03-02-2012, 03:52 PM
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#1 (permalink)
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oldschool
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HHO discussion (split off from the BSFC thread)
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Originally Posted by E4ODnut
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That is a good collection of information. I only noticed a couple of errors.
Like the BSFC maps, the emissions chart doesn't show the test load level or the relative spark advance
When you start the spark is more important in matching combustion speed with the piston speed than is the AFR, and the advance also has a significant effect on NOx in particular because of how much it effects combustion temperature.
A higher combustion temperature and pressure (up to the point of the detonation limit) is much more efficient than a lower combustion temperature, and in that way results in reduced BSFC and better fuel efficiency.
The mechanism by which this works is to speed up the burning of the air/fuel charge within a more mechanically advantageous range of the piston movement after TDC of the compression stroke.
The added heat energy during compression is what increases the burn speed.
Starting the spark earlier (before TDC compression) results in more heat and expanding gases created before peak compression.
The piston goes on to compress this hotter and more expanded charge that in turn adds significantly to the heat of the burning charge. Compression of charge adds heat energy. The dynamic compression goes up with increased spark advance. The temperature in the chamber goes up, even though EGT can often drop a bit due to less late burning in the exhaust port.
This higher temperature in the chamber exerts more force on the piston in the critical crank-to-rod angle that most efficiently transfers energy to the crankshaft. Making the speed of this expanding gas closely match the speed of the downward moving piston is the holy grail of engine tuning, for both power and economy.
Now that this subject is covered I feel the need to bring up something I have observed on various online forums, including this one.
Over and over I see far too many extremely knowledgeable and academically qualified individuals (perhaps armchair physicists) jump authoritatively into discussions concerning engine efficiency and the amount of fuel that is being burned during a given set of conditions in a running engine. These instances pop up often in discussions concerning the ability of HHO to effect a change in engine efficiency or fuel mileage, where the supposed "debunker" points to research data showing that less than 1% of fuel remains unburned as tested before the catalytic converter. The assumption being that there is not enough extra fuel to be better utilized during combustion in order to account for an increase in output or efficiency. The HHO proponents state their claim (incorrectly) that the HHO burns more of the fuel, and therefore increases fuel efficiency.
The % of fuel burned before the catalytic converter isn't the issue and never was.
What counts is WHEN the fuel is burned.
A tuner can change the output (BSFC) of the engine drastically by simply changing the spark advance and keeping all other variables the same.
If you take the "debunker's" claims as absolute reasoning, then every engine tuner out there has somehow broken the law of conservation of energy.
There are several ways to manipulate the burn-rate in the chamber, ranging from static/dynamic compression changes, fuel additives, cylinder head modifications, heat rejection rate, AFR, fuel additives, and more.
None of these violate any law of physics. The disconnect is that so many very knowledgeable people have an incomplete understanding of how the engine is actually working and even less understanding when it comes to manipulating it to effect meaningful changes beyond theory.
In power tuning N2O is used as an oxidizer to both allow extra fuel to be burned, and an increase in air/fuel burn-rate, both in order to increase power output. N2O is only 36% Oxygen by weight and in practice effects a drastic change in burn rate that requires an adjustment to the spark advance in order to stay within the physical limits of the system.
I'm pretty sure that HHO is around 88% Oxygen by weight, making it a very formidable oxidizer, and theoretically very little HHO mass would be required to effect a change in burn rate at a low engine RPM and VE.
To head off any incorrect speculation on this issue I'm going to state that yes you can add small amounts of N2O and drastically effect burn-rate without the addition of any extra fuel, so no, the use of an oxidizer does not necessitate extra fuel use, though many people have had problems with the factory adaptive fueling routine adding the extra fuel automatically.
I have yet to see this addressed correctly by either side of the discussion. I only used this example of the HHO discussion to point out where a lot of efficiency discussion gets fundamentally derailed by an apparent lack of understanding of the power transfer process as it happens in the combustion chamber.
