RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES
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RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/9/2007 10:57:53 PM

Posts: 2991
Joined: 1/23/2002
From: Arcen, , NETHERLANDS
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gentlemen, please!
Discussion of the importance of cetane value and-or what is ignition improver and cetane booster leads us nowhere, because our diesel combustion process is not nearly the same as in an injection engine, where the ignition sets in earlier with higher cetane values. I lack the knowledge to add 2 and 2 together it seems. For the moment My observation is thet I may need to go down to one drop per 10cc to one drop per 20cc, and see where that leads to
The ignition Improver I use contains 5-10% 2-ethyl hexyl nitrate, with balance peroleum oils and cleansing additives. This is not very much cetane booster, if you consider the price of 7 Euros for 250cc of the mix, with at best 25cc nitrate. Yet one drop of this booster mix to 10cc of fuel has a very marked effect on engine handling. My observations:
1) compression setting is reduced with added nitrate whilst
2) power stays the same and
3) needle and compression settings are more critical and
4) sustained running at lower ether content is realized.
5) Only minute amounts of 2-ethyl hexyl nitrate are needed for lowered compression settings
6) more ether means easier starting and handling in general.
7) more kero dilutes the castor oil more. The oil only is separated during combustion, but not in the crankcase.
8) exhaust residue with use of II in the fuel is corrosive as shown by a 12 hours room temperature copper test. (Very clear brown patina at oil contact surface)
9) In my test engine, I did not find any correlation between power and kero content. The 30% kero fuel had the same power as the 60% fuel, despite the fact that the high kero fuel contains more kiloJoules. The high kero fuel being very much harder to adlust well

< Message edited by pe reivers -- 8/9/2007 11:09:20 PM >

_____________________________

Pe, Dealer for MVVS, MTW and Mejzlik; www.mvvs.nl
There is sanctuary in analisys.

(in reply to slope-soarer)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/10/2007 3:12:23 PM

merugo

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From: rome, ITALY
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ugo

< Message edited by merugo -- 9/10/2007 4:07:23 PM >

(in reply to gkamysz)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/10/2007 4:27:55 PM

Posts: 1768
Joined: 6/24/2003
From: Crystal Lake, IL, USA
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quote:

ORIGINAL: merugo

Greg,
what a mix of concepts you have. Let's start from the very end, you speak of METHANOL. Do you know that methanol BOILS at 64°C while kero boils starting from 170°C up to 270°C? So methanol evaporates simply at the view of a running engine, if you don't keep the can close. Kero is a bit harder to vanish, it seems.

Why is this a problem for engines? I'm mean you must have evidence that this is truly a problem other than the simple notion that you think it doesn't evaporate. Yes methanol has a fairly low boiling point. What happens to the air when methanol is injected? I measured about 50°F manifold temperature on a four stoke glow engine on a 80°F day.

quote:

ORIGINAL: merugo
Since st. Thomas tested with his own hand, make this test, put on your right hand a few drops of methyl alchool. wait a little and go around shaking the hand of your boss , I guess he will notice nothing. The other day put a few drops of kero, wait the same little, than go shaking the same boss, than ask for your long waited pay rise .

This might be fun, but it doesn't apply to engines at all.

quote:

ORIGINAL: merugo
As for vaporization of fuels in HCCI, you forget that injection manifolds of these engines are regularly HEATED from 100°C up to 200°C ( obviously this generates a horrible amount of problems, first of all that of starting, since no ordinary battery can substain this load added to that of the starting motor)in order not to vaporize, since kero does not vaporize completely, but with the limited scope of making combustion happen at the right time before TDC.
The hope of having kero vaporized in HCCI remains a goal none reached yet, so the fuel there continues to burn in droplets. Leaning the mix seems to help, but NOx emissions seem to forbid this solution. I add that presently no model diesel engine can dream to go so lean as they (hope) to run future HCCI.

So what are the intake manifold and crankcase temperatures of model diesels? Maybe you have some data you'd care to share to persuade me to believe what you are trying to say.

You continue telling me how I'm breaking rules of science and I'll keep working on engines and running them.

_____________________________

Greg

(in reply to merugo)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/10/2007 7:40:18 PM

Posts: 226
Joined: 10/12/2004
From: Barrow in Furness, UNITED KINGDOM
Status: offline

quote:

ORIGINAL: pe reivers

gentlemen, please!
Discussion of the importance of cetane value and-or what is ignition improver and cetane booster leads us nowhere, because our diesel combustion process is not nearly the same as in an injection engine, where the ignition sets in earlier with higher cetane values. I lack the knowledge to add 2 and 2 together it seems. For the moment My observation is thet I may need to go down to one drop per 10cc to one drop per 20cc, and see where that leads to

7) more kero dilutes the castor oil more. The oil only is separated during combustion, but not in the crankcase.

