ASMART":1is6pfvu said:
The quick answer: I'm a stubborn sort of guy and like to work with what I have, so I'm trying to get carby technology to work rather than the fuel injection. (if i had a EFI car I'd tinker with that in mind) You are 100% correct to say that the fuel injection might be the better way to go. Under pressure, the fuel remains liquid, then some will flash as soon as it is injected into vacuum. However, some of the lighter fuel components eg. Pentane will still want to go to vapour even at 5bar pressure at the max temp of the coolant. Not sure what the fuel pressure in a normal EFI set up is but I seem to remember hearing something in the order of 40psi is about the mark. (can someone tell me more??) If you get vapourisation in the injector, you may well hit the same problem if too much fuel flashed off in a carby. You could get around this by lowering the temp to which you heated the fuel. By splitting the fuel into light and heavy fractions it might be able to successfully meter the fuel with out hitting the vapour lock problems that occur with normal fuel. It just means having two temperature settings for the two fuel fractions. Minimal heat for the light fraction, max coolant temp for the heavy fraction........its a theory anyway.
Regards,
Teddy
i assume you have read my recent post about using molten solder instead of an oil. the only problem, naturally, is that while heating up it will take a significant amount of time to pass the melting point. thanks for looking!Stubby":13mc8qym said:
i disagree with your logic. yes, it is more difficult to meter as a vapor. but consider this: ever since the days of Christ, people have been using various forms of heated intakes to improve fuel atomization/vaporization with small (1-3mpg) gains. consider that half of the regular fuel used by everyone should vaporize in such an application. a believe that your system will cause small mpg gains, but not enough to warrant the complexity of the system.dcook":13mc8qym said:
conventional 100mpg theory has always been superheated fuel
DONT LOSE HEART - the thoery IS possible, but only for people who have the dedication to finish a project
thats what im thinking too, his heated intake causes small gains, but the distillation has minimal effectASMART":13mc8qym said:
dccok, could you help us understand what benefit it would be to distill (vaporize then condense) your fuel before using it, im sure youve got logic here that we arent getting
teddy, i respect your attempt to maintain teh carby setup, but i believe that the way youre going about it will result in too much complexity. what seems best to me is to have the stock carby for warm-up until you can vaporize your fuel, then switching the fuel supply to your setup, and routing teh fuel through a valve (lets say a lawnmower-size carby) and into a vac port. call it throttle body injection, if you like. it wouldnt be hard to build a linkage from the carby (being used as a throttle body) to hte fuel valve and produce a simple metering device
thats all for now--josh
A
Anonymous
Guest
Yes, intakes have been heated for umpteen years, and that's a good thing. A hot intake manifold transfers heat to the air/fuel mixture helping to vaporize the gasoline. But this happens AFTER the air and fuel have been combined, at the appropriate ratio, in the carburetor.
My plan is to heat the intake, and the incoming air, so that when the air and fuel combine the fuel will absorb heat from the air and the intake and become a vapor, after the carburetor. This will simplify metering the fuel. It means rejetting the carb for the higher air temperature. (Higher temperature means less oxygen which means smaller jets are needed.)
If you heat the fuel to 450 degress, and then mix it with air less than 450 degress, you will condense some of your fuel.
Why do I want to vaporize the fuel and then condense it? This will take a lot to explain.
Gasoline is a mixture of different hydrocarbons. Some will vaporize at much lower temperatures than others, as can be seen in Teddy's post. Liquid gasoline doesn't burn. Only when it is in a vapor state does it burn. Its important not to confuse a mist with a vapor. When the fuel and air mix in the venturi of the carburetor, the lighter hydrocarbons become a vapor and the heavier are in the form of a mist. This mixture is drawn into the cylinder, compressed and then ignited by the spark plug. But only the vapors ignite. So the lighter hydrocarbons start to burn. But the lighter hydrocarbons don't all start burning at once. The flame has to spread from the spark plug across the combustion chamber. As the fuel burns, it creates enough heat to vaporize more hydrocarbons and the flame travels . Because some of the hydrocarbons have to absorb some of the heat in order to vaporize, they slow down the flame travel. Its very complex. The lighter hydrocarbons start burning, creating heat which is being transformed into power, but some of the heat is being absorbed by the liquid fuel, which slows down the burn. Also, the heat created by the lighter hydrocarbons is not necessarily enough to ignite the full spectrum of hydrocarbons, but only those slightly heavier, but as the slightly heavier start to burn and create heat, they ignite the slightly heavier, and so on. Its like a chain reaction. Heat continues to push down on the piston, and liquid hydrocarbons continue absorb heat, vaporize and burn. This process takes only a fraction of a second, but thats too long. The burning process continues long after it could have been useful to make power. Instead the heat goes out the tailpipe or the radiator.