This is something that fundamentally undermines the usefulness of many BSFC maps out there, and especially those that lack certain specifics about the operating parameters of the engine during the test.
BSFC can be changed on the fly by changing the engine management parameters, even by your driving style.
Any particular load cell on a BSFC map could represent a vehicle holding a steady speed, OR a vehicle accelerating depending on road conditions at the time. This shows that under identical calculated load conditions the piston speed can vary, and this the optimum tune will vary along with that.
Again, before incorrect speculation happens, I'm going to say that RPM is only representative of a given piston speed when measured at a steady state. You are rarely at a true steady state while driving, and thus there are significant changes (accelerations) in piston speed per each combustion event as engine load and power output constantly search for equilibrium.
For any given combustion event a falling average RPM of 2000 RPM will have a much slower piston speed than a rising average RPM of 2000 RPM.
This is another one of those obscure facts that a tuner must know to be successful at matching burn-rate to piston speed.
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03-02-2012, 04:31 PM
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#2 (permalink)
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Master EcoModder
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W/regard to your comments about "HHO", your point is well taken regarding ignition timing affecting engine efficiency, however no one who advocates such systems actually makes enough bubbles of gas to affect the engine efficiency at any realistic load, even if they are smart enough to change the mixture or spark advance. In fact, more bubbles of gas emanate from other orifices. :P
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03-02-2012, 08:05 PM
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#3 (permalink)
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A Legend in his Own Mind
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Quote:
Originally Posted by Olympiadis
Over and over I see far too many extremely knowledgeable and academically qualified individuals (perhaps armchair physicists) jump authoritatively into discussions concerning engine efficiency and the amount of fuel that is being burned during a given set of conditions in a running engine.
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John Heywood, arguably the best known authority on automotive combustion is one such person. He not an arm chair kinda guy, but does real tests with real engines.
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These instances pop up often in discussions concerning the ability of HHO to effect a change in engine efficiency or fuel mileage, where the supposed "debunker" points to research data showing that less than 1% of fuel remains unburned as tested before the catalytic converter.
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The HHO promoter claim that prompts these rebuttals goes like this: "15% to 25% of the fuel in the combustion chamber goes right out the tailpipe. HHO improves combustion (acting like a catalyst or oxidizer) to burn all the fuel."
Of course the 15% to 25% figures are wrong. But equally wrong is the idea that HHO acts as an oxidizer in any meaningful sense. HHO, which is really 2H2 + O2, is a stoichiometric mixture that, when burned, offers no additional oxygen to the combustion mixture. The infinitesimally small amount of O2 is used up in burning the infinitesimally small amount of H2.
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What counts is WHEN the fuel is burned.
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And HHO has no effect on combustion rate, because the amounts used are far too small to have any effect at all.
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A tuner can change the output (BSFC) of the engine drastically by simply changing the spark advance and keeping all other variables the same.
If you take the "debunker's" claims as absolute reasoning, then every engine tuner out there has somehow broken the law of conservation of energy.
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Hard to know what you are trying to say here. First, given factory optimized timing, (which varies continuously under control of the ECU) a tuner cannot make "drastic" changes in either BSFC or output (which are not the same thing). There are no evil automotive engineers working to make you use more fuel. Companies spend many millions to tune for an optimized mix of fuel economy, drivability and performance. But the fact that you can make small changes in power output by altering timing has absolutely nothing to do with conservation of energy.
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There are several ways to manipulate the burn-rate in the chamber, ranging from static/dynamic compression changes, fuel additives, cylinder head modifications, heat rejection rate, AFR, fuel additives, and more.
None of these violate any law of physics.
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I have never seen anyone claim that any of these violate the laws of physics. Nor have I seen anyone claim that adding meaningful amounts of H2, O2 or a combination of the two would in some way violate laws of physics.
