Redstone Diesel: woodgas optimized engine?

[jimmason]

to the long running pursuit of slow speed, big flywheel, run forever inexpensive engines, a new (old) one has recently been added. this is the redstone diesel.

after many years of not complete pleasure with the quality of listeroids and changfas, this is what joel koch and george utterbach, the gurus of slow speed diy engines, are now pursuing. you can read about the details here:

http://www.utterpower.com/Redstone.htm

http://www.woodnstuff.ca/redstone.html

i think we would all do ourselves well if we came up with a small engine that was optimized for woodgas. high compression, but still spark ignition, as dual fuelling is somewhat unsatisfying.

i have been looking to the changfa to do this. thus the gasifier genset skid we made from a changfa (well, really a flying fish). see here:
http://allpowerlabs.org/gasification...inadiesel.html

while this is a workable solution, and one that is important for the dev world as these changfas are everywhere, the changfa engine is a bit clanky.

the redstone looks like a better contender for the custom wood gas engine prize. it is direct injection, with good access to the cylinder, so installing a spark plug in place of the injector looks doable. there are nice mount points to take a timing signal off the flywheel to run a magneto or coil. at 15.5:1 compression, it is already about the opimal compression for a spark ignition syngas engine. might have to lower that slightly, but the elimination of the injector body and spark plug replacement might do this anyway.

someone should get one of these from joel and figure out the solution. there hasn't been a production engine optimzed for wood gas made since the 40s i believe.


jim

[jimmason]

one experiment i would like to try on a base like this is a is a pure compression fired, non-throttled wood gas engine. like a diesel, all air all the time. and like a diesel, add woodgas in as needed for power/speed. however, the fuel and air would be premixed at the intake the intake, like an otto, not the late fuel/air mixing of the diesel. given the extreme flammability limits of co and h2 (@5%-75%), i think you could run woodgas in this type of cycle. lean burn, full compression, full premixing, thus much cleaner running than the late mixing of a diesel.

this would give you the best aspects of the otto and diesel cycles, but combined into one engine. good efficiency and good emissions together.

the fire would be pure compression fire. not injection or spark based. but as such is never timed exactly where you want it, we could do it like a model airplane engine, as in with a glow plug, which is used to create the final temp to set off the compression fire.

if you run the engine with an unthrottled compression that is slightly below the auto detonation point, you could vary the heat on a glow plug to achieve the actual fire at the timing point you want. adjust the timing by adjusting the heat of the glow plug, not adjusting the spark timing.

thus instead of having to install a full spark system, just redo the injector as a glow plug, with variable power. probably could do this with the same push in and clamp down injector mount that holds the injector. actually, probably could start with a diesel engine, turn off the injectors, and run its glow plugs, variably powered.


this scenario will likely have a too lean point at low idle where it will not run. but i am pretty confident it would have a reasonable range in the actual power band.

this is one reason why woodgas is particularly fun. it has such different combustion characteristics than typical fuels, that you can start doing more exotic things with your heat cycle that are not possible with the other fuels.

see here for combustion characteristics of co and h2, as well as other common fuels. http://allpowerlabs.org/gasification...echart-800.jpg

jim

[Steve Unruh]

Yes Jim
The Austrian Jennbeckers are kidda' too big aren't they?
Slow piston speed with a long burn time is the way to go alright. I have an Indian paper here somewhere showing bio-gas useabiliy with both compression and spark ignition up to 17/1 compression ratio. I'll look for it.

I will be sticking with my Listeriod variable compression "sand machine" however, since I'm on the "SSS" banded list. And, I'm not the only one.
So, you will be on your own there. Good luck.

Steve Unruh, Yacolt WASHINGTON willcall distance to both Portland and Seattle. Hey, I like paying freight - keeps the truckers working.

[jimmason]

yes, i would like to see the paper to which you refer. by biogas do you mean methane?

but what is the "SSS" banded list?