During the burning process, the liquid fuel is absorbing heat. This keeps the temperature at an acceptable level. If we lean out the mixture too much, the temperature in the cylinder starts to rise. This can lead to detonation, also known as ping. Detonation can lead to pre-ignition.
So why do I want to vaporize the fuel and then condense it?
My goal is to only use that part of the fuel that I can fully vaporize with heated air. A fully vaporized fuel eliminates everything I described above. The flame travels EXTREMELY fast. This means nearly all of the fuel is utilized as power, instead of the 20-30 percent that is estimated to be used by todays engines. Not only do you eliminate the late burning fuel, and the excessive heat, the fast burn allows you to reduce you ignition timing, eliminating a lot more waste.
An alternative to separating out the lighter ends would be to have a very long run of intake manifold that would have time to heat the air/fuel mixture to the point that the entire mixture was vaporized. In the 70's a guy took a Ford LTD and put something that resembled a carb on the gas tank and heated the mixture all the way to the engine. This is documented by the press. He got over 100 mpg.
Holley Carburetor Company started making carburetors back in 1905 – 1910 range that would vaporize kerosine so that a gasoline engine would run on it. One was for sale on E-bay about a year ago. I kick myself in the butt for not buying it. It went cheap. I think for under $200. I did buy the owners manual for that carb.
Fast burn is the key to fuel mileage and power.
soryy for the length of response,
dean
My plan is to heat the intake, and the incoming air, so that when the air and fuel combine the fuel will absorb heat from the air and the intake and become a vapor, after the carburetor. This will simplify metering the fuel. It means rejetting the carb for the higher air temperature. (Higher temperature means less oxygen which means smaller jets are needed.)
If you heat the fuel to 450 degress, and then mix it with air less than 450 degress, you will condense some of your fuel.
Why do I want to vaporize the fuel and then condense it? This will take a lot to explain.
Gasoline is a mixture of different hydrocarbons. Some will vaporize at much lower temperatures than others, as can be seen in Teddy's post. Liquid gasoline doesn't burn. Only when it is in a vapor state does it burn. Its important not to confuse a mist with a vapor. When the fuel and air mix in the venturi of the carburetor, the lighter hydrocarbons become a vapor and the heavier are in the form of a mist. This mixture is drawn into the cylinder, compressed and then ignited by the spark plug. But only the vapors ignite. So the lighter hydrocarbons start to burn. But the lighter hydrocarbons don't all start burning at once. The flame has to spread from the spark plug across the combustion chamber. As the fuel burns, it creates enough heat to vaporize more hydrocarbons and the flame travels . Because some of the hydrocarbons have to absorb some of the heat in order to vaporize, they slow down the flame travel. Its very complex. The lighter hydrocarbons start burning, creating heat which is being transformed into power, but some of the heat is being absorbed by the liquid fuel, which slows down the burn. Also, the heat created by the lighter hydrocarbons is not necessarily enough to ignite the full spectrum of hydrocarbons, but only those slightly heavier, but as the slightly heavier start to burn and create heat, they ignite the slightly heavier, and so on. Its like a chain reaction. Heat continues to push down on the piston, and liquid hydrocarbons continue absorb heat, vaporize and burn. This process takes only a fraction of a second, but thats too long. The burning process continues long after it could have been useful to make power. Instead the heat goes out the tailpipe or the radiator.
During the burning process, the liquid fuel is absorbing heat. This keeps the temperature at an acceptable level. If we lean out the mixture too much, the temperature in the cylinder starts to rise. This can lead to detonation, also known as ping. Detonation can lead to pre-ignition.