Perhaps you are confused by the often (and correctly) cited fact that no spark ignition engine car engine produces electrical energy from its alternator at better than 20% overall efficiency from fuel tank to alternator output. An ounce of gasoline consumed from the tank gives you 1/5 oz of energy equivalent at the alternator. So where the "conservation of energy" or "laws of thermodynamics" concepts come into the discussion is for those HHO promoters who claim that the H2, when burned, adds "power" or replaces fuel, etc. If this were true, in other words if the H2 energy output were equal to the additional fuel to power the alternator, then the electrolysis process would need to more than be 500% efficient which is impossible due to the universal applicability of the concepts mentioned.
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I'm pretty sure that HHO is around 88% Oxygen by weight, making it a very formidable oxidizer, and theoretically very little HHO mass would be required to effect a change in burn rate at a low engine RPM and VE.
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There is no theory that suggests this. First, HHO is not a "formidable oxidizer", even when employed in large quantities (e.g. 30 -100 times more than produced by an HHO unit). This is for the reason previously mentioned: there is no excess oxygen. But more important is the fact that even at low RPM and loads, the amount of HHO generated is not enough to have any measurable effect. One liter per minute of steam and oxyhydrogen is typical for a good HHO unit. Of this, 1/3 liter is O2. A 2 liter engine at 1/3 throttle and 1500 rpm takes in 500 liters of air per minute. Of that, 21% is O2, so figure 100 liters of oxygen per minute. Adding 1/3 liter of O2 to 100 liters will have no measurable effect, let alone the 30%, 50%, 75%, improvements mentioned in the adds. Even the EPA-certified $25,000/day dynos used for fuel economy measurements cannot measure such small changes reliably.
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For any given combustion event a falling average RPM of 2000 RPM will have a much slower piston speed than a rising average RPM of 2000 RPM.
This is another one of those obscure facts that a tuner must know to be successful at matching burn-rate to piston speed.
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A "combustion event" in the usual parlance means one burn, taking place during the power stroke and lasting milliseconds. The ECU adapts very quickly, event by event, so that it makes little difference if the car is accelerating or pulling a constant rpm. When accelerating, the average piston speed changes almost imperceptible from one event to the next, because therre are only milliseconds between events. But during any given stroke, piston speed changes dramatically from 0 to max and back to 0.
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03-02-2012, 09:32 PM
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#4 (permalink)
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oldschool
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Quote:
Originally Posted by Ken Fry
Hard to know what you are trying to say here. First, given factory optimized timing, (which varies continuously under control of the ECU) a tuner cannot make "drastic" changes in either BSFC or output (which are not the same thing). There are no evil automotive engineers working to make you use more fuel. Companies spend many millions to tune for an optimized mix of fuel economy, drivability and performance.
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Obviously the "ads" about HHO you have read with the claims you cite are wrong. You sound as though you're trying hard to convince me and perhaps yourself as well.
If you yourself have done testing on an automotive engine with regard to scale of HHO production vs engine air demand, then I would be curious to see your results, beyond your calculated estimates of course. I have yet to test such a thing and the data may become useful to me in some other area of tuning.
I received a very thorough training concerning the conservation of energy as a sophomore in high-school (1982) which has always been useful to me in many areas of life, not just physics classes.
It is a law that has dominion over all that we know in a broad scope, but when applied to individual situations the caveat "in a closed system" must be applied for it to be fully reconciled in the accounting process.
What I see you doing here is what I have seen numerous times by the younger crowd of freshly trained physicists (not meaning you), and that is to target the alternator of the vehicle as the weak point, having such a poor energy conversion rating. And it's not that it matters if the alternator was in fact 100% efficient, because that was never the point, and I would never get drawn into such a red herring (at least I would hope). If it were a closed system with a 100% efficient alternator, then HHO could still not produce excess energy. As far as I'm concerned that was never worth arguing.
The glaring fact remains that an automotive engine is not a closed system due to the majority of chemical energy in the gasoline not being converted into usable motion.