Pe,
I agree, what we call it is not too relevant, as long as we understand what is happening.

I found out all the same things as you itemise. The only exception is No 7 (if you mean that reducing the ether a bit and then increasing the kero a bit dilutes the castor, then "7" is indeed correct)

I found that, unless SUFFICIENT ether is present then the castor will not mix with the kero.
There seems to be a minimum amount of ether needed to enable a certain percentage of castor to stay dissolved in the kero.

After some trial I established that 15% ether would allow the use of 25% castor and the oil would stay mixed. At higher temperatures the ether content could probably be dropped a few percent. Higher temperatures have not been common in the U.K this summer !

I initially made fuel with 10% ether and 25% castor content... it appeared O.K initially then went cloudy.
I added ether to give 12.5% and this looked O.K.... until a day or two later when I noticed it was cloudy.
After increasing the ether to 15% there was no further problems. I made and flew several batches of fuel with 15% ether and 25% castor... this mix performed very well.

It is nice to see that my results have been replicated by someone else as well.

(in reply to pe reivers)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/10/2007 7:42:49 PM

Posts: 226
Joined: 10/12/2004
From: Barrow in Furness, UNITED KINGDOM
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quote:

ORIGINAL: Motorboy

I learned out there are more oxygen in ignition improver who are due the engine will run smoother and powerful.

http://en.wikipedia.org/wiki/Peroxides
http://en.wikipedia.org/wiki/Nitrites
http://en.wikipedia.org/wiki/Methyl_ethyl_ketone_peroxide
http://en.wikipedia.org/wiki/Organic_peroxide

Thanks for the comments on ignition improvers Jens, I am going to have a look at those web sites in a minute.

(in reply to Motorboy)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/10/2007 7:58:07 PM

Posts: 226
Joined: 10/12/2004
From: Barrow in Furness, UNITED KINGDOM
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quote:

ORIGINAL: merugo

Sloper,
regarding the difference between those that say and feel and those that do, pls refer to posts no 834 and 835 at http://www.rcuniverse.com/forum/m_4561055/mpage_42/key_/tm.htm, that seems you have lost, there is a preliminary report of what I measured about modified and unmodified oil. No "feeling" involved since I reserve "feelings" to other matters, if possible.

Ugo

I don't need to refer to those posts as I had them in mind when I made my comments.
You have already done the testing yourself so what was to be gained by me doing it by means of a fairly primitive method ?

By refering to those who talk and those who do I was trying to drawout the distinction between....

The theorists..... a lot of talking, and making suggestions to others. Advice often seems to conflict with other known sources.

The doer's..... these are making fuels, even engines in some cases, and are doing actual testing and flying. By a series of slow, but steady, progressions we have made headway and discovered what works (and sometimes what doesn't ! )

The theorists seem to have advocated a lot of different alternatives BUT not actually put any of them into practise themselves. To have followed some constantly altering thinking would have had us jumping about like those Chinese fireworks.... the sort that come folded up together and "Flip Flop" all over the place.while making a lot of noise.

(in reply to merugo)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/10/2007 8:10:54 PM

merugo

Posts: 289
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From: rome, ITALY
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ugo

< Message edited by merugo -- 9/10/2007 3:52:36 PM >

(in reply to slope-soarer)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/10/2007 8:40:01 PM

Posts: 1717
Joined: 2/7/2004
From: Bergen, NORWAY
Status: online

Merugo, i am with gkamysz.

The carburator and intake canal works as a "freeze machine" due to gas velocity and vacuum make cold and still more colder with atomized fuel. There are not possible to evaporate the fuel inside by heat of surface such as in intake canal. After the fuelmix are entered in the crankcase, the gas will be expanded and make cold again under induction period by vacuum. The fuelmix get a bit heated up by crankcase compression, but not enough time to evaporate since there are still cold fuelmix inside. In fact are 3 thing who are entered in the cylinder after valve (4 stroke engine) / transfer port (2 stroke engine): fuelmix are allready evapored by heat by compression, liquid drops small diameter from 1/20 to 1/2 mm depent on carburator construction, a thinn fuelfilm at surface at canal before valve/transferport. With increased air temperature the mixture will be better such as in fair weather. Heat by piston will transfer heat to fuelmix under compression period before ignition starts (Now all know why the carbon must not be removed from piston in model diesel engine to improve running properties)

In fact the speed of gas are more higher than speed of hurricane!!!