So why do I want to vaporize the fuel and then condense it?
My goal is to only use that part of the fuel that I can fully vaporize with heated air. A fully vaporized fuel eliminates everything I described above. The flame travels EXTREMELY fast. This means nearly all of the fuel is utilized as power, instead of the 20-30 percent that is estimated to be used by todays engines. Not only do you eliminate the late burning fuel, and the excessive heat, the fast burn allows you to reduce you ignition timing, eliminating a lot more waste.
An alternative to separating out the lighter ends would be to have a very long run of intake manifold that would have time to heat the air/fuel mixture to the point that the entire mixture was vaporized. In the 70's a guy took a Ford LTD and put something that resembled a carb on the gas tank and heated the mixture all the way to the engine. This is documented by the press. He got over 100 mpg.
Holley Carburetor Company started making carburetors back in 1905 – 1910 range that would vaporize kerosine so that a gasoline engine would run on it. One was for sale on E-bay about a year ago. I kick myself in the butt for not buying it. It went cheap. I think for under $200. I did buy the owners manual for that carb.
Fast burn is the key to fuel mileage and power.
soryy for the length of response,
dean
There are some low melting point metals available from MSC Industrial Sup. I think they go as low as 117 or 158. They are expensive.
http://www1.mscdirect.com/CGI/N2DRVSH?S ... 349&SIOR=1
http://www1.mscdirect.com/CGI/N2DRVSH?S ... 349&SIOR=1
dcook":38zutgaq said:
This is starting to sound familiar. Not that I know of the above test, but that we're getting awfully close to the technology I've talked of in previous posts refering to the Aussie inventer who fully vapourised the fuel by heating the air to above 200°C. What it essentially seems to come down to is effective heat transfer between the exhaust gases and the incomming air. To do this comes down to designing a very efficient, yet compact heat exchanger (HEX). You are basically transfering heat from a gas to a gas, meaning that the heat transfer will be rather sluggish. Gas does not heat up another gas very well, especially when separated by a metal wall in the HEX. The way to get around this is to have as much heat transfer area in the HEX as possible. If you're using metal tubes within another container, that might mean a lot of small tubes with multiple passes in the one container. Personally, I like the either spiral or compact plate HEX's to offer the needed heat transfer area.
I've heard of heating the entire air/fuel mix to vapourise all the fuel before, but the inherent danger in that is if it ignites and flashes back the force and pressure created can do a LOT of damage. But it offers the easiest solution when it comes to metering the fuel through a carby, because no changes are required. The air is still at ambient when it enters the carby. One solution to the potential dangerous situation is to borrow a piece of equipment from the petrochem industry: in-line flame arresters. Basically either steel wool, or other such material to prevent a flame front from passing that point where it is installed. The steel wool absorbs most of the heat from the flame front so that the flames are put out. But during normal operations, the steel wool is 'open' enough to allow for easy passage of gases. There are a lot of designs for these devices out there, it might be a matter of putting something like this into the line that feeds the motor so nothing can burn back to the carby.
More ideas, more things to think about. Wish I had the time and money at the moment to actually build and test a few of these ideas. For the moment I'm restricted to theorising and calculations, just need the next step to experimentation.
Teddy
thanks for those! now ive got the MSC big book sitting on my deskStubby":2imnsl56 said:
naturally, at $40 or $110 / pound, they are a little steep, especially when solder is a couple bucks a pound, and the one we used melts not too much higher.i'll just say that the worst case of a backfire blowing up a tailpipe doesnt even compare to the damage that would result. as for the flame arrestors, while they have some value, they fail to protect the explosive mixture from blowing up its pipe, which would probably destroy the car. in the name of safety, i'm starting to think in terms of having a superheated air intake with air, and also a superheated fuel system, such that the fuel and air only mix in teh manifold.teddy":2imnsl56 said:
i aint saying that anything is a bad idea, i'm just trying to find a safer idea
--josh
pickupman":35p3vpes said:
Would probably be similar to the explosive material we set off at work a few weeks back.....lots of damage to pipes that contained the explosive material. Hence something worth avoiding.