That is exactly where my discussion of burn-rate comes into play. An improvement in fuel efficiency that comes from a slightly better energy conversion rate in the combustion chamber is completely separate and, depending on tuning specifics, can far outpace the quantity of energy lost to an inefficient charging system, no matter what that power may be used for.
IRT what I quoted from you above, you seem to be confused about how the adaptive spark algorithms are actually working. What makes me think this is that you more than allude to the idea that millions spend by automotive companies directly result in an "optimized mix of fuel economy, drivability and performance.". If what you're really saying is that the tune is a compromise for greatly varying climates and extreme levels of ineptitude by the drivers of the vehicles they sell, then you would be on the right track. Don't forget to throw in the requirement to maintain a specified window of emissions, - that's a big one.
The fact is that the spark advance is not optimized for even running at stoich, let alone a particular performance aspect. Every algorithm I've looked at for adaptive spark starts with one or more base tables that are quite conservative ( in the interest of longevity in the hands of many ), with table switching thresholds and spark modifiers based on feedback from a knock-sensor, - the purpose being to minimize engine damage in a variety of circumstances ranging from bad fuel, to towing, to malfunctions or mechanical issues. I have yet to see an algorithm that is programmed to increase the efficiency of the burn, or result in less fuel used.
If you own a vehicle with such an algorithm, then please post it here. I would find it quite interesting, and I welcome new input.
Also, in the scope of what I've seen personally, the adaptive spark logic and adaptive fuel logic operate separately and completely independently of each other. This precludes the possibility of the ECM/PCM automatically tuning for best economy. An engine tuner has to perform this task of combining feedback from both fuel and spark in order to optimize a tune. I may be wrong, but I feel that if you were a real tuner, then this would already have occurred to you by necessity.
There is also the fact that if the PCM were programmed with logic to optimize best economy, then it would be unable to remain within the specified window of emissions standards.
If you have been around skilled tuners for any amount of time, or in fact learned the skill yourself, then you would also know that the difference a tuner can make is much more significant than you suggest. If there wasn't a significant room for improvement, then what would be the point?
I was amused at your attempted straw-man, being the evil automotive engineers. The ones that are and have been gainfully employed by an automotive company are generally extremely competent and do a great job given the constraints imposed upon them. Let them work unbridled by government imposed regulation and they could surely impress us all.
Change your straw-man to the EPA and I'll bite.
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03-02-2012, 10:11 PM
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#5 (permalink)
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oldschool
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Quote:
Originally Posted by drmiller100
the cause is if the rpm is slowing down, typically MAP is relatively low. If the RPM is rising, then MAP is high, and the driver is trying to accelerate.
NOS makes no sense for better mileage. HHO makes no sense for better mileage, unless you are a unicorn salesman.
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Without quoting all of that, yes you just described how a main spark table is basically set up (MAP vs RPM). Basically it needs to be set up this way to avoid misfires and/or engine damage. That does not imply that it is optimized though.
As for that last comment, that is why I specified that an oxidizer can effectively be added without additional fuel.
We are not talking about how an oxidizer like N2O makes power. I have been doing that for a very very long time, but it is irrelevant to this discussion of efficiency.
Whenever you lean out the AFR, the effect in the chamber is similar to adding an oxidizer because the ratio of free O2 to fuel goes up. At first this will actually speed the burn rate and efficiency will improve. If you go further lean, then the burn rate will begin to drop off.
Many people do add spark advance at this point, but more often than not they go beyond what returns the best fuel mileage.
Very high spark advance combined with a very lean AFR will make for an extremely load-sensitive engine that IMO will have an unacceptable number of misfires during normal driving, even when not outright stumbling.
This effect comes back to the reality of spark advance as a tuning tool in general. As you use advance to improve one end of the scale, you begin to pay for it at the other end of the scale. More energy is lost during the compression stroke with a lot of advance. This means you can only go so far with the starting the burn sooner before diminishing returns sets in. At that point you need to either change the characteristics of the fuel or the combustion chamber.
