just hope the stink has settled form my
> insurance company ripping hair out of their heads. ( hope they are not on
> here.. bugger )
> Besides this is not a heating device so should not count.
> What out of the junk yard specials would be considered ideal for wood gas
> give I Only need this time to come up with 20 hp at 1,800 rpm?
> I have everything in the shop for a Mike clone.
> Spending a few bucks for the right engine is going to be real cheep just
> now.
> I am not keen on stuck valves through pistons. ( it that ever happens...
> never mind )
>
> Regards all,
> Charles
>
> _______________________________________________
> Gasification mailing list
>
> to Send a Message to the list, use the email address
> <A href="mailto:Gasification@bioenergylists.org">Gasification@bioenergylists.org</A>
>
> to UNSUBSCRIBE or Change your List Settings use the web page
> <A href="http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenergylists.org" target=_blank>http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenergylists.org</A>
>
> for more Gasifiers, News and Information see our web site:
> <A href="http://gasifiers.bioenergylists.org/" target=_blank>http://gasifiers.bioenergylists.org/</A>
>
>
> -----
> No virus found in this message.
> Checked by AVG - <A href="http://www.avg.com/" target=_blank>www.avg.com</A>
> Version: 10.0.1204 / Virus Database: 1435/3455 - Release Date: 02/20/11
>
_______________________________________________
Gasification mailing list
to Send a Message to the list, use the email address
<A href="mailto:Gasification@bioenergylists.org">Gasification@bioenergylists.org</A>
to UNSUBSCRIBE or Change your List Settings use the web page
<A href="http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenergylists.org" target=_blank>http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenergylists.org</A>
for more Gasifiers, News and Information see our web site:
<A href="http://gasifiers.bioenergylists.org/" target=_blank>http://gasifiers.bioenergylists.org/</A>
Warning: This email contains information which is CONFIDENTIAL and may also be
LEGALLY PRIVILEGED. If you are not the intended recipient you must not peruse,
use, disseminate, distribute or copy this email or attachments. If you have
received this in error, please notify us immediately by return email and delete
this email.
Thank you.
#####################################################################################
Scanned by MailMarshal - M86 Security's comprehensive email content security
solution.
Download a free evaluation of MailMarshal at <A href="http://www.m86security.com/" target=_blank>www.m86security.com</A>
#####################################################################################
_______________________________________________
Gasification mailing list
to Send a Message to the list, use the email address
<A href="mailto:Gasification@bioenergylists.org">Gasification@bioenergylists.org</A>
to UNSUBSCRIBE or Change your List Settings use the web page
<A href="http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenergylists.org" target=_blank>http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenergylists.org</A>
for more Gasifiers, News and Information see our web site:
<A href="http://gasifiers.bioenergylists.org/" target=_blank>http://gasifiers.bioenergylists.org/</A>
</TT></PRE></div>
<!-- end of AOLMsgPart_0_4d084dfc-a79a-414a-86fe-1028fcea5ed4 --></div>
</font>