[ToddT]

I have an email off to Joel already. I bought a Chinese gasifier from him about a year ago. Nice guy. Unfortunately, the Chinese gasifier was stolen before I had a chance to really dial in the operation.

An associate of mine works in the oil & gas industry here and knows a guy who modified the big Waukesha diesel engines to run on natural gas. These were used in gas compression stations.

Should a diesel on woodgas still suffer the 40% to 50% power reduction? What about a turbo/blower? What about an electric roots blower? The BioMax 25 uses a roots blower driven by a 3/4" hp electric motor for startup system vacuum. Why not use that for boost all the time?

[Steve Unruh]

OK I found it.
Jim these papers were highlighted by Ken Boak on the CSOG_Yahoo site.
This will take you to an archived India Institute of Science site:
http://eprints.iisc.ernet.in/cgi/sea...satisFyall=ALL
The paper to down load is titled "Biomass Gasification Technology - a route to meet energy needs
They specifically used a 3 cylinder DI engine to model different compression ratios and timing settings with duel fueled and spark ignition to test for optimum "producer gas" utilization. This was a 2004 study. Their highest widest graphed pressure rise was at 17 to 1 CR in dual diesel mode with injection timing at 34 degrees BTC.

I'll try the PM system on your other question.

ToddT if you look at the under-hood pictures Wayne has released he always uses a belt driven supercharger on his vehicles.

regards
SteveU.

[ToddT]

Steve, that link points to a page requiring login. When I tried to register, it said the system was only for an intranet. Is this something from work? Looked very interesting, though.

Where can I find Wayne's pics? I'm only familiar with the Yahoo WoodGas and the Gasification @ listserve.repp.com sites as other online communities dealing with gasification.

[Steve Unruh]

Wayne Keiths photo album can be found at:
http://www.ag.auburn.edu/agrn/bio-truck

I first entered the India site through Ken Boaks Yahoo CSOG group.
Perhaps they have a membership or license. Try that route. You will have to go back through the old woodgas posts there to retrace my breadcrumb trail.
It has loaded OK for me every time since then.

Regards
SteveU.

[ToddT]

My mistake, Steve. I rushed to sign up assuming I had to log in to view the documents. Sure enough... I clicked on your link and downloaded the document just fine. Now... to read all of this good stuff!!!

I couldn't tell much detail from the underhood pics. Is Wayne using a belt driven roots blower? Has he reported on before & after power differences?

Thanks again for posting it.

[jimmason]

re-rounding up the issue at hand . . .


i would very much like for us to come up with a woodgas optmized engine in the 7-25hp range. this is a critical part of the larger project i think. i just do not know yet what engine to use to do so. i want it to run around 1000-1500rpm. around 15:1 compression. and be spark ignition. dual fuel is less than fully satisfying at the small scale. very touchy.

the redstone is 1800cc and it produces right in the range wanted. maybe even a little too much. it seems impressive, but it is also a monster, and with the usual epa unknowns of working with simple chinese (or indian engines). the pipe could be turned off at any moment. even in good times, sourcing them is a big hassle.

so maybe we should be looking in the 1600cc range for more contemporary and regularly available engines.

here we have all the 1600cc compact car engines. we could run them slow and with a large added flywheel. acknowledge their superior engineering and ubiquity of availability. run them at stock compression, but put a junkyard turbo on them to get the compression up into better woodgas ranges. or mill the heads down to increase the compression. big plus: already have spark system. big minus: that spark system is computerized and good luck getting it working again.

the surplus center engines of contemporary design are not cheap.
http://surpluscenter.com/sort.asp?UI...s&keyword=NED1

the reefer unit diesel engines are the correct size and many are around. we could do those. but again, buying them new or refurbished, which one needs to do if this is going to be an ongoing concern, is not cheap. the solution needs to be more than a one off with obtainium.

the old vw diesel 1600cc engine would be a good platform too. there are lots of those around. the spark conversion would not likely be difficult.

or maybe we do it out of vw bug type I engines. there are still more of those around than near anything, and with every possible type of add on part. the lack of water cooling is non-optimal though if you want to do CHP.

the lister twin is the correct size, but also a monster, and with all the listeroid challenges. still, they have that nice plug right in the head which makes the spark plug insertion easy.

i like the changfa cause it is cheap, and when we figure out the solution the chinese can steal it and propagate it throughout the chinese hinterlands. they need some better power solutions over there or we're all in for it. so let's help em out.


thus i am confused. not sure really where to start. which of these engines, or others do people find a good candidates for a standardized and replicable wood gas optimized engine.

i do very much want to play with the just glow plug compression fire option. it seems likely this could be made to work, at less difficulty than a spark system.

jim

[claybj]

Fellow GEK'ers,

The pic here is of our soon to be power plant.

1. 6.2L GM Diesel we got from Joel
2. GEK
3. ST30 (never thought it would be this large)

We've got some basic mod's to do, which include a skid, safety features and some simple automation. Our initial goal is to test and re-test this particular engine on the producer gas. Lots of work to do. Once we are happy w/ engine performance, we'll hook up the ST30 and again work on engine performance.

There are a myriad of directions to take this type of power-plant. CHP being just one. Having this much potential torque gives us opportunity to push compressor, alternator, et al. We're not looking for a lite duty listeroid or redstone, which you can expect that we'll soon configure for smaller applications. We're after power and to prove just how long and how much service is required to run a larger engine 24/7/365 on producer gas.

We're 3 weeks from collecting any real data, but I will post to keep the boards updated on our progress, blood, sweat and tears.

- clay

[Terry J Reich]

What about Arrow engines? US made, Arrow engines run on a variety of low BTU gases; natural gas, methane, butane or propane.

also EPA Certified C-46, C-66, C-96 & Certifiable C-106

http://www.arrowengine.com/Products/...er/default.php

[claybj]

Just talked w/ Arrow as well as a Texas dealer for Arrow Engines... they want $12,500 for a rebuilt 32hp unit. That's way too much money.

[Steve Unruh]

Yes I lusted over a picture of a used 6 hp Arrow"K" engine for $6,000. about a year ago, then accepted my reality, and bought a 12 hp Listeriod single. Now with my engine, 7.5 KW genhead, pulleys, mounting, plumbing, ect. AND my GEK Stainless steel kit I still am comfortably under the price for that engine (missing radiator,starter and charging system) only.
Like JimM., I do not believe the Listeriod is a universal gasifier engine solution either. The Indian quality is too low, the engine to big, heavy and unportable for most.
Regards SteveU.

[Steve Unruh]

Can't get any sleep thinking about this quest. Problem is machinists friends tell me even with expensive popup pistons and machine work you still can't get 15/1 on most gasoline engines without the valves hitting the pistons.
So on a obtainium spark ignition gasoline based engine maybe Wayne Keith has shown us the way: supercharging
I found this man doing an eBay search: Dick Datson
http://gatorsuperchargers.net/
Regards-Enjoy
SteveU.

[jimmason]

Originally Posted by Steve Unruh

Can't get any sleep thinking about this quest. Problem is machinists friends tell me even with expensive popup pistons and machine work you still can't get 15/1 on most gasoline engines without the valves hitting the pistons.

this is true. i forgot about this. most mods to existing gas engines to up the compression are going to top out at around 9-10:1 before you are going to have valve/head interference. smaller volume heads are usually needed for larger changes.

as adding a spark system is easier than changing heads, this suggests starting from the diesel end is preferred.

or as you say, adding an intake pressurization system of some sort. the slower speed gator type supercharger will be much more forgiving of dirty gas than a turbo charger. particulates are a major issue with turbo blade speeds. the gator design runs much slower. but also robs shaft power.

either way, all of this is working against your efficiency wise unless you are already at over half power most likely. generating boost only to choke it off at the throttle plate is not helping things. the usual "gains" in efficiency from a turbo are allowing one to have a smaller displacement motor, with still adequate top power requirments.

and anyways, we have other good work to do with the heat. a turbo isn't the last gasp opportunity for the waste heat if you have an engine-gasifier system.