An oxidizer speeds the combustion process, which allows you to start the spark later in the cycle (not sooner), so besides a better energy conversion in the chamber, you also get less energy lost on the compression stroke.
A relatively small amount of oxidizer does not need extra gasoline in order to improve the burn in the chamber. In the heat of combustion the O2 will combine with H or C, or even other elements such as the aluminum that makes up the chamber surfaces. The point isn't so much what it ends up being combined with by the time it reaches the exhaust, but when it does its combining, and how many times during the critical window that increases energy transferred to the piston. With the use of an oxidizer there will surely be more free O2 leaving in the exhaust, but to assume that it just breezed through the chamber without affecting the burn is naive.
If you really have this belief, then I ask you to please set up an experiment with a small sacrificial engine. An oxidizer is easily purchased in the form of O2 or N2O. Put a wideband O2 sensor and a K-type thermocouple in the exhaust. Make sure your AFR starts out at the chemically perfect 14.6:1 ratio, make your observations as complete as possible, then add your oxidizer. Note everything that happens from rise in RPM, to the visual condition of the combustion chamber and spark plug upon tear-down.
If you have a way to measure a fixed partial-load power output, then all the better.
I can only share results that I have collected and highly encourage you to collect your own. There's no substitute for learning by doing. Yes you can absorb spoon-fed information, but it's not the same impact, and is often done too selectively.
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03-03-2012, 02:16 AM
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#6 (permalink)
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A Legend in his Own Mind
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Quote:
Originally Posted by Olympiadis
You sound as though you're trying hard to convince me and perhaps yourself as well.
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No, I rarely try to convince HHO promoters (or those who put forth magic as possibilities for how HHO might work) of anything. It's a loosing battle. They typically have little or no understanding of engineering or science, and operate only on belief. One might just as well be arguing religion.
It is for the benefit of the others, the ones who can be reached through reason that I debunk this stuff.
John Heywood is not one of "the younger crowd of freshly trained physicists". The nobel prize winning physicist who testfied for the FTC against Dennis Lee (the famous HHO promoter) was also not one of these fresh new physicists you seem to hold in disdain. Nor, of course, am I, particularly given that I had been teaching for more than a decade before you took your first physics course. While you were in high school, I was consulting with Ford Motor Company on methods to prepare their engineers for the rapidly increasing use of electronics in all automotive systems -- it was no longer going to be good enough for mechanical engineers to be just mechanical engineers.
The reason I rebutted your contention that HHO serves as an oxidizer, is that such assertions, which are not based on the science involved, only drag down the level of discourse, making this site less usable. Such assertions belong in the Unicorn Corral. If you want to make outlandish assertions there, so be it. But here, it just dilutes useful info with fairy dust.
Your accelerant theory has been advanced hundreds of times in the past. And no, it does not work that way. Sorry, I am not going to believe that my own training as a chemical engineer was for naught, that John Heywood is dim witted, but you are right. Your oxidizer theory is wrong: HHO is not an oxidizer. It is also not an accelerant when used in the microscopic quantities produced by HHO units.
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What I see you doing here is what I have seen numerous times by the younger crowd of freshly trained physicists (not meaning you), and that is to target the alternator of the vehicle as the weak point, having such a poor energy conversion rating.
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You have also misread the alternator issue. Alternators are 55% efficient on average according to Delco, although I have tested a few that are somewhat more efficient. Engines are no better than 25 percent efficient when operating in actual drive cycles. The "typical" figure often cited is lower. (If you run cars through the EPA drive cycles in a computer model you can verify that even the Prius does not have an average efficiency above 25%.) So if you want 100 watt hours out of a car's alternator, you must put in 100 / (.55 x .25) = 727 watt hour's worth of gasoline. Then you use the alternator output energy to produce hydrogen at 50% efficiency, so you get 50 watt hours worth of hydrogen for 727 watt hours worth of gasoline input to the system.
When people say that automotive alternators convert fuel to electricity at 20% efficiency, (implying the requirement for and impossible 500% efficiency in electrolysis to just break even) they are giving the HHO promoters the benefit of the doubt.