How can it be possible the speed of gas are more higher than speed of hurricane?

Let us take the engine with bore at 18 mm and 16 mm stroke, also a .25 size engine and we are selecting the carburator with 5 mm diameter venturi to run the engine as diesel engine since we need more gas velocity to improve fuel atomizing cause the dieselfuel has higher viscosity than methanol/nitro for glowplug engine. The engine are running at 15000 rpm.
The result will show here:

1. Calculate piston speed in meter/second: 2 x 0.016 metre x 15000 rpm : 60 seconds = 8 meter/second

2. Calculate piston area and venturi area: Piston: 0,785 x 18mm x 18mm = 254,34 mm2, Venturi area: 0,785 x 5 mm x 5 mm = 19,625 mm2

3. Calculate speed of gas in meter/second: 8 meter/second x (254,34 mm2 : 19,625 mm2) = 103,68 meter/second (373,24 km/hour / 231.92 Miles/hour)

Also speed of gas are faster than speed of hurricane: 373,24 km/hour / 231.92 Miles/hour...

How big are vacuum inside in the engine under induction period.
1. Calculate vacuum in bar: (8 meter/second : 4) x (8 meter/second : 4) = 0,4 bar vacuum

There are enough vacuum to suck fuel from fueltank and make air more cold.

Formula from: Formeln für technische berechnungen by J. Phyl, 1980.

quote:

you forget that injection manifolds of these engines are regularly HEATED from 100°C up to 200°C

Merugo.. This is your own assertion.

In Peugeot 405 has manifold of plastic material with carburator and works well, there are not heated manifold by engine. The engine are receiving the heated air heated by exhaust to keep less cold fuelmix inside manifold in colder weather and are regulated by thermostat for hot/cold airmix before carburator. The plastic manifold was not hot when i took at the surface at manifold.
In modern car with petrol fuel injection are the shape inside cylinder head maked to improve turbulence of fuel/air mix make fuel smallere drops than direct atomized fuel from injector since there are not evapored fuel between fuel injector and induction valve. The heat of compression make fuel evapored before ignition starts.

Hot air/fuel (carb. or petrol injection) or hot air (dieselengine) in manifold will give bad cylinder filling cause not enough volume of oxygen, also the best to run the engine are airtemperature in manifold at 20 (with hot/cold regulated intake or fitted with intercooler togheter with turbocharger only)

Edit: Wrote some extra in last text.

< Message edited by Motorboy -- 8/10/2007 9:57:26 PM >

_____________________________

Jens Eirik
All landings are just controlled crashes!

(in reply to gkamysz)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/10/2007 8:43:29 PM

merugo

Posts: 289
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From: rome, ITALY
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ugo

< Message edited by merugo -- 9/10/2007 3:53:09 PM >

(in reply to Motorboy)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/11/2007 10:48:31 AM

merugo

Posts: 289
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From: rome, ITALY
Status: offline

ugo

< Message edited by merugo -- 9/10/2007 3:53:34 PM >

(in reply to merugo)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/11/2007 7:54:55 PM

merugo

Posts: 289
Joined: 12/13/2006
From: rome, ITALY
Status: offline

.
Ugo

< Message edited by merugo -- 9/10/2007 3:55:18 PM >

(in reply to merugo)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/11/2007 7:57:42 PM

Posts: 226
Joined: 10/12/2004
From: Barrow in Furness, UNITED KINGDOM
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quote:

ORIGINAL: merugo

Sloper
I was simply asking to try to asses by a very simple way if what you "feel", that is an appreciably higher viscosity of modified oil in front of an unmodified one (what I also wrongly "felt" before measuring) is true. This could have been of help to everyone.
When I made measurements on different olive oils I found that this marked increase does not happen.
From your strenuous defense of the (obvious) your right of not making also the most elementary objective comparative test, someone could doubt that yourself are doubting of what you affirm.
I remain absolutely indifferent to this since I have no valid reason from moving from my published conclusions until contrary proof. "The viscosities of modified and modified olive oil follow an unique line as drawn on the ASTM chart I reported a few replies before".
ugo

Ugo,
If you think that is a "strenuous defence" then you greatly underestimate me !

It is rather.... I thought the modified olive oil was more viscous than unmodified oil. I also thought it was more viscous than the car engine oil I use.

The modified olive oil and the mineral oil are perfectly satisfactory for my use. That's all I need to know. You have reputedly done the tests and are happy with the results that you observed on the olive oil that you tested. That is like saying I made some wine from white grapes and you can easily replicate my wonderful wine..... that implies that all white grapes are the same !

