Hello all, I found this site a few months ago and have been hooked ever since, which was natural since I love all things with diesel, power generation, and self sufficiency. Anyways to the point of my first post here...I know that there is a lot of brilliant minds here so I would like to hear feedback, more specifically the challenges that I would face to do the following: (this idea has been in my head for the last couple of weeks)
Take a yanmar L100 or clone (186fe), make a custom liquid cooled cylinder to replace the air cooled jug, which will utilize a yanmar l48 or clone (170f) piston and head. This would create a 70x72 bore and stroke. Next, attach one or two large flywheels, think lister. You would end up with a small liquid cooled, direct injected, slow spinning, under-square engine.
Why I think this would be a good motor if it's possible:
1. Parts availability for these engines is second to none, and cheap
2. Liquid cooled for combined heat and power (I'm thinking a wet sleeve design would be awesome)
3. A slow turning mini engine with big flywheels like a lister would just be too cool, and we all know the benefits to slower operation having far less parts wear.
4. Direct Injection, currently a similar size motor is the r170f/r175f, and maybe those small kubotas I'm not too familiar with, but they are all IDI so less efficient, recently though I have been thinking IDI isn't all bad if you are harvesting the heat, it just means it is more of a heater than an electric generator ;)
Difficulties:
1. Air cooled design, cylinder head is air cooled how will that work with a liquid cooled cylinder? Can I make the air cooled head liquid cooled?
2. My original thoughts are aluminum outer cylinder with a cast iron wet sleeve, so making that all seal up with the aluminum block and head will take some engineering.
3. Will the connecting rod hit the longer cylinder?
4. Can the crank bearings support the large flywheels?
5. Balancing the new rotating assembly and flywheels, will the counterbalancing shaft complicate this?
6. Oiling, a common concern when we load engines at lower rpm's.
Anyways, let me know you thoughts on this so I can get a better idea of the feasibility of this harebrained idea.
Dont know about the restroking of the engine but water cooling is feasible. A mate of mine is into bucket racing (budget motorcycle racing with tight engine controls) and rather than go to a 250cc 4 stroke did a water cooledl conversion on a 125cc 2 stroke. He is failrly clever with small engines and figured that he could stop the huge power drop-off he was getting with his pretty "hot" 2 stroke when it was under long periods of high load by keeping the barrell and head at a more reasonable temperature. He jacketed the barrell and head individually and piped water barrell 1st then through the head and on to radiator. He used a 2nd hand pump off a motorcycle I think. I have seen this bike and the system worked and it went like stink. I think he drilled heaps of holes through the fins before argon welding the jackets on and used off-the-shelf motorcycle hoses and radiator. But it did work. The bike was never going to be asked to run for years driving a generator though.............?
First thing I'm thinking is how much power you going to get out of it?
186 does 8.5 hp @ 3600 RPM and thats a fair bit oversize to what you are proposing.
How much do you want to slow this thing down? As RPM is a function of power and I don't think it's linear, You might be looking at 2-2.5 HP @ 1200 Rpm. Someone might correct that but I'm pretty sure that the end is a lot of work for very little power output.
Think about a lister, 1.4L for 6HP. A medium size chainsaw will do that easily and you can hold that engine in one hand. The slow revs of the lister and the high revs of the chainsaw is what makes them compatible in output but different in every other way pretty much.
If you want slow revs with any decent power output, you are going to have to go up on the capacity to get any worthwhile useable power.
An awful lot of work for a very limited outpu both in heat and power.
I think you would be better off just leaving the engine as is and reducing revs a bit and taking the heat off the exhaust ( which still won't be much) or better still, just get a water cooled horizontal Diesel in the first place.
Those engines run nicely between 2500-3000 rpm's. They are designed to run between 2500-3600 rpm's. They do not run well at lower speeds loaded. The manufactures put lots of time in R&D. I feel your intentions are good but it will be very hard to do better than OEM's. They have the money to stress them out, blow them up, run them under less than ideal conditions, ect, ect. Most of us do not have that privilege. I would look for a used engine that is already designed for your specific application and rebuild it.
Now the Kubota ea300, eb300, el300, ea330 engines are good candidates to look at. I see these engines on craigslist often. They are good engines, parts are available, I would not be to concerned that they are IDI. They are still more fuel efficient than most IDI's of the same size. Another plus is they are very quiet. I posted some info on this forum someplace, the el300 is set up to run at lower speeds at 2000 rpm's. Output is 4 Hp.
Henry
Quote from: glort on November 24, 2013, 04:53:38 AM
First thing I'm thinking is how much power you going to get out of it?
Well I suppose at 1500 rpm it would be about (off the top of my head) 2hp or 1kw
QuoteI'm pretty sure that the end is a lot of work for very little power output.
Yes but if my goal is to have that lower amount of output, it would be better than having an oversized engine cycling on and off. I use about 1-2kw on avg and that is including electric heat, once I start using other heat sources...wood, heat from generator, it would probably be more like 500-1000 watts continuous. Also I enjoy doing this sorta stuff, so that whole lotta' work will make it that much more rewarding if it is successful. Also I would not just do it as a one engine deal, I would maybe make them in batches and sell kits to others who wish to the conversion, or even complete engines.
QuoteIf you want slow revs with any decent power output, you are going to have to go up on the capacity to get any worthwhile useable power.
displacement will be similar to the El300 and 165/170/175 changfas.
QuoteAn awful lot of work for a very limited outpu both in heat and power.
I think you would be better off just leaving the engine as is and reducing revs a bit and taking the heat off the exhaust ( which still won't be much) or better still, just get a water cooled horizontal Diesel in the first place.
I actually just picked up a r170f, pretty awsome little engine, but on this side of the pond, parts are not as easy to get compared to the yanclones, and it's aircooled.
Quote from: hwew on November 24, 2013, 07:50:28 AM
Those engines run nicely between 2500-3000 rpm's. They are designed to run between 2500-3600 rpm's. They do not run well at lower speeds loaded. The manufactures put lots of time in R&D. I feel your intentions are good but it will be very hard to do better than OEM's. They have the money to stress them out, blow them up, run them under less than ideal conditions, ect, ect. Most of us do not have that privilege. I would look for a used engine that is already designed for your specific application and rebuild it.
I plan on having a 170f (yanclone) and 186f in front of me and pullng them apart side by side, not a huge investment, < $1000, so I guess my main question is what specifically makes these engines only practical at 2500-3600 rpm?
QuoteNow the Kubota ea300, eb300, el300, ea330 engines are good candidates to look at. I see these engines on craigslist often. They are good engines, parts are available, I would not be to concerned that they are IDI. They are still more fuel efficient than most IDI's of the same size. Another plus is they are very quiet. I posted some info on this forum someplace, the el300 is set up to run at lower speeds at 2000 rpm's. Output is 4 Hp.
Henry
I don't know much about those little kubotas, but I'm sure they are high quality as all kubotas are, but I have never seen one locally on craigslist or ebay, are they common in marine applications? If so that would explain why none locally as I'm in Colorado. But also the fact that I'm not seeing any examples and almost no parts on ebay for them doesn't sit well with me. That would be the main advantage of making a slow speed liquid cooled yanmar, cheap parts and engines a plenty.
Thanks for the input so far, please keep it coming.
Quote from: focodiesel on November 24, 2013, 10:01:13 AM
Quote from: hwew on November 24, 2013, 07:50:28 AM
Those engines run nicely between 2500-3000 rpm's. They are designed to run between 2500-3600 rpm's. They do not run well at lower speeds loaded. The manufactures put lots of time in R&D. I feel your intentions are good but it will be very hard to do better than OEM's. They have the money to stress them out, blow them up, run them under less than ideal conditions, ect, ect. Most of us do not have that privilege. I would look for a used engine that is already designed for your specific application and rebuild it.