You've misinterpreted the meaning of a closed system. See the Delco paper in which they use 21% efficiency even in truck engines (of substantially higher efficiency than car engines). These energy balance analyses of sequential systems are very common.
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If you yourself have done testing on an automotive engine with regard to scale of HHO production vs engine air demand, then I would be curious to see your results, beyond your calculated estimates of course. I have yet to test such a thing and the data may become useful to me in some other area of tuning.
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Yes I have done testing of combined duct oxyhydrogen units. Such units, supplied by electricity from the wall, have been used in engine research, as a convenient method for producing hydrogen. Before you were born, I built a battery powered unit, (larger than the typical car unit) that could supply enough hydrogen to allow a lawn mower engine to continue to run at idle. The energy to run the lawnmower engine came from the battery of course, and the hydrogen was a low-efficiency carrier of that energy. Just running an electric motor from the battery would have been about 10 times as efficient. The battery was actually 2) 6V golf car batteries.
But beyond that parlor trick, no, of course I haven't run dyno tests on HHO units. What an incredible waste of time. Do you not already know how much air a given engine takes in? We know what the HHO units put out, from the claims of the promoters, and from the chemistry.
John Heywood can do the dyno tests and get paid for it. And of course the HHO units do not work -- he showed that convincingly. No one has ever advanced a plausible reason for why they should work, and no independent testing has ever shown them to work. If there were some plausible reason why they might work, then you'd see some research.
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The glaring fact remains that an automotive engine is not a closed system due to the majority of chemical energy in the gasoline not being converted into usable motion.
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You are confused on the meaning of a closed system. The fact that an engine runs at low efficiency does not mean that you cannot consider it a closed system for the purposes of thermodynamic analyses. When we say that and engine is 25% efficient, we are saying that 25% of the energy value of the fuel shows up as mechanical work.
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That is exactly where my discussion of burn-rate comes into play. An improvement in fuel efficiency that comes from a slightly better energy conversion rate in the combustion chamber is completely separate and, depending on tuning specifics, can far outpace the quantity of energy lost to an inefficient charging system, no matter what that power may be used for.
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You are conflating two issues. And creating fiction to support one. 1. HHO promoters often claim that the hydrogen comes, energetically "for free," that the alternator does not have to do work to supply the electricity for electrolysis. That is obviously incorrect -- we've been over the numbers above. 2. Changes in burn rate due to HHO is a fiction. HHO is not an oxidizer. It is also not an accelerant in the microscopically small quantities supplied -- even if you take the promoters 1 Lpm claims at face value. If you increase the amounts by about 100 fold, then changes in combustion can show up. However, even then the base fuel mixture must be very lean.
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I have yet to see an algorithm that is programmed to increase the efficiency of the burn, or result in less fuel used.
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You have not looked far. Every car with an integrated engine management system does this. Obviously economy is balanced with emissions, but it has to be, just as it has to be balanced with durability, performance, etc.
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Also, in the scope of what I've seen personally, the adaptive spark logic and adaptive fuel logic operate separately and completely independently of each other. This precludes the possibility of the ECM/PCM automatically tuning for best economy.
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Integrated engine management systems have been the norm for decades. This is from the Wikipedia article on the Bosch Motronic system:
Motronic is the trade name given to a range of digital engine-management systems developed by Robert Bosch GmbH (commonly known as Bosch). The unique feature of these systems, compared with their predecessors, is combined control of fuel and spark in a single unit. By controlling fuel and spark together, many aspects of the engine's characteristics (such as power, fuel efficiency, driveability and emissions) can be improved.
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03-03-2012, 04:37 PM
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#7 (permalink)
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oldschool
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Quote:
Originally Posted by Ken Fry
No, I rarely try to convince HHO promoters (or those who put forth magic as possibilities for how HHO might work) of anything. It's a loosing battle. They typically have little or no understanding of engineering or science, and operate only on belief. One might just as well be arguing religion.