Straight away your "empirical" testing falls down. You would have to test many samples of different olive oils, both straight and modified in order to come up with a definitive answer.

I have devised, tested and used a fuel mix with lubricants that work for me.

Greg, Stewart, Chevy, Andy, myself and others have all come up with fuel mixes that work and do the job we ask. Whereas you, come up with plenty of different suggestions that others should try in their fuel mix. I don't see any signs of you putting your own theories to the actual test in an engine
.
If you have tested some of the ingredients that you have suggested to others.... then you have been remarkably reticent about the results.....

You are happy to test and quote the results, I am happy to observe and use the results of those observations.

I am completely indifferent as to your tests.... I USE it and I KNOW it works. I also intend to stick with the considered opinion of the two different bio-chemists who have stated that modifying the oil is the correct thing to do. You may think that there is no need to modify the oil... but what is your opinion worth ? We don't know is the simple answer.

I use the thickest appearing, extra virgin olive oil that I can find. Olive oil does vary in its viscosity judging by the numerous samples I have picked up and examined. Strangely... white grapes also vary markedly dependent on where and in what soil conditions they grow.

(in reply to merugo)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/11/2007 8:22:31 PM

merugo

Posts: 289
Joined: 12/13/2006
From: rome, ITALY
Status: offline

Ugo

< Message edited by merugo -- 9/10/2007 3:55:52 PM >

(in reply to slope-soarer)

RE: DIESEL FUELS, OILS, COMBUSTIBLES AND ADDITIVES - 8/11/2007 10:31:52 PM

Posts: 1717
Joined: 2/7/2004
From: Bergen, NORWAY
Status: online

quote:

ORIGINAL: merugo
Diesel motor oils have strong additives contrasting acidity, castor and ordinary motor oil have not. So this can lead to some corrosion.

Again your assertion. I has repaired a lot of vehicle diesel engines, never experienced rust inside the engine, too not in heavy truck engine who my father are working as truck driver and keep maintenance self at truck.

The motor oil must be claimed to:
Prevent rust
Lubricate
Keep parts cooled
Prevent gas leakage
Keep engine parts clean
Prevent ruin oil quality in other brands of motor oil if mixed togheter.

Pe Reivers..

Rust in engine are generated by ether/ignition improver.

Text from PAW instruction: AFTER USE (All Engines)

Run to full operating temperature, stop by cutting fuel supply, NEVER by throttle or choking. Leave piston at BOTTOM of stroke for three days to allow escape of acid combustion residues. For longer storage, inject oil into inlet and flick over a few times.

quote:

ORIGINAL: slope-soarer

Greg, Stewart, Chevy, Andy, myself and others have all come up with fuel mixes that work and do the job we ask. Whereas you, come up with plenty of different suggestions that others should try in their fuel mix. I don't see any signs of you putting your own theories to the actual test in an engine

Ugo..
Sure you do not has good economy to spend at fuel/oil products and worn out/damaging the modelengines and let us to take a test with the fuelmix you suggested then we can spend at fuel/oil products and worn out/damaging our own modelengine. No! In generaly you are utilizing all folks to hear at you to make a fuel test with their model engine instead to worn out/damaging your own modelengines.
We are not your test-rabbits!

You never had contributed who we can have use..
When you was here first time, you do not knew about autoignition, cetane number, etc, etc. Not real knowledge of the engine anatomy.. Remember you showed to links who are unuseful for our modeldiesel engine to example lighterfluid are igniting at a tiny spark and will ignite by heat of compression before i showed you the data sheet for lighterfluid to you. Some time you lied about test results (i discovered there was false test results since i am peugeot mechanic when you wrote about turpentine in peugeot engine cause engine code was not correct and loaned from other website). More more i can not write here since there are not place here...

To all members/nonmembers who are reading here: in doubt? Read all his post such as he wrote: give a try, if, quess, maybe etc etc.. Then you ( to members/nonmembers who has knowledge in own occupation) can estimate his knowledge.

You must change your attitude:
Never write nonsense test results or facts.
Never let/force other to try your test without you has tested with good and honest results.
Show the real test and practice , give photo, movie as evidence you has allready done.
Never write without you real know facts about engine, oil etc..
Listen to other who has knowledge or has a occupation as a specialist in his/her work and know to tell to you.
Better to be honest.

If not, you can not inspire confidence with us here.

Sorry, it is all i has wrote..

< Message edited by Motorboy -- 8/12/2007 7:20:33 AM >

_____________________________

Jens Eirik
All landings are just controlled crashes!

(in reply to slope-soarer)