Heres where fuel injection comes into its own. Superheat the air as hot as possible, heat the fuel (using engine coolant) as far as possible without causing probs for the injectors, then let the engine computer manage the air fuel ratio as its measuring O2 at the exhaust. Probably the better way to go. That way (especially if you have an injector in each runner) the fuel and air only meet at the last moment before entering the cylinders.
Teddy
A
Anonymous
Guest
My plan is to route a tube from the lines going into the heater core, and ziptie them to a section of fuel line close to my injectors. That way the fuel is heated to around 215 degrees right before it is injected into the runners on my manifold. The EFI fuel pressure is between 40-50 psi, therefore, the heated fuel would resist vaporization until it was decompressed during injection. Would a "cold air intake" be good or bad in this situation? Also, would water injection add or detract from this. The gains in power and economy from water injection are widely noted, but would the cool air reverse the whole heated fuel aspect?
i believe that the cold air intake would not be a help in this application. our goal is hot fuel, and for the fuel to stay hot, it cant be mixed with cold air.BigPhill":21gqmcy5 said:
as for water injection, i assume it would be a good thing, just considering the facts here: water injection improves output because when the injected water vaporizes, it causes an extreme increase in volume/pressure, thus pushing down on teh piston with more force. i dont see any way htat it could oppose the vaporized fuel, thus i reckon it should be a help
thinking about your overall setup, there's one problem i see: many cars have suffered from a condition called vaporlock. this is when the fuel vaporizes before it reaches the injectors, thus preventing normal injector operation. i fear that you will stall out somewhere in the middle of the road almost as soon as the engine reaches operating temp.
well, let us know how it goes!
--josh
A
Anonymous
Guest
The water injection works just like a cold air intake in that it cools the air thus condensing it. So how would water injection benefit and not a cold air intake?
i was under the impression that water injection was a benefit because the water expands so much when it vaporizes (during combustion), thus resulting in a higher pressure. if i'm not mistaken, it has minimal effect until the mixture is ignited; a cold air intake cools the air before it mixes with the fuel, whereas teh water injection cools it only after it has been ignited.
does anybody with more experience have anything to add?
--josh
does anybody with more experience have anything to add?
--josh
Silver Shadow
Well-known member
water injection only cools the air/fuel mixture enough to slow the burn rate so to stop preignition. If you realy want to help the engine use low presure steam injection by letting the exhaust heat the water under vacume. Uses less water and gives more grunt, and maybe a little more mileage. Cold air, hot fuel/air to keep fuel/air mix in suspention. At 16.5 to 19 Miles per gallon of gas my square block (36 square feet of front wind pushing) running down the road is doing about it's best, unless I can reduce the frontal drag.
A
Anonymous
Guest
to re-energize a dead debate, about the only way I can see getting that kind of efficiency would be the ability to run the engine lean enough that it could be at or near full throttle to kill off the pumping loss past the throttle blades. some heating of the fuel might also be in order. Some other technologies might be necessary, too... slotting comes to mind...
A
Anonymous
Guest
This is fascinating - a re-play of "the blind men and the elephant", a long rambling, incoherent assortment of rumor, hearsay, non-sequitur and violation of the laws of physics.
I'd explain, it would take too long, but briefly: you can't get a car (Ford LTD) to 100 mpg even with 110% fuel energy recovery - frontal area + rolling resistance + weight X mph = NFW.
Really hot and lean mix burning near TDC will do something, but it won't be 100% conversion of heat to mechanical energy.
#1 reason why heating fuel increases mileage: it reduces the density of the fuel, an since a venturi can't compensate for this it leans mixture. Slight improvement over that other rocket science: smaller main jet.
There's a technical term for pre-heating fuel and air to 400 degrees - it's called a "bomb". The smallest static electricity or secondary voltage leak will put you on "film at 11".
I'd explain, it would take too long, but briefly: you can't get a car (Ford LTD) to 100 mpg even with 110% fuel energy recovery - frontal area + rolling resistance + weight X mph = NFW.
Really hot and lean mix burning near TDC will do something, but it won't be 100% conversion of heat to mechanical energy.
#1 reason why heating fuel increases mileage: it reduces the density of the fuel, an since a venturi can't compensate for this it leans mixture. Slight improvement over that other rocket science: smaller main jet.