It is for the benefit of the others, the ones who can be reached through reason that I debunk this stuff.
John Heywood is not one of "the younger crowd of freshly trained physicists". The nobel prize winning physicist
You've misinterpreted the meaning of a closed system. See the Delco paper in which they use 21% efficiency even in truck engines (of substantially higher efficiency than car engines). These energy balance analyses of sequential systems are very common.
But beyond that parlor trick, no, of course I haven't run dyno tests on HHO units. What an incredible waste of time.
You are confused on the meaning of a closed system. The fact that an engine runs at low efficiency does not mean that you cannot consider it a closed system for the purposes of thermodynamic analyses. When we say that and engine is 25% efficient, we are saying that 25% of the energy value of the fuel shows up as mechanical work.
You are conflating two issues. And creating fiction to support one. 1. HHO promoters often claim that the hydrogen comes, energetically "for free," that the alternator does not have to do work to supply the electricity for electrolysis. That is obviously incorrect -- we've been over the numbers above. 2. Changes in burn rate due to HHO is a fiction. HHO is not an oxidizer. It is also not an accelerant in the microscopically small quantities supplied -- even if you take the promoters 1 Lpm claims at face value. If you increase the amounts by about 100 fold, then changes in combustion can show up. However, even then the base fuel mixture must be very lean.
You have not looked far. Every car with an integrated engine management system does this.
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Assuming you have at least average reading comprehension skills, you must have skipped over several of my points made earlier, and you have went on to waste your time trying to re-explain things like alternator efficiency, while continuing on what seems to be a tunnel-visioned crusade of yours to brow-beat anyone who even brings up the term "HHO", even when just citing for example.
You surely must be misusing the term "closed system" when referencing a type of test measuring energy conversion improvement by way of an added oxidizer. Your "parlor trick" of running a small engine completely from HHO was in fact closer to a closed system in that context of how you do you energy accounting.
Clearly the enhancement of a gasoline engine by the addition of an oxidizer is no longer a closed system in the same context. If you were to treat it as a closed system when accounting for all of the energy involved then you would end up with simply a low total % of energy conversion to motion rate vs a slightly different, but very low % of energy conversion rate at the end. This would not even begin to imply any sort of "fiction" or "fairy dust". It is only a reasonable "thermodynamic analysis" as you put it. It would take into account the proportion of the total chemical energy contained in all of the gasoline involved, and all of the chemical energy contained in additive involved vs the energy actually converted into movement.
A clue that signals a change in energy conversion rate would be a measured change in EGT when adding the oxidizer of your choice. This change in EGT has been observed in many engine tests, to include those with only tuning changes and not the addition of an oxidizer. There's nothing fictional about it.
Did you not observe a change in EGT when you were doing your test with HHO, or magic fairy dust, - you know, back before I was born?
If for some strange reason you lacked the proper experience or testing equipment back then to obtain any useful data besides "it doesn't work", then there is the opportunity to observe similar experiments today, even on youtube. What I have observed on the youtube videos is that when gasoline is completely substituted with HHO for a small engine test, with no other changes, the engine runs, but then develops a high rate of backfires where the gasoline did not backfire. For myself and other experienced engine tuners, this is proof enough that the burn rate and thermal conversion rate has changed significantly. This is to be expected when either changing the fuel composition, or enhancing it by way of another fuel type or an oxidizer.
I'm not trying to qualify a backyard youtube video as a true controlled scientific analysis. No, but an observation is an observation and does have some worth.
When the burn rate of a fuel is changed, it then requires a change in the tune and/or mechanical changes in the engine design in order to optimize whatever aspect you want to improve, to include BSFC. This is no more or less than common knowledge, at least in the engine tuning community.