I plan on having a 170f (yanclone) and 186f in front of me and pullng them apart side by side, not a huge investment, < $1000, so I guess my main question is what specifically makes these engines only practical at 2500-3600 rpm?
QuoteNow the Kubota ea300, eb300, el300, ea330 engines are good candidates to look at. I see these engines on craigslist often. They are good engines, parts are available, I would not be to concerned that they are IDI. They are still more fuel efficient than most IDI's of the same size. Another plus is they are very quiet. I posted some info on this forum someplace, the el300 is set up to run at lower speeds at 2000 rpm's. Output is 4 Hp.
Henry
I don't know much about those little kubotas, but I'm sure they are high quality as all kubotas are, but I have never seen one locally on craigslist or ebay, are they common in marine applications? If so that would explain why none locally as I'm in Colorado. But also the fact that I'm not seeing any examples and almost no parts on ebay for them doesn't sit well with me. That would be the main advantage of making a slow speed liquid cooled yanmar, cheap parts and engines a plenty.
Thanks for the input so far, please keep it coming.
There are number of reasons why 2500-3000 would be best for these engines.
Critical Engine Speed
The size of the crank and rod bearings
Flywheel mass
Oiling system
And the list goes on.
I been around these engines long enough to understand where they run best. At low speeds these engines exhibit some pretty nasty harmonics and this is called critical engine speed. You want to run these engines out of that rpm range. We ran Yanmar L70 and L100 engines on water pumps and some L70 engines blew up. The cause was running at low speeds. These engines like running where I specified and they will live a long life.
The crank to rod angle is not the best on lots of these small diesels and in turn it puts stress on piston skirts at low speeds. The stress is reduced by running at higher speeds. It is all about R&D.
You say you don't know much about the kubota's. They are a very well built engine. Much stronger built than the Yanmar air cooled engines. Heavier crankshaft, larger bearings, cast iron head, re-sleeve able cylinder, larger flywheel. Parts are available at any Kubota engine and parts distributer. And prices are not out of line. I pretty much buy all parts at a local engine distributer and prices are cheaper than Ebay.
Shipping engines has never been a problem. Look at freightquote.com.
If you want to check out where these engines like to be ran call up Yanmar or Kubota and speak to one of the application engineers.
I understand the Yanmar clones are very cheap. But what you are thinking of, I cannot justify the time and cost.
There was a Kubota ea330 available not to long ago in Colorado. Just have to keep looking. It took me over a year to find the one I have.
Henry
Focodiesel,
In your first post you lister flywheels. My guess is your talking about CS flywheels. The crank will not be able to support all that weight by itself safely. And then there is safe rim speed. It is not recommended and unsafe to exceed the safe rim speed.
Henry
Some engines that are of interest to me are:
Volvo Penta MD1B
Bukh DV10
These engines can run slow.
QuoteI'm pretty sure that the end is a lot of work for very little power output.
QuoteYes but if my goal is to have that lower amount of output, it would be better than having an oversized engine cycling on and off. I use about 1-2kw on avg and that is including electric heat, once I start using other heat sources...wood, heat from generator, it would probably be more like 500-1000 watts continuous.
I'd suggest that -if- your power requirements are that low ( and I have read of very few people that are) then I would suggest you would be better off forgetting an engine and going with wind and or solar. No fuel requirement, less maintenance and virtually never wears out.
IF you are grid connected, I'd say an oversize engine is exactly what you want. Couple it up to a 3 phase induction motor and do a run back feeding to the grid. If your power consumption is so low you might only have to run the thing once a week to make back all your power. If you are off grid, a battery bank would be better than having to go start the engine every so often so the fridge and freezer can kick in or having the engine run 24/7. If you have a battery bank, again better to pump it up faster than slower.
QuoteAlso I enjoy doing this sorta stuff, so that whole lotta' work will make it that much more rewarding if it is successful. Also I would not just do it as a one engine deal, I would maybe make them in batches and sell kits to others who wish to the conversion, or even complete engines.
I think you will need to be doing it for the enjoyment because I can't possibly see you recouping your investment in time or money trying to sell people 2 Hp engines.
If you look here, the overwhelming theme is getting more power, not less. While your requirements might be very low, thats different to most people.
I would assess your market very carefully if you wish to make any sort of financial return.
QuoteIf you want slow revs with any decent power output, you are going to have to go up on the capacity to get any worthwhile useable power.
Quotedisplacement will be similar to the El300 and 165/170/175 changfas.
Exactly. Which is why you will have such low output. When was the last time you saw a 1KW alternator?
QuoteAn awful lot of work for a very limited output both in heat and power.
I think you would be better off just leaving the engine as is and reducing revs a bit and taking the heat off the exhaust ( which still won't be much) or better still, just get a water cooled horizontal Diesel in the first place.
QuoteI actually just picked up a r170f, pretty awsome little engine, but on this side of the pond, parts are not as easy to get compared to the yanclones, and it's aircooled.
I have an R165 and it's my favourite engine. that thing has more grunt than all my 5-6 HP rated engines and is just a fantastic little unit.
When I got it there were spare rings, bearings, gaskets and filters in the box. I can get these easily as well and I think it would take a long time to wear them out anyway.
IF this conversion is something you just want to try, fair enough. I don't think you are going to get much help with the tech questions because I think you'll be pioneering such a setup.
I think I'd be doing the water jacket, adding a flywheel and leaving it there. swapping the parts out sounds like there could be a lot of pitfalls. maybe just try the water jacket?flywheels first, run the thing some hours and see what happens before you invest too much in the project.
Hello focodiesel
Welcome to the MicroCoGen.
On your projected useage(s) for your converted engines you are approching this 85% from the wrong direction.
Self made power and heat begins with the fuel source.
Self made power and heat ends with just how much of this "fuel" you can afford to supply on a continuing basis.
Example there are two active members here in MarcusB. and RobertB. who thier fuel souce is wastes automotive fluids like engine/transmission and power steering fluids and oils. So thier resonable engine chioce IS the big slow CS 6 hp Lister clone India engines. Big, very low stressed, readily available cheap few parts allows them then to minimally pre-process their scrounged engine fuels. These are big, slow, and designed for sub-standard (by todays standards) heavy fuel oils. Even able to lubricate well with very simple engine oils.
The SLOW rpm speed always means longer life is utter bogus B.S. More important by far than the actual engine rpm is the actual piston speeds, lack of ALL internal abrasives, engine oil loadings and superior metallurgic matching.
Now for vegetable based engine fuels the big slow CS listeriods are kinnda sorta O.K. but the medium speed engine are better useable and many get better service with vegi oil fuels. Henry's recommened Kubota's 300 and 330 series; most of the water cooled ChangFa-iods and many others. This is glorts in use fuel and engines types.
Pump spec grade diesels then the more modern meduim to higher speed diesels will shine through with better fuel use efficiencies. Henry's and I think Derb's and mine and most others actual used fuels. Run these engines with good filtered and cooled spec grade lubricants and you will match and exceed the service hours of the older slower broader fuels tolorant tech engines.
And do this on the absolute least amout of spec grade pump petro fuel.
So man #1 what is your fuel type intent?
This along with later just how much engine fuel CAN YOU afford to purchase. beg, scrounge, grow and produce? on a continuous basis?? WILL drive your engine section.
Not just because container loads of cheap/available clone engines keep coming over from China . . . . . for now. Nothing last long. Do not lock your self in.
It is also NOT about how much power you desire. The above factors WILL force you to whittle down your power/heat consumer foot to fit your maintainable/affordable fuel/engine shoe.