There's a technical term for pre-heating fuel and air to 400 degrees - it's called a "bomb". The smallest static electricity or secondary voltage leak will put you on "film at 11".
I'll throw something out, what if one aquired a TBI setup, a spare heater core, and probably a seperate small electric pump.
For the setup I'm going to assume air will be drawn from someplace like the inner fender well.
Rig the heater core immediately after the air filter, which will be located very close to the fender well.
Immediately after the heater core place the TBI injection.
It's sort of like the van example with the carb on the gas tank, though a bit safer (I think at least), since it doesn't heat with exhaust gasses or rick getting smacked with something on the road. Hopefully theres plenty of length for a good portion of the fuel can vaporize, though probably not all of it. Fuel and air at 400 is agreeably bad. I don't think 180-200 would be bad though.
I'm still curious about heating the fuel with the coolant idea. I know vapor lock is an issue, I'm not sure that you'll have that issue while the engine is running, but when you shut the vehicle off, and the fuel just sits there in the nice hot environment, and no new fuel moving. My first thought was some sort of drain plug, but that can potentially let as much vapor in (if not more) than fuel vapor out, that and you'd almost be garunteed to loose fuel.
and yeah, 100 mpg is probably impossible.
Thought just as I was about to post:
At what temp does gasoline actually boil? Because it normally just evaporates into the air mix through the tiny droplets doesn't it?
if it just evaporates, as long as you keep it below it's boiling point, I don't think it would vaporize while being heated in the lines. There's nothing for it to evaporate into. AND having the lines at high pressure will help raise the boiling point as well.
For the setup I'm going to assume air will be drawn from someplace like the inner fender well.
Rig the heater core immediately after the air filter, which will be located very close to the fender well.
Immediately after the heater core place the TBI injection.
It's sort of like the van example with the carb on the gas tank, though a bit safer (I think at least), since it doesn't heat with exhaust gasses or rick getting smacked with something on the road. Hopefully theres plenty of length for a good portion of the fuel can vaporize, though probably not all of it. Fuel and air at 400 is agreeably bad. I don't think 180-200 would be bad though.
I'm still curious about heating the fuel with the coolant idea. I know vapor lock is an issue, I'm not sure that you'll have that issue while the engine is running, but when you shut the vehicle off, and the fuel just sits there in the nice hot environment, and no new fuel moving. My first thought was some sort of drain plug, but that can potentially let as much vapor in (if not more) than fuel vapor out, that and you'd almost be garunteed to loose fuel.
and yeah, 100 mpg is probably impossible.
Thought just as I was about to post:
At what temp does gasoline actually boil? Because it normally just evaporates into the air mix through the tiny droplets doesn't it?
if it just evaporates, as long as you keep it below it's boiling point, I don't think it would vaporize while being heated in the lines. There's nothing for it to evaporate into. AND having the lines at high pressure will help raise the boiling point as well.
well it doesnt have a single boiling point - because it is a mixture of many different compounds, some of it boils before other parts of it. the lightest parts have a boiling point somewhere around room temp, whereas the heaviest parts boil upwards of 400*. to illustate this, pour a little gas into an open container and come back to it next week. the part that remains will be some kind of sticky sludge. this is the part that boils around 400*.Leddemo":318gz87h said:
thats why its so difficult to vaporize it while keeping it at a safe temp.
