[Gasification] Bisschop Engine – rough & ready

[AJH]

On Fri, 8 Sep 2006 00:08:34 -0400, Jeff Davis wrote:

>Andrew wrote:
>>I've allowed myself a little crosspost 
>
>Me to.

OK I've restricted this bit to [gasification]
>
>On Tue, 05 Sep 2006 18:48:22 -0600, Tom Reed wrote:
>>We are coming to the conclusion that producer gas has a very wide 
>>flamability limit.  This would be due to the ~20% H2 in it (like 
>>Synthane).  This would explain how a million non technical people could 
>>operate converted cars during WWII.
>
>~20% is great. Roy McAlister states ~10% min. when using hydrogen as a pilot 
>fuel.

I don't know who Roy is but I thought the amount of hydrogen was fixed
by the chemistry of the wood?

I see we have a similar difference in the use of "pilot" and "support"
as terms as we did with the difference between dual fuel and co
fueling. I'd have said pouring a bit of alcohol on some woodchips was
using a pilot fuel to light them, the requirement to keep another fuel
to sustain a continuing burn would be to use a support fuel to me.
>
>
>Andrew wrote:
>>Jeff Davis has mentioned running an "atmospheric" Bisschop engine on
>>producer gas,
>
>The Bisschop engine is not a “atmospheric” prime mover it is a 
>“non-compression”. At least that is my understanding.

Same difference I think, the thing runs without pre compressing the
charge, hence it runs from atmospheric pressure.
>
>Andrew wrote:
> >I've looked around and a chap I know, who builds model
>>engines, says that these early gas engines will not run on lpg or
>>natural gas because the mixture strength is so critical.
>
>Or is it the missing lubrication hence tar.

Pass on this but he would have used a proper lubricant.
>
>
>Andrew wrote:
> >He posted
>>that he had to resort to acetylene to get a similar engine to run. We
>>know acetylene has both high energy and a very wide flammability
>>range. 
>
>Acetylene is sooty and soot is a lubrication.

In this case I think not
>
>
>Andrew wrote:
>>This all points to producer gas being far more tolerant of
>>varying air:fuel mixtures than natural gas.
>
>Only if it has a good amount of H2?

As I said CO has a wide flammability range also, mind the flame speed
is much lower than hydrogen.

>
>It's my understanding that it is on the up stroke thus intake stroke.

I read that the intake and firing took place in the same stroke!

>popular. Do we really need more HP? One can do a lot with one-third HP.

Yes but at what cost, my guess is this thing has all the costs of a
normal reciprocating ic engine and the thermodynamic efficiency of a
steam engine.

>to macro-motion and we think that is great. It would be possible to heat your 
>home with a Bisschop engine and get some macro-motion for generating electric 
>or it could be used to power (macro-motion) an agglomerator to make fireballs 
>and the micro-motion (heat) would be used to dry them. Of course this would 
>all be on producer-gas.

And better done with a stirling engine??

>Hint: It would make a great engine to turn an agglomerator and the off heat 
>for drying the fireballs.

I like the concept, I once tried to persuade someone that our
"agricultural" gas turbine had exactly the right power to heat ration
to run a pellet mill and dry the sawdust from green, they opted to
build a small substation off the grid and an oil fired dryer.

AJH