Or even also NOT about how much engine waste heat you c-o-u-l-d use. The above factors in some climates some times of the year WILL you to have to supplement source fueling just for additional make up space heat. Same location, same climate some times of the years blowing off engine heats (wasting expensive fuel) from power generation just to get them out of the way from engine overheat damaging.
Always the Practical will rule over the Idealistic.
Regards
Steve Unruh - multi-times the acquirer of the wrong engine at the wrong time for the wrong use.
Quote from: hwew on November 24, 2013, 12:10:17 PM
Focodiesel,
In your first post you lister flywheels. My guess is your talking about CS flywheels. The crank will not be able to support all that weight by itself safely. And then there is safe rim speed. It is not recommended and unsafe to exceed the safe rim speed.
Henry
Yes similar to cs flywheels but obviously smaller versions. Thanks for bringing up rim speed, if I do create them I will definitely engineer them and be very
cautious. Also thanks for bringing up critical engine speed, I assume that has to do with harmonics and resonance frequencies?
You also discuss crank rod angle being steep on the yanmars...So a longer connecting rod would be better have less force on the skirt/cylinder wall?
Quote from: glort on November 24, 2013, 01:29:56 PM
I'd suggest that -if- your power requirements are that low ( and I have read of very few people that are) then I would suggest you would be better off forgetting an engine and going with wind and or solar. No fuel requirement, less maintenance and virtually never wears out.
I do plan on having solar. But why not have an generator too for backup and cloudy snowy days?
QuoteIF you are grid connected, I'd say an oversize engine is exactly what you want. Couple it up to a 3 phase induction motor and do a run back feeding to the grid. If your power consumption is so low you might only have to run the thing once a week to make back all your power. If you are off grid, a battery bank would be better than having to go start the engine every so often so the fridge and freezer can kick in or having the engine run 24/7. If you have a battery bank, again better to pump it up faster than slower.
I am grid connected, but the goal is to go off grid, I want nothing to do with back feeding my meter. The regulations are getting harder and harder, to me it is not worth it. Plus they will charge you all of the taxes, usage fees, demand side management... it is not long before a larger portion of the bill will be for things other than the electron work. I work for a power company so I can see all of this first hand. I understand the advantages, especially the near infinite load balancing, but at the end of the day it is an oligopoly and I wish to have off-grid peace of mind knowing I don't have to pay the ever inflating prices.
QuoteI think you will need to be doing it for the enjoyment because I can't possibly see you recouping your investment in time or money trying to sell people 2 Hp engines.
If you look here, the overwhelming theme is getting more power, not less. While your requirements might be very low, thats different to most people.
I would assess your market very carefully if you wish to make any sort of financial return.
Yes completely enjoyment, I am not thinking I will get rich quick off of this, more to hobbyists. I don't see why it is hard for you to see why I would spend so much time for a 2hp engine. Many members on board here spend countless hours on their 6hp cs listers, >20hp changfas, and other low power albiet reliable and efficient engines/alternators. Mobil bob has spent hundreds to thousands of hours tinkering with Leece Neville 110-555jho alternators that put out a max of what, 4kw in 48v form? I honestly don't think the overwhelming theme is getting more power, if that were the case people could buy a 200kw genset from military surplus for probably less than 20k. To me this stuff is about having fun, spending all of that time engineering and building and doing the poor mans r&d in the garage. A lot of what we do can't be justified financially if you start adding up labor costs. It's for the enjoyment factor.
QuoteIf you want slow revs with any decent power output, you are going to have to go up on the capacity to get any worthwhile useable power.
displacement will be similar to the El300 and 165/170/175 changfas.
QuoteExactly. Which is why you will have such low output. When was the last time you saw a 1KW alternator?
Thousands of them on cars and trucks.
QuoteI have an R165 and it's my favourite engine. that thing has more grunt than all my 5-6 HP rated engines and is just a fantastic little unit.
When I got it there were spare rings, bearings, gaskets and filters in the box. I can get these easily as well and I think it would take a long time to wear them out anyway.
yes mine came with rings, bearings, a filter, spare valves, honing compounds, and a whole slew of other cool stuff, and a great manual.
QuoteIF this conversion is something you just want to try, fair enough. I don't think you are going to get much help with the tech questions because I think you'll be pioneering such a setup.
I think I'd be doing the water jacket, adding a flywheel and leaving it there. swapping the parts out sounds like there could be a lot of pitfalls. maybe just try the water jacket?flywheels first, run the thing some hours and see what happens before you invest too much in the project.
I will appreciate any and all help I can get. Thanks for you're comments.
-focodiesel
Quote from: SteveU. on November 24, 2013, 04:18:15 PM
Hello focodiesel
Welcome to the MicroCoGen.
On your projected useage(s) for your converted engines you are approching this 85% from the wrong direction.
Self made power and heat begins with the fuel source.
Self made power and heat ends with just how much of this "fuel" you can afford to supply on a continuing basis.
Example there are two active members here in MarcusB. and RobertB. who thier fuel souce is wastes automotive fluids like engine/transmission and power steering fluids and oils. So thier resonable engine chioce IS the big slow CS 6 hp Lister clone India engines. Big, very low stressed, readily available cheap few parts allows them then to minimally pre-process their scrounged engine fuels. These are big, slow, and designed for sub-standard (by todays standards) heavy fuel oils. Even able to lubricate well with very simple engine oils.
yes a large portion of my fuel is wmo type fuels, I have had success with 50/50 in warm weather, and am working on fuel heating for cold weather and to try to run higher ratios, I currently have more wmo coming in than I can use. I would also like to experiment with adding woodgas to the intake, but that is far down the road.
QuoteThe SLOW rpm speed always means longer life is utter bogus B.S. More important by far than the actual engine rpm is the actual piston speeds, lack of ALL internal abrasives, engine oil loadings and superior metallurgic matching.
Utter bogus? the piston speeds are slower at lower rpm's, is this not one in the same? and wear increases with the square of the speed, I don't think that's bogus.
Hello foco,
Don't let everyones coments put you off, just pointing out the pitfalls , and there are many!!! As a suggestion read veggie's thread on a slow speed changfa , a very good read indeed if all you need is a modist output. All I'm after is about the same 1 - 1.5kw but constant and I'm curently trying a 165 same as glort.
If you continue on this path you have my vote, as long as you keep us updated with the good, bad and ugly.
Lastly you are right, if we took our time into account $$$$$ just goto work and pay the power bill.
Ian
Quote from: SteveU. on November 24, 2013, 04:18:15 PM
Hello focodiesel
Steve Unruh - multi-times the acquirer of the wrong engine at the wrong time for the wrong use.
Steve,
I always find your posts interesting but often very hard to digest or understand your overall point. Not the case here.
I think you made some excellent points and while many fly in the face of my own, I think what you say is very poignant and insightful. At the intended level of engineering the OP is looking at, no use building something that does not suit the intended fuel source.
Wise words from a man of experience and Knowledge!
Quote from: focodiesel on November 24, 2013, 06:40:32 PM
yes a large portion of my fuel is wmo type fuels, I have had success with 50/50 in warm weather, and am working on fuel heating for cold weather and to try to run higher ratios, I currently have more wmo coming in than I can use.
I have played minimally with WMO and can also get an endless supply but in the face of also being able to get all the veg I want ( and got someone offering me 3-4000L a WEEK if I want it a few days ago) I prefer that simply because it stinks so much less, spills clean up easier and clothes are somewhat more recoverable from spills.
What I did play a bit with is "Cracking" the WMO. There are a lot of people whom have developed this where they make their own diesel ( or petrol) fuel as they are really just refining what is already in the stuff.
To cut it short, I got a stainless beer keg, tapped in a 1/2" copper line that came out the top, went back under the keg in the flame of the WVO burner I built to act as the superheater portion then bubbled the vapours out in a container of water to condense them.
The resulting output of this crude as it gets system was to produce what I could best describe as a petrol/ diesel mix. It would light from a flame in a shallow dish but not burn for long before going out. The output worked really well in my 165 which is my main test engine.
You could Crack an amount of your oil and then blend it with the straight stuff to save you buying fuel to cut the straight oil. I think you would be able to use a lot more straight WMO than 50% on the testing I did. The other possibility is if you can get something like tranny and brake type fluids. These tend to be a lot thinner than wmo and may help reduce the amount of dino you need as well.
Have you tried blending with ULP? My little engine wont start on SVO in winter but with 10% ULP , no worries at all. I tested and found recently 5% ulp gave a power increase of using straight Bio which was a surprise. Needless to say the 5% also had better power than SVO. I don't know about the fuel energy and it's irrelevant to you but the ULP May save you in the amount of blending fuel you have to buy to get the engine to work with the WMO.
Simple cracking of the oil would no doubt save you even more.
For outright heating, You could build a small Burner that will run happily on any liquid combustible. You could scale down this design
to output anything from 1 KWh to 100 and beyond. There is also the " Uritz" type burner that is totally self sufficient and requires nothing but a fuel source and a good Chiminey draft.
Quote from: SteveU. on November 25, 2013, 09:41:41 AM
Good Morning focodiesel
Thank you for the waste motor oil fuel fill in that helps a lot.
Your Yamar clones IF you actually can get cylinder bore/pistons and rings and replacement injectors and pumps then makes sence. This is the superiority of the wet sleeved German origin Yanmar/Kubota/Changfa water cooled horizontal single cylinder derived engines.
Very good statement of wny a fellow would NOT want to go grid dependent. Sounds like from a man in-the-know. I speak as a fellow now locked into a radiometric digital tattle-tail meter. Even before these not a single person here was legally able to $$$$$$ challenge all of the hurdles that our grid supplier and there workers Unions would through up. And now with radio digetal meters they will hunt down all of the unregistered back feeders too as a 'war on drugs" Fed paid for program.
Well fellows wanting to still believe in grid connect "the Future" coming to you too. Mr focodiesel is absolutly correct about this.
YES on your reponse to Henrt's connecting rod length vs cranshaft stoke as related to piston side thrust pressure and friction/wear.
And these along with bore to stoke ratios determining actual piston linear travel distances per rpm are greater factors than just an overly easy mathmatical simplistic " wear rate squares with doubling of speed". THAT doesn not even account for the much better LOWER controlled wear rate that the more even heat distirbution your proposed to water cool convert will confer. ONLY the air-cooled manufactures like aircraft and Duetz industrial staying back to larger dispalcement lower thermal stresses building can come close to matching the longevity that water coolingby itself gives.
On the designed in geometical angles, thrusts and liniear wear fectors search up these actiual real world applications:
178 and 330 rpm big ships engines; many industrial large genrator sets IC piston engines manufacturers specs. Look at thier linear rated piston speeds. Compare thiers to calulated or quoted more common American V-8 eingine piston speeds. The SAME as in the longest lived V-8 engines. The hot-rodded racing engines and the factory hot engine all fall outside of this know best practices envelope. The engineeers know this - marketing/sales wanted what they wanted.
Other good examples of other wear fectors overriding abound all around you.
My visiting nurses wife's previous primary driving rig was a 1999 Plymouth mini-van 3.3L V-6 with now 250, 000 miles. Superior color change oil changes by me since day one. Still very quet and tight inside with no engine noises or visible cold exhaust oil smoke. Her bought new 2005 Hyundia 2.7L V-6 same oil change service. Same driving service doing exactly the load under the same conditions. Even very much the same cruising engine RPM's. Now at only 150,000 miles for the last 9 months blue oil exhaust smoke on cold starts and lash bled down hydraulic ticky-ticky valve lash ajusters for 2-5 minutes warming up time. And it now demands expensive 0-20 synthetic oil just to get those lash adjusters to fill and quiet down.
Why? #1 the American engine has a high flow actual postitve crankcase ventilation system. The Hyundia one of those PITA Asian "Tee'ed" overprseeure only flowing crancase ventilation systems the Do Not actually ventilate. So the averge oil running hours engine oil condition has been worse with consensates and combustions acids.
The older Amrican V-6 has a single in block roller lifter camshaft. The needing much oil componets are all down inside flooded and direct suppled with oil and the rotating fling off oil sprays are contaned and isolated from the needing little oil valve stems.
The Hyundia is an actual direct over the valve multi-camshaft system. To give the same flooding oil to keep the camshaft lobes alive then "the game" is to keep from spray fling off and drain back oil flooding the poor valve stems. L-o-n-g ways for the just sarted up engine oil to make it up to the oil needing componets. Well now the worn degraded valve stem seals can't hold back this oil from being negative pressure sucked into the intake and even the exhust manifolds.
But this newer more sophysticaed V-6 did help this manufactur to meet the later imposed thigher fuel use and emmisions standerd for new vehicles in it's years of manufacture. Plus give sales and marking more "sex" to sell versus "old fashion" cam in block tech.
My points ARE take into account ALL real world factors. Never just any ONE overiding factor. This rpm wear factor as just being the tip of the iceberg of tripping rabbit holes to get lost into.
Direct to the point: as Henry says stick with 2400-3000 rpm down speeding your Yanmar.Chinese clone.
Then you will not need "ship in a bottle" "Eeee! Ha! I turned my B&S into a 650 engine!" four stroke carry through flywheeling.
By all means DO water jacket it. This will help tremendously to dampen the noise. This will give you a small potential farmable off board pumpable heat source. Do read member Jens recent heat exchanger done-it advice on this.
For engine wear reduction focus on a remort larger capacity ool resrvoir and getting an oil filter some how involed if only just a bypass flow type.
Here on the MCG there will always be a bogus called on anyone single Eureka thinking they have found "the solution". One fellow once declared this as compression ratio jacking. Another fellow with regular unleaded gasoline other fuels blending.
This is not what I think you did with your down speeding proposal. We just want you to be very aware of all of the other factors involed also.
The Law of Uninteneded Cosequenses IS Real and bites $$$$ expensive hard.
Regards
Steve Unruh
Quote from: glort on November 25, 2013, 04:27:23 AM
I have played minimally with WMO and can also get an endless supply but in the face of also being able to get all the veg I want ( and got someone offering me 3-4000L a WEEK if I want it a few days ago) I prefer that simply because it stinks so much less, spills clean up easier and clothes are somewhat more recoverable from spills.
What I did play a bit with is "Cracking" the WMO. There are a lot of people whom have developed this where they make their own diesel ( or petrol) fuel as they are really just refining what is already in the stuff.
To cut it short, I got a stainless beer keg, tapped in a 1/2" copper line that came out the top, went back under the keg in the flame of the WVO burner I built to act as the superheater portion then bubbled the vapours out in a container of water to condense them.
The resulting output of this crude as it gets system was to produce what I could best describe as a petrol/ diesel mix. It would light from a flame in a shallow dish but not burn for long before going out. The output worked really well in my 165 which is my main test engine.
You could Crack an amount of your oil and then blend it with the straight stuff to save you buying fuel to cut the straight oil. I think you would be able to use a lot more straight WMO than 50% on the testing I did. The other possibility is if you can get something like tranny and brake type fluids. These tend to be a lot thinner than wmo and may help reduce the amount of dino you need as well.
Have you tried blending with ULP? My little engine wont start on SVO in winter but with 10% ULP , no worries at all. I tested and found recently 5% ulp gave a power increase of using straight Bio which was a surprise. Needless to say the 5% also had better power than SVO. I don't know about the fuel energy and it's irrelevant to you but the ULP May save you in the amount of blending fuel you have to buy to get the engine to work with the WMO.