A
Anonymous
Guest
http://www.agsint.com/conden.shl
This unit drops the boiling point because it vaporizes the fuel under vacuum. When you pressurize say, your water in the radiator, the boiling point rises. Thank goodness for radiator caps...The reverse happens when under vacuum.Thats why your coffee stays so hot in a thermos, the vacuum. This fuel vaporizer tees into the fuel line. When your foot is backed off the throttle a bit(such as cruising) and the engine vacuum is up, it pulls fuel and air (via pcv system) through a very small orfice inside the unit and it travels under that vacuum through 4ft of hose into the carb adapter plate or the manifold after the carb. The reason it works is simple. A carb and fuel injection meter raw wet fuel. This unit vaporizes it at lower temp better than a carb can. It does not hinder the carbs function and is unnoticable while driving. If you have a vacuum gauge while you drive you can see how your driving habits affect your mileage. your foot goes down and more air and fuel rushin to the opened up carb causing vacuum to drop. This unit only works when the engines vacuum is up. That is when the hose from the manifold is sucking on the unit. Burning vaporized gasoline is like running propane. The advantage is vaporized gas is much more powerful. This system is nice because you still have the power of your mondo carb at your toe tips. It does not vapor lock as some have told me it would have to. I just tell them "whatever, your loss, (moron)''. your carb is not trying to meter the vapor. The vapor heads right to the cylinder that is sucking it, after the carb. Vapor lock usually happens when you fuel is perculating in the lines. The unit also has a chamber for collecting the sludge blowing around in your crankcase. your oil stayes cleaner. My old man has been skrewing with these devices since the seventies. The one he was messing with the actually boiled the fuel (like a bomb). It was basicly a heat exchanger. Boiling fuel by running lines through the hot coolant water. Very dangerous should their be a leak. stainless is the best way to make that work. Anyway, when he found the fuel atomizer2000 about 9 years ago he bought it and we have paid for it many times over in fuel costs. I have had this on a 460 and a 390 and it doubles the mileage. The fuel companys do put stuff in the fuel to keep it from vaporizing. Marvel mystry oil helps put the properties back. Bikers and pilots have used mmo for years to fight detonation. They have redesigned the cold vapor system and the new 5000 looks better.I cant wait to get one..........
http://www.agsint.com/conden.shl
This unit drops the boiling point because it vaporizes the fuel under vacuum. When you pressurize say, your water in the radiator, the boiling point rises. Thank goodness for radiator caps...The reverse happens when under vacuum.Thats why your coffee stays so hot in a thermos, the vacuum. This fuel vaporizer tees into the fuel line. When your foot is backed off the throttle a bit(such as cruising) and the engine vacuum is up, it pulls fuel and air (via pcv system) through a very small orfice inside the unit and it travels under that vacuum through 4ft of hose into the carb adapter plate or the manifold after the carb. The reason it works is simple. A carb and fuel injection meter raw wet fuel. This unit vaporizes it at lower temp better than a carb can. It does not hinder the carbs function and is unnoticable while driving. If you have a vacuum gauge while you drive you can see how your driving habits affect your mileage. your foot goes down and more air and fuel rushin to the opened up carb causing vacuum to drop. This unit only works when the engines vacuum is up. That is when the hose from the manifold is sucking on the unit. Burning vaporized gasoline is like running propane. The advantage is vaporized gas is much more powerful. This system is nice because you still have the power of your mondo carb at your toe tips. It does not vapor lock as some have told me it would have to. I just tell them "whatever, your loss, (moron)''. your carb is not trying to meter the vapor. The vapor heads right to the cylinder that is sucking it, after the carb. Vapor lock usually happens when you fuel is perculating in the lines. The unit also has a chamber for collecting the sludge blowing around in your crankcase. your oil stayes cleaner. My old man has been skrewing with these devices since the seventies. The one he was messing with the actually boiled the fuel (like a bomb). It was basicly a heat exchanger. Boiling fuel by running lines through the hot coolant water. Very dangerous should their be a leak. stainless is the best way to make that work. Anyway, when he found the fuel atomizer2000 about 9 years ago he bought it and we have paid for it many times over in fuel costs. I have had this on a 460 and a 390 and it doubles the mileage. The fuel companys do put stuff in the fuel to keep it from vaporizing. Marvel mystry oil helps put the properties back. Bikers and pilots have used mmo for years to fight detonation. They have redesigned the cold vapor system and the new 5000 looks better.I cant wait to get one..........
http://www.agsint.com/conden.shl
A
Anonymous
Guest
Why not make an engine whose ignition system uses air injected into the cynlinder during compression. Just superheat the fuel and inject it, then when the compression is at it'sa highest, or whenever it's the best time, add the air probably with an air compressor and an air tank, maybe one for each cylinder. I don't know...pickupman":1b8bjfy3 said:
interesting thought, but doesn't it seem a little more sensible to inject a small volume of fuel to a large volume of air, instead of the other way around? but injecting superheated fuel vapors might be doableMumeral":3c8exxjp said:
