[Gasification] SFC for De-rated EnginesWas:smallscalegasifiers for those that need them

[Peter Singfield]

At 12:40 PM 7/1/2007 -0700, you wrote:
>There are too many parameters that feed into engine life that it is 
>difficult to make a conclusive statement "doing this will reduce engine life 
>by 35%" by operating outside of one design point.  That is why I suggested 
>that Peter make a concerted effort to monitor blowby to determine what is 
>happening to his piston rings.
>

Well -- over the service period -- it still would work out the same -- as
the engine "strokes" 40 percent less!!

The big destroyer of these small single cylinder diesels is "VIBRATION" --
and that is greatly reduced when running at 60% of their "normal" rated RPM
---

Look -- some have been running two years now -- usually a Chinese single
running at rated RPM making power 8 to 12 hours lives from 10 to 14 months!!

Also remember -- the derated engine is much more "beefy" for the power it
is demanded to supply.

And that power is always about half of it's maximum rated -- anyway --
being as gensets need at least double capacity HP than regular steady load
to handle starting surges.

By the way -- running diesels at rated RPM but half of less load does not
hurt them??

That is running on to lean air/fuel mixtures 98% or more of their usage
time does not hurt them??

In the case example mentioned -- 98% of operation was at 800 watts and less
-- for a rated sweet point system of 3500 watts -- so less than 1/4!!

The deep well water pump added a huge surge factor -- but in the derated
system that is handled by the flywheel on the generator shaft (which you or
other also had to call a crazy idea -- promising it would destroy the
system!!)

Art - -excuse me -- your talking theory -- and large direct injection truck
engines -- scuse me -- I am talking 12 HP and less single cylinder diesels
-- and about "practice" -- not theory.

The rest of you one this list go the way you prefer -- it is no skin off my
butt if Art convinces the bunch of you what we are in affect achieving here
in real time -- simply can't be happening!!

Art -- the engines running derated are not banging away at full
charge/pressures either -- but only 2% or less of the time. The rest of the
time they run at around the half way point (rather than the 1/4 way point!!)

You have missed all the points so completely I am wondering what kind of
"religion" your belonging to these days??

My house runs average 800 Watts -- my system could put our 3500 watts --
running a single Lister at 750 RPM.

Now it runs at 375 RPM -- and maxes out -- black smoke -- at over 1500 watts.

But 98% of the time it runs only 800 watts or less!! 800 watts is maximum
(all lights -- all fans -- freezer - -computer -- everything)

The big deal is the system uses 1/2 the diesel -- that is 3 quarts of
diesel -- rather than 1.5 gallons -- to do this!!

And at 1/2 the rpm -- 1/2 the oil changes -- etc.

The mains are huge tapered ball bearings -- running splash lubrication --
they really do not care what RPM things are moving ta -- but slower is less
wear for them -- period!!

The rod big end is lubed by a small pipe attached to the bottom bearing cap
that splashes into the oil pool in the base -- there is no oil pump or
pressure lubrication system!!

Cooling is by "tank" -- it runs at boiling water temps -- no matter what RPM!!

Listen you all -- Art know best -- do as he says -- just ignore me and my
work -- that makes both Art and me happier -- win win situation as they say.

Art -- the Mennonites in Little Belize community have been running an old
Truck 250 Cummins diesel derated to 1100 RPM for five years now (naturally
aspirated) as a genset power plant -- and it still is running perfectly!!

What I would love to see is you coming here to tell them what fools they be!!

I would explain in detail why the gain of 50% in fuel economy -- but hey --
your "church" would not allow you to look at it anyway!!

Lean mixtures burn slower -- thus burn out through the exhaust stroke.

This also greatly increases engine heat -- as instead of energy going out
as "power" -- from the power stroke -- it goes out as combustion heat!!

Course -- according to Art -- hotter the better for a diesel -- and to cool
would destroy the engine!!

That you all take this "serious" -- is just to much!!

Oscar -- your into emulating "them" know??

Well -- there goes your ball park!!

True Oscar -- I have no grants or other monies to give out -- so I kind of
understand.

You hang with the Grants people -- and in my opinion -- they all will hang
together -- 

Your farmers where you are Oscar would have greatly appreciated the fuel
economy plus the much greater equipment durability -- but hey -- farmers do
not hand out grants either -- do they??

Art -- your really on some kind of a trip these days -- is all I have to
comment!!

You have impressed Oscar to no end with your brilliant deductions based on
theories-- the wrong parameters -- etc --

You must be responsible for grant approvals or something??

More blow-back because the combustion time is extended!!

How about more power thus economy because the time of expansion is increased??

Rather than run higher RPM -- much leaner fuel mixture - -thus much slower
combustion (gop check it out dude!!) thus most of the heat ending up in the
exhaust stroke -- increasing exhaust pressures -- greatly reducing engine
efficiencies -- and to much over heating!!

Your the only person I know of that suggests more waste heat in a diesel is
good for it!!!

And I have been lurking -- and watching all the list -- suck it all up!!

You folks are no longer into reasoned logical thought processes -- are you!!

And your sure great on denial of what is actually happening in observable
real time to -- eh!!

This is the last you hear from me on this subject -- these words -- right now:

Art is right -- it does not work -- motors blow up in mere hours -- so do
not even think of trying it -- keep burning twice as much diesel than you
need to make that power -- because after all -- change in your life styles
is non negotiable.

But we backward idiot fools here in 3rd world will continue running derated
diesels -- mainly because we "need" to make our power -- and we are so
stupid and don't know better!! We can't do the smart thing -- massive
deficit spending and li8ve off grant monies like you smart folks do!!

Art -- you especially -- should never be seen running a derated diesel set
up -- right!!

And some one better warn Ken Boak that he is destroying his Lister engine
running derated to!!


Peter/Belize