Simple cracking of the oil would no doubt save you even more.
For outright heating, You could build a small Burner that will run happily on any liquid combustible. You could scale down this design to output anything from 1 KWh to 100 and beyond. There is also the " Uritz" type burner that is totally self sufficient and requires nothing but a fuel source and a good Chiminey draft.
Those are fantastic ideas I will definately try them thank you for the idea of it. Instead of cutting fuel costs in half one could eliminate them completely.
What do you mean by ULP? unleaded petrol? is that the same as RUG?
Quote from: uber39 on November 25, 2013, 03:28:29 AM
Hello foco,
Don't let everyones coments put you off, just pointing out the pitfalls , and there are many!!! As a suggestion read veggie's thread on a slow speed changfa , a very good read indeed if all you need is a modist output. All I'm after is about the same 1 - 1.5kw but constant and I'm curently trying a 165 same as glort.
If you continue on this path you have my vote, as long as you keep us updated with the good, bad and ugly.
Lastly you are right, if we took our time into account $$$$$ just goto work and pay the power bill.
Ian
Thanks for the encouragement, you know this may be a ridiculous and irrational idea, which is exactly why I want to test it against all of the experts who can give honest scrutiny to this idea to see if it is actually viable, so I am very happy with all of the responses, I am learning from them, but I can't learn from blanket statements like "it wasn't engineered for that use" because in order to overcome the obstacles I need to know what they are.
I will definately post very in depth write ups on this right here in this post, I am going to start by dismantling a 170 (l48) a 186 (l100) and my r170f side by side to see the differences in bearings, connecting rod lengths, and crankshaft sizes...
In my opinion you will have much greater success slowing down the 170 as compared to the L100.
The L100's are designed to run at 3000 rpm (up-rated to 3600 for the American 60hz. market).
I tried slowing down an L100 but the unit is very unstable below 1800.
Made for higher rpm's they have a light flywheel and a short stroke causing them to hammer at low speed.
The governor is quite unresponsive at low speeds of 1200-1500 also.
When I added small amounts of load, the engine bogged down without much reaction from the governor.
One key point with the 170 is the governor spring. Look for a spring which is about 1/2 the tension of the stock unit.
This will allow the engine to react at low rpms. If it does not react as needed, go even lighter.
I have a 175 which behaves quite nicely around 1100 rpm.
My 190 @ 1000 rpm would not react to load until I swapped the gov. spring for a very light one. Now it reacts instantly and holds 60hz. without hesitation.
https://www.youtube.com/watch?v=nZS-nrk7Eh4 (https://www.youtube.com/watch?v=nZS-nrk7Eh4)
good luck,
veggie
Quote from: focodiesel on November 25, 2013, 10:55:43 AM
Those are fantastic ideas I will definately try them thank you for the idea of it. Instead of cutting fuel costs in half one could eliminate them completely.
What do you mean by ULP? unleaded petrol? is that the same as RUG?
Yes, RUG is the term americans have to be different to the rest of the world like every other term they use. "Gas" to us is "propane" to you which is "LPG " to us.
Why can't you guys just speak English? ;D
Look up WMO Cracking or Distillation to see how the process is done. Basically it's just Boil the oil and recondense the vapours which leaves the heavy stuff behind. There is also a lot on turning plastic to oil and it's exactly the same process. One uses a liquid, one uses a Solid. I have also cracked veg oil which was interesting and worked well and something I may re Visit.
https://www.youtube.com/watch?v=KxgHX0wTYzE
Oh, and if you come across ANYTHING on Diesel from WMO or veg oil or whatever by a Jeffery S Brooks, Move on Immediately. The guy is a complete and utter nut Job that has been kicked off every forum he has been on ( and he's been through them all) for his psychopathic obsessions and pushing methods and practices that don't work. He espouses that his blends are successful Despite going through I think it was 5 injector pumps in 2 years and having to remove and clean his injectors every second tankfull on his mad Max look alike truck.
He's good for a laugh but quickly becomes scary when you realise just how off his nut he really is.
He's been here. I tried some of his recipes for making "translucent WMO" using RUG and acetone. It did settle some slop out of suspension, but it didn't solve the injector fouling issue.
No I just centrifuge filter, water separate and mix with an equal part #2. No failures over the last year or so except a few gelling instances when ambient temps drop below about 10 F. That's in my 6bt (ve pump).
Be careful and don't blow yourself up with that motoroil pot still!!
If your"worm" clogs you won't have much time to shut it down before it lets go with a bang.
Ron.
Quote from: vdubnut62 on November 25, 2013, 07:27:27 PM
Be careful and don't blow yourself up with that motoroil pot still!!
If your"worm" clogs you won't have much time to shut it down before it lets go with a bang.
Ron.
I was wary of that and so used 1/2" copper tube so there could be no pressurisation of the keg.
The water bubbling as well as doing a great job on condensing ALL the vapours ( unlike many that seem to let about 60% just blow away) is a good visual indication that the tube is not blocked.
I think the chances of that happening are very minimal because all the rubbish is left behind in the bottom of the keg and the superheater section is far too hot to allow the formation of carbon. It would be burnt off if it was there. After that the vapours are very light and the condensate is in a cool section which would not create any basis for blockages.
I would recommend either a blow off valve on the keg if one was available that would stand a suitably high temp or what I was going to do was try a blow off panel like used in racing circles on Supercharged cars. This would be a bit of aluminium can or other very thin and light sheet metal that was either just glued over a good size cutout section ( 2" or more ) with high temp silicone or Muffler putty or maybe with some self tappers in the corners and some sort of sealant.
The idea is to create a deliberate weak spot that will let go easily and well before anything else if a pressurisation does occour.
On my first cracking run, I had a bit of Hydraulic hose let go I was using on the end of the output tube before the Heat exchanger.
I have seen home made smoke bombs on youtube but the amount of smoke that instantly came out of the keg put them all to shame. I have never seen a thick billowing stream of smoke like it.
I immediately pulled the burner out and with the nearby hose, doused the bottom of the keg to cool everything down. The hardest part was getting near enough and beingable to see what I was doing. It worked quickly and effectively and I am confident that an over pressurisation could be brought under control of picked up when it happened.
Of course it would be critical to keep the water out of the oil but if cooling the keg, no problem.
The other thing I do now is have an old electric radiator fan blowing from one side so if anything ever does let go again, There will be a clear air side and the smoke will be pushed in one direction.
In that instance, I managed to stop the smoke plume before anyone called the fire Brigade which was a bit of a surprise given how it blanketed so much of the surrounding area in about 30 sec. Not to mention the smell wasn't exactly that of french perfume.
I would suggest if anyone is doing this to use something like I have which is a powerful burner rather than put it over a wood fire or any low heat gas ring etc. Your "Turkey Burners" may be OK, we don't have them here so I have no idea of their output but you want to pump a lot of heat into the oil because it takes a lot of energy to boil 40L of anything ( which is the batches I do) and you don't want to be taking up an entire day for something you will use in 10 Min flat.
One great way to bump efficiency I have used is to put the vessel you are heating inside another. I just use a 44 gallon drum with the ends removed. By enclosing the vessel being heated, you force air from the heat source up and onto the sides of the vessel which has a far greater surface area than the bottom which is all you heat when the vessel is not enclosed. Normally all that other heat is just dissipated so you increase the efficiency of the heat source many times over.
I did some tests with this a while back and although I forget the numbers now, The improvement with shrouding was huge and unmistakeable.