[GasMe Baby]

I can't imagine that Y'all haven't seen this.

http://www.capstoneturbine.com/prods...ucts/index.asp

And yes, I imagine it's much more expensive than a DIY diesel. Or an engine pulled from a wrecking yard. :)

If you just love your pistons, there's http://www.jasperengines.com/alterna...el-engines.htm too. You may get a "core" refund if you send them an old engine. I can't tell whether they mess with the compression, but they preset the engine computers to work right.

[Steve Unruh]

As a life long dedicated IC engine guy this thread will always draw me back.
Jim Mason you started this. Reading back as I review your posts this was the criteria you had lined out.
1)Optimized for woodgas
2) 7-25hp
3)1000-1500 rpm
4)15/1 compression
5)Spark ignition capable or convertable
6)Manageable size and weight and maximum usability
7)Ready availability, affordable price: $500? $900?
I have a list of 11 engines I currently own on my "bucket list" I wish to try woodgas fueling before I do finally kick the bucket. Goes from a tiny 125cc 3.1hp Honda up through a 5.0L I6 and V8 Ford. I won't bore you all with the whole list.
By your criteria Jim three in the middle come closest to matching:
My 1853cc/12hp Listeriod - but too big, heavy, expensive, and limited usability and availabilty;
My Yanmar 3T90J 1600cc 22hp 3cylinder watercooled diesel - but hard to find and too expensive to acquire, modify and service. Although would look great in a 1st gen Geo Metro 4dr. Hey, Wanna' Drag for 100MPGe AND claim a Issacs Ingallas's (sp) "Room for four people and their luggage" MINI practicality boast??
So finally down to my 20hp electric start V-twin air cooled overhead valve Kohler in my sawmill. Hm-m-m. Think about it.
I have an Aluminum capable TIG welder. I could popup dome the pistons or close down the combustion chambers as needed, or, use a Gator induction pressure booster.
This style V-twin engine is available from Honda, Onan, Kohler and Briggs and Stratton in 18-30hp. They all allready have an electronic spark ignition and most electric starting with a built in 10-20 amp 14 volt charger. Weights are between 85 to 150lbs. Current production, world wide availability's.
As far as air the air cooled complaints go: we know now we need to preheat and dry the incoming woody fuels - the air stream off of the engine is hot enough to do this without being too hot. And the wood isn't going to complain about hot oil smells. In the 27 years since I've been using Mobile1 0-40wt and then Castrol 0-50wt synthetic oils in my 4 stroke air cooleds I've yet to wear out even the cheap throw-a-way B&Ses and Tehcumsehs. With the industrial sized air cleaner and spark arrested exhaust system my Kohler twin is the quietest and smoothest air cooled I've been around including the VWs.
Take a look at:
www.generatorsales.com
Look around; then look in the Propane Natural Gas category at the 10kw "slow turning" belt driven 2200rpm Honda 24hp V-twin unit with the four pole MechAlte gen head as a concept. Then imagine it with couple of GeorgeB.s 3kw PMG heads one electrically clutched.

Wadda' you all think?

Regards
SteveU.

[oldchuck]

Steve, I think you are the ideal person to make reccommendations regarding stationary engines and gensets. I am pretty ignorant on the subject. There are so many choices.

You completely lost me with this one: "Then imagine it with couple of GeorgeB.s 3kw PMG heads one electrically clutched."

Looking forward to your continued reports. How do you like your sawmill?

[DanielChisholm]

Originally Posted by oldchuck

You completely lost me with this one: "Then imagine it with couple of GeorgeB.s

George B, of utterpower.com

3kw PMG heads

3 kilowatt permanent magnet generator heads http://utterpower.com/pmg.htm

one electrically clutched."

(I'm not following the significance of having one of them electrically clutched; perhaps to be able to have one always online, and to be able to add and remove the second one, to follow load requirements?)