I guess i do have a reluctance to do this because of the dangers presented, the fact that you need to burn fuel to distill fuel, and then there will be an even thicker oil left over. I think before I go down this path I will try and perfect preheating my fuels prior to injection.
Quote from: glort on November 24, 2013, 01:29:56 PM
Quote
IF this conversion is something you just want to try, fair enough. I don't think you are going to get much help with the tech questions because I think you'll be pioneering such a setup.
I think I'd be doing the water jacket, adding a flywheel and leaving it there. swapping the parts out sounds like there could be a lot of pitfalls. maybe just try the water jacket?flywheels first, run the thing some hours and see what happens before you invest too much in the project.
I may start by doing just what you describe, water cooled cylinder and flywheel, this would keep the variables down, leaving the factory rotating assembly balancing alone, though I have been reading up on balancing engines.
I am now the owner of an l48 clone and a l100. I have started both of them up and they seem to be great little engines. One problem I have realized is the cylinder is integral to the block, which will take quite a bit of figuring to part off to create the new water cooled jug... Anyways this project is mid level on my list so it will be a while before I revisit this. Please keep the suggestions coming.
Check out my r170f
http://www.youtube.com/watch?v=CogV_AKb_kk
and yanclone 170
http://www.youtube.com/watch?v=AVRzIVl-mJs
Ahhh... Now I see. Your 170 is air cooled.
I thought your unit was a changfa type water cooled 170.
Those are fun little engines..
I have the 165... very similar to your 170
https://www.youtube.com/watch?v=KT4q1Z8vfew (https://www.youtube.com/watch?v=KT4q1Z8vfew)
This past summer I built a small gen set using the same yanmar clone as you.
https://www.youtube.com/watch?v=YKvT__sVzMI (https://www.youtube.com/watch?v=YKvT__sVzMI)
The yanmar clones are not well suited to slow speed running.
I run mine at 2500 rpm.
I did use it to drive a Leese alternator and for that test I ran the Yanmar clone at approx 1800 rpm.
Anything slower than that and the speed became unstable.
I was testing to see if I could power an inverter directly from an automotive alternate with using a car battery between, acting as a voltage clamp/buffer.
https://www.youtube.com/watch?v=UR57Hh611r0 (https://www.youtube.com/watch?v=UR57Hh611r0)
What will you be driving with your engine? This may help in determining the best engine for the job.
cheers
veggie
Dear Veggie,
Very nice looking generator! I like the paint...I think everything runs better with paint. Definitely something to aspire to! DF
Veggie,
From an efficiency standpoint, your generator looks like 1/3 of the fuel energy goes out the exhaust, 1/3 becomes waste engine heat, 1/3 produces mechanical energy to turn the generator, and 1/3 becomes sound ;D ;D ;D
Wow.... Thats 4/3rds! awesome!
Veggie,
That L186 seems to like 2500 RPM better than 1800. At 2500 it is not stressed at all and should have a long life.
Henry
Very nice genset, Veggie. Very interesting to hear the Yanmar clone at 2500 and 1800 rpm. It does sound smoother at 2500.
Quote from: bschwartz on December 16, 2013, 12:35:12 PM
Veggie,
From an efficiency standpoint, your generator looks like 1/3 of the fuel energy goes out the exhaust, 1/3 becomes waste engine heat, 1/3 produces mechanical energy to turn the generator, and 1/3 becomes sound ;D ;D ;D
Yes Brett, that was my first attempt at over-unity perpetual energy.
When I achieved 4/3rds power production, I got scared and abandoned the project fearing a "run-away" which might engulf the planet in excess energy. ;D
veggie
focodiesel,
If you are still considering a water cooling conversion to one of your engines, consider this...
I once pondered converting my air cooled Honda GX gasoline engine to water cooling in order to capture heat.
The idea was to remove every second row of cooling fins and wrap the cylinder (in between the fins) with soft copper pipe.
Perhaps a heat transfer putty could be applied between the cylinder and the coil to aid with contact area.
Fins would not have to be removed if a small enough diameter copper tube is used.
A small section from each fin would be removed to allow to copper coil to drop to the next set of fins.
By looking at the shape of your cylinders, this modification may be better suited to your 170 than the Yan-Clone.
Obviously this would not be as efficient as a true water jacket but it might be useful in capturing heat.
The harder part is the cylinder head. How to capture heat from the head ?
Because this was not a priority, I did not proceed with the project, however I leave it with you to decide if it's worth pursuing.
keep us posted,
veggie
I can't remember where, but someone on these forums suggesting using a radiator to capture heat from an air cooled engine. Hot air from the engine is director thru the radiator, heating the water inside which flows to the heat tank/storage/etc. I have no idea how well that would work, but it sounds much easier than attempting to get the right water flow around an air cooled engine.
Quote from: veggie on December 15, 2013, 07:40:16 PM
What will you be driving with your engine? This may help in determining the best engine for the job.
Very cool setups veggie thanks for sharing, I was already one of your subscribers on Youtube!
As for the alt, I was thinking a 555-110jho, 24v mobile bob style.
Quote from: Thob on December 17, 2013, 10:23:50 AM
I can't remember where, but someone on these forums suggesting using a radiator to capture heat from an air cooled engine. Hot air from the engine is director thru the radiator, heating the water inside which flows to the heat tank/storage/etc. I have no idea how well that would work, but it sounds much easier than attempting to get the right water flow around an air cooled engine.
I would think that the heat transfer using that method would be far less than that of a water jacket, but I may just duct the heated air into the space to get chp out of an air cooled. But ultimately I want a liquid cooled engine because hydronic heat is much easier to utilize (pipe vs duct).
The old VW beetle used the shrouded hot air for the heat and defrost. Alas, not very useful in sub zero temperatures, especially after running through uninsulated steel ducts in the airstream along the running boards. But it certainly proves the concept.
You know.....before I'd go through the trouble of etc., etc. I would do an experiment with the engine exhaust...the various combustion classes I have been in, all are fond of saying that 90% of the heat goes out the exhaust....perhaps the 10% coming off the fins isn't worth the effort.
Another thought is that, regardless of what percentage is lost through the fins...you must ask yourself what heat is actually available. For example, my L40 offers 2.8kw continuous so pretend its 20% efficient and divide 2800 by .2 and you can see I'd have 14000 watts available for heat. Now for my situation, that probably is enough. If you are wondering about yours, either learn to read your natural gas meter, or fire your furnace on a 20lb cylinder sitting on a bathroom scale to find out how much fuel you are burning in an hour. Basically, heating your house is all about how much heat your house rejects (or loses) per hour. The question is whether the engine will actually be burning enough fuel to come close to the amount of heat your home is rejecting.
I have been saving exhaust heat exchangers for years, for the purpose of one day installing them on the L40s. I have yet to bring myself to go through the trouble because I actually live off grid, and do not enjoy the continuous rattle of a generator. Where as, a wood stove or an oil space heater is silent.
anyhow, this time of year is perfect for armchair speculation, and lots of interesting ideas come out of it...
BPJ
Always cold here now. Been artic COLD now too much already this heating season.
I'll echo Duelfuels observation about monitoring your whole house for heat loss usage. I'm not actually off-grid and am forced by State regulations to have to maintain primary house heating sources other than wood by law. And this gets inspected, monitored and enforced by the State chartered and licenced home owners insurance companies.
This makes it easy to come up with hard numbers for gross heat needs by just running and monitoring the forced air electric furnaces for 24 hour periods in different inside/outside temetature/humudiry changes and between whole house upgrades like windows and insulations.
My hard numbers are that I need an minimum of 10,000 BTU's per hour for every 10 F temperature differential outside to inside that I want to maintain.
HAVE spent the money to be able to say screw you State/EcoFreekin/Greens!!! and upgrade (to State emmisions standards) and still maintain whole-house, in-house bulk wood stoves.
Just woken this morning 2 hours before sun up by the elecrric furnace cycling from the house six hour cooling down.
30 minutes of silent kicked back up woodstoving put a stop to that $$$'s for BTU's.
Side benfits of woodstoveing for space heat over and above using the trees I'm already Ceasar tax invested in; and the keep you up, moving, and young working is the whole house ventilation and dehumitfing SILENTLY that the woodstove provides. Gets real stuffy wet inside after 2-3 days of just the furnce with no AC/refigerent cycle to dehumidify with.
I live in an aways condensing rain forest. Interior humidy control for green, black and unseen molds molds is critical.
No matter which engine wear belief you suscribe to; can be no argument that a sitting non-running IC engine wears much less and is a heck of a lot cheaper to maintain than any running IC engine.
And it is much more pleasant to sit in the silent bone warming glow of a bank of wood coals than any other form of irritating, expensive to maintain blowing space heating.
Regards
Steve Unruh
Quote from: Dualfuel on December 18, 2013, 04:44:18 AM
You know.....before I'd go through the trouble of etc., etc. I would do an experiment with the engine exhaust...the various combustion classes I have been in, all are fond of saying that 90% of the heat goes out the exhaust....perhaps the 10% coming off the fins isn't worth the effort.
Another thought is that, regardless of what percentage is lost through the fins...you must ask yourself what heat is actually available. For example, my L40 offers 2.8kw continuous so pretend its 20% efficient and divide 2800 by .2 and you can see I'd have 14000 watts available for heat. Now for my situation, that probably is enough. If you are wondering about yours, either learn to read your natural gas meter, or fire your furnace on a 20lb cylinder sitting on a bathroom scale to find out how much fuel you are burning in an hour. Basically, heating your house is all about how much heat your house rejects (or loses) per hour. The question is whether the engine will actually be burning enough fuel to come close to the amount of heat your home is rejecting.
I have been saving exhaust heat exchangers for years, for the purpose of one day installing them on the L40s. I have yet to bring myself to go through the trouble because I actually live off grid, and do not enjoy the continuous rattle of a generator. Where as, a wood stove or an oil space heater is silent.
anyhow, this time of year is perfect for armchair speculation, and lots of interesting ideas come out of it...
BPJ
I think diesels are closer to 40% thermal efficiency so in that case let's say 7kw heat for your example. I actually currently use electric heat so it's easy to figure out what it takes on the coldest days (a week ago in CO) about 4kw will keep it warm. Also are you sure about the 90% exhaust heat statement? I have always heard about 1/3 exhaust heat, 1/3 conduction heat, 1/3 kinetic power.
Ahhh, let me clarify. Lets pick your 40% thermal efficiency....meaning 4/10ths of each gallon is converted from heat to work....the other 6/10s is wasted heat....of that wasted heat, 90% goes out the exhaust.
But don't get hung up on the numbers....what is important is the idea....you have to ask yourself...at what percentage is it actually worth going after the fin heat? You intuitively know that most of the available waste heat is already in the exhaust gas...thats the low hanging fruit. The test you should perform is whether to find out if the exhaust heat is enough to heat your house. If so, then you don't have to pursue the liquid cooling idea and go directly to the heat exchanger calculations. For example, what quantity of liquid will the system hold, inorder to transfer the heat from the exhaust to the in-house heat exchangers? That can be a from the hip" guess or you can find out how much heat your in-house exchangers reject and work backwards with pump flow rate.
I know if it was my project, the constraint would be in which type of junk I had laying around to plumb up.
The slick thing is to go whole hog hydronic, then install an electric heating element as a back up. Put the electric meter where you cannot avoid seeing it...then let the dismay of watching it spin, propel you off the couch and out into the gen shed to pull the rope.
as an aside the whole efficiency thing is terribly difficult to nail down unless, you go for the total fuel in versus electricity out measurement. But for heating purposes that number is not helpful. Thermal efficiency is purely theoretical, AND saying 40% is converted to work, is not actually describing what work is being done...for example, blow-by is work, keeping the metal expanded due to heat is work, pumping lube oil is work, friction is work. None of these are of any value to your heating measurements. The number that is valuable to you is the brake specific fuel consumption. Knowing how many pounds of fuel your engine uses per hour can be found using the BSFC chart for your engine.
Ball park numbers for what you need can be found at the Beckett Oil burner site...typically .4 to 3 gallons per hour. Good BSFC for a yanmar is .4 lbs/hp*hour so 2 lbs/hour for 5hp.....so you might be coming in low at 5hp, seeing as 2lbs is .3 gallons.
There in lies the rub....my engine will not actually burn enough fuel to make it worth setting up a heat exchanger for a house. Perhaps heating a battery room would be more practical, or heating the wood shed...but unless I start burning enough fuel to operate an engine somewhere above the 5hp output range, it simply would be an auxiliary, which means I'd be burning wood anyhow.
Its a very interesting problem in itself, with most of the data available through the internet and ASHRAE. I think the problem becomes moot when you do a cost benefit analysis on the money spent versus heat input.
DF
Quote from: Dualfuel on December 18, 2013, 06:29:31 PM
Ahhh, let me clarify. Lets pick your 40% thermal efficiency....meaning 4/10ths of each gallon is converted from heat to work....the other 6/10s is wasted heat....of that wasted heat, 90% goes out the exhaust.
Yes I understand what you are saying, but I think you may be incorrect about your 90% statement, I have typically heard 2/3rds of combustion energy content is converted to heat, half conducts through the cylinder to the coolant and/or air , half goes out the exhaust, or as common rule of 1/3,1/3,1/3. I think it is important to clarify this.
Quote
But don't get hung up on the numbers....what is important is the idea....you have to ask yourself...at what percentage is it actually worth going after the fin heat? You intuitively know that most of the available waste heat is already in the exhaust gas...
No, that's where the confusion was, I did not intuitively think most of the heat was in exhaust gas, It is very reasonable to think there is a sizable amount of heat lost to conduction when you observe the size of radiators on liquid cooled engines.
So if there is equal heat lost to exhaust and conduction, It then comes down to what is easier to harness, In my eyes it is a liquid cooling system, once that has been built, than try and go after some of that heat in the exhaust.
QuoteThermal efficiency is purely theoretical, AND saying 40% is converted to work, is not actually describing what work is being done...for example, blow-by is work, keeping the metal expanded due to heat is work, pumping lube oil is work, friction is work. None of these are of any value to your heating measurements.
No, no...thermal efficiency can be very specifically described, calculated, and measured. it is not arbitrary or subjective. The "work" is power produced off of the crankshaft. I don't quite know what you mean by blow-by and keeping the metal expanded due to heat as being work, but as for pumping lube, yes it takes power but ultimately parasitic loads turn into heat, sound, or some other form of energy, and yes these "lost" loads are factored in to thermal efficiency mainly turning up as heat. Friction, again mainly turns into heat which is conducted away into the coolant/air.
QuoteThe number that is valuable to you is the brake specific fuel consumption. Knowing how many pounds of fuel your engine uses per hour can be found using the BSFC chart for your engine.
Ball park numbers for what you need can be found at the Beckett Oil burner site...typically .4 to 3 gallons per hour. Good BSFC for a yanmar is .4 lbs/hp*hour so 2 lbs/hour for 5hp.....so you might be coming in low at 5hp, seeing as 2lbs is .3 gallons.
Good to know, thanks I will look into that.
QuoteThere in lies the rub....my engine will not actually burn enough fuel to make it worth setting up a heat exchanger for a house. Perhaps heating a battery room would be more practical, or heating the wood shed...but unless I start burning enough fuel to operate an engine somewhere above the 5hp output range, it simply would be an auxiliary, which means I'd be burning wood anyhow.
Its a very interesting problem in itself, with most of the data available through the internet and ASHRAE. I think the problem becomes moot when you do a cost benefit analysis on the money spent versus heat input.
DF
You may be right, your engine may not be ideal for heating your place, for me, 4 kw of heat is very attainable through waste heat capture. Another strategy I will employ is to have an electric water heater in series of my hydronic system, if there isn't enough heat output from the prime mover, and spare power capacity, you add the load of the heating element, further heating the water directly and loading up the engine which will in turn create more engine heat...
As for the cost benefit analysis, that has been covered earlier in this post. If we didn't factor in the enjoyment of creating, tinkering, and engineering this stuff and actually calculated the "labor" costs, none of us could justify this stuff. But that being said, there can also be huge savings, If I eliminate my utility bills, that is a substantial amount of money, and how can you put a price on freedom, or peace of mind?
The general consensus on the forum (for CHP purposes) is approx. 1/3....1/3...1/3
Liquid cooled diesel:
1/3 lost as waste heat goes into the cooling system as potentially useable BTU's
1/3 lost as waste heat is lost in the exhaust gases (and is available for capture
1/3 becomes mechanical energy
veggie
Ok...back from hitting the books....Veggie, I go to my happy place whenever I hear consensus. I treat that word as evil, and immediately think of Ayn Rand's Howard Roark in Fountain Head...that said, In this case, it caused me to start referencing things.....here is something taken from Heat Engines Steam, Gas, Steam Turbines And Their Auxiliaries By John R. Allen and Joseph A. Bursley, second edition, McGraw-Hill Book Co. Inc. 1914....
"The following is a statement of the distribution of heat in a gas engine taken from actual tests and expressed in per cent.
Heat used in indicated work.................25 per cent.
Heat lost in exhaust............................37 per cent.
Heat lost in jacket water.....................33 per cent.
Heat lost in radiation and conduction......5 per cent."
And so I stand corrected. One third it is....
Forcodiesel,
As far as thermal efficiency.....the theoretical number is indeed easily obtainable if one has the compression ratio, and the ratio of the volume at cut-off to the clearance volume...or Vd/Vc....but this simply gives you the total work done...and as your definition of work seems to be a moving target, I would have to wait, and see what that is before I could comment further.
I seem to be in an odd place here, in that, I have boot strapped my off-grid lifestyle from the savings produced by living off-grid. As more of these off-grid systems come on line, the more capable I am of producing more off-grid systems. The economists out there, do not like to include food or fuel, in their inflation calculations. This seems so insane from an every-mans point of view, because he is unable to do without store bought food or fuel. One result of these off-grid projects has been my insulation from fuel prices because I simply don't buy enough of it to matter. So in one sense I do agree with the economists when they say that inflation is fairly low. The point of this is that your heat recovery scheme IS justifiable and will result in an economic benefit, if its done sanely. Given the 1/3 number, I would argue that it is much less expensive to simply plumb in a gas to liquid heat exchanger to the engine exhaust and grab those BTUs immediately.
My best friend wanted a raised bed garden...so rather then buy topsoil by the bag, he built a backhoe, to excavate the soil on his property, then he built a conveyor, and a gravel screen/shaker. All out of obtainium, over a period of about six years. I had fun helping him with some of my junk, and when we made castings for the conveyor and shaker gear box. So...I do absolutely understand the joy of building these seemingly outlandish projects, and have fallen victim to them myself (I enjoy making fuel processors).
I do protest from my armchair, that a test of the available heat (and noise) should be your first consideration. The presumption being that if the return is marginal, then the resulting effort should be marginal.
DF
DF,
I too find it silly that the government excludes fuel prices from the inflation mix.
Especially when oil went to $147 per barrel.
One possible explanation is that the rising costs of fuels automatically work their way into the cost of other goods due to rising material and transport costs stemming from the higher oil prices. ?? ... Not sure.
When evaluating off-grid economics for heating (in regards to CHP heat capture), the numbers change considerably if the fuel costs are almost eliminated. EG: Waste vegetable oils or other waste/renewables. For those who have a steady supply of such fuels, the CHP model can make economic sense.
Then there's the "hobby factor". If a hobby can provide energy and happiness, the economics, while still important are a bit less of a factor. :)
Example:
A typical 6HP Listeroid running at 80% load (or 4.8hp)
4HP =
Rule of thumb... 4.8HP makes 2.4kw electrical energy from the generator.
2.4 kw generator power connected to a resistance heater: : 8,195 btu/hr heat
Cooling system rejects 2,544btu/HP X 4.8HP : 12,200 btu/hr heat
Exhaust system rejects 12,200 btu/hr X 60% effy heat exch. : 7,320 btu/hr
===============
Total Available Heat: 27,715 btu/hr (from a modest 6HP engine)
These numbers will vary base upon the efficiency of each of the heat capture methods but the general idea is demonstrated.
One also has to factor-in the wear and service of the mechanical components.
If the fuel is near-free of costs, the CHP model seems to be a viable contender for off grid energy.
IMHO, the big draw of the CHP model is that multiple types of energy are produced. So if less heat is required, the electrical energy can be diverted to battery banks, lighting, or other electrical needs.
cheers,
veggie
Dear Veggie,
Wow! We were just having this discussion a few hours ago....or something like it. If one removes food and fuel from the consumer price index, or any other metric, that shows the cost of core goods, then a lot of "noise" is removed from the data. Economists are always looking for a good, or service that is immune from price fluctuations. Or something that is the same through out time...like we cannot really look at the cost of babbit bearings for a steam engine, but maybe a service, like a hair cut. So if one can take out the noisy data points, then a more accurate picture of the value of US currency can be found throughout time. These semantics are all for the purpose of finding out what the inflation rate is...it has absolutely nothing to do with actual people or the pain they feel when their money doesn't work. Inflation, is only the difference in the value of the currency.
One interesting aspect of the biodiesel I make here, is that it simply doesn't work in a Beckett oil gun. Yet, it works fine in an engine...so if I was to consider a CHP project it would be because I couldn't get any more of those pot oil burners from the 1930s. Those heaters actually will burn biodiesel without any life support. Like Steve's place, this is a rather unique situation though....even with grid power...things have to be "hammer simple" to coin a friend's phrase. The trade with the heaters are that they require constant removal of the coke that builds up, which is simply too much for most folks.
All a moot point this year, as I just returned from the oil shed, where I had to shovel down to the door, to retrieve a cubie of glycerine. We got 110 inches of snow so far, and if you don't have your heating scheme already lined up....well its just not happening.
I do support all forms of alternative energy...I think the more one experiments with it, the better understanding one has, even with a few failures (I am remembering my SVO days, and that stupid water injection idea....), and that promotes the ultimate fit for an individual's needs. I don't believe one size fits all...that only happens when you are sittiing on a few billion gallons of oil.
Back in the day, I would have told Focodiesel to simply go get a watercooled engine...engines were everywhere, most for free, before 2008. Now, hmmmm, a guy has to make do with whats out there. Schlimm Pickens!
DF
Well guys in an appeal to limited time, and just the fact that there was a changfa s1100an genset locally on craigslist, I will not be trying to convert a yanmar clone to water cooled, at least not in the near future. I still do like these little yanclones and see myself repowering all kinds of lawn tractors and other portable power units with them though. Great little engines for what they are, a light, air cooled, affordable engine.
Anyways I started a new post to get your opinions, and to document the build of my chp system utilizing my new water cooled changfa. Please go to the "Members Projects" section and check out "s1100an changfa, chp, variable speed/output build thread" or just click here: http://www.microcogen.info/index.php?topic=3264.0
Thanks,
-Focodiesel