Now for a bit of wild speculation on my part about your extreme perspective in this area. Perhaps when you did your first HHO type experiment as a youngster you were actually still a student and intended to use this experiment as something grade-able by your professor. If so, then how could you go wrong by showing that there is a very high percentage of energy lost at every step of multiple conversion methods? A professor might be impressed with such a validation of the law of conservation of energy that is so important to impress on other students, and perhaps you did a very commendable job in your accounting process at each step.
Of course purely speculation on my part.
The point would be that such a case would not be pure science in that there were more concerns involved than just observation and collecting data. I have been in that same situation myself, and there is very much an experimenter can do during each step to alter the outcome so that the data better fits into the proper range predicted by the calculations. The brighter students learn this quickly, but at the same time they should have been taught the scientific method in its purest form. Most scientists will freely admit that when it comes to controlling variables and collecting data, that they can only work within their limits at the time and do their best. Most real scientists wish they had even more control and better equipment in their quest for truth. The better scientists rarely speak in absolute terms for several reasons. One is due to the limitations of their data collection and control, and another is that they realize that there are still many unknowns and that true science is a continually self-correcting process.
Science is only self-correcting when you can put arrogance and self-assuredness to the side and remain open to experiment and observation, even for sake of merely collecting data, and no matter the source. I know that a big part of the job is verification, repeatability, and proper qualification of methods and sources. I get that, but here's where it gets personal. The attitude that I get from your posts is that of being knowledgeable, but not really scientific. Your active discouragement of pure science (for whatever reason) by brow-beating/bullying, dismissing/discrediting, the use of logical fallacies, and your use of phrases in the same spirit of "what an incredible waste of time" is what I would call a travesty to the pursuit of scientific discovery, or rediscovery.
After reading over your posts and noticing you throwing around terms like: "nobel prize", "best known authority", high dollars amount spent, fact validation due to age or authority, and not the least of which an overwhelming tone of elitism.
At this point it would seem to me that you are a legend in your own mind, and there's nothing wrong with that. It is discouraging to think of you as a teacher and propagating a similar attitude by example.
I am all too familiar with this sort of elitist attitude in academia.
The response or rebuttal is quite predictable in the spirit of:
"facts are facts", and "correcting ignorance with fact is not bullying", etc...
Yes indeed.
In this particular case I have to say that you are far too sure of yourself in some areas. You may be a very competent in some area, but it is absolutely not engine tuning or engine management systems.
Based on what you have posted above, you are talking completely out of your ass once you stepped into the area of electronic engine management.
Legend, authority, or not, I would say without a doubt that I would never ask you to tune an engine of mine, nor could I in good faith recommend you as a tuner, or even to speak competently on the specifics of electronic engine management. Whatever your age, you clearly lack the proper experience in this area, and are apparently loath to admit that.
I can only hope that this characteristic of you has not spilled over into other areas, such as the whole HHO discussion that you have seemingly taken on as a vendetta of sorts. I base that concern on the fact that the majority of your posts in this thread are tied to the "debunking" of the mysterious "HHO promoter" that I have yet to see surface in this thread.
As it stands the only other person in this thread who has presented any credible evidence that they have the combination of a good workable understanding of engine tuning, electronic engine management, and the experience as well has been Robert (E4ODnut) with the Megasquirt systems.
It seems to me that academia could offer more in terms of useful information, support, and encouragement to those who are actually out there doing things. However, it is human nature for elitism in many forms, to be both polarizing and self-perpetuating.
You agree that I'm wrong, and I agree that you're wrong. My guess is that a stalemate will not be good enough for you, and that you will try to bring in more outside unrelated sources for backup, throw in some more logical fallacies, and exert your own style of verbal dominance to the discussion at hand.
This is going to boil down to the fact that I do not trust either your testing methods, or your assessments/conclusions, and you do not trust mine.
Given that, I can think of no better resolution than to encourage more individual experimentation. Why do you seem to be against this?
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03-03-2012, 09:46 PM
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#8 (permalink)
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Master EcoModder
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I apologize if I've missed anything important, Olympiadis, as I glazed over your last 2 posts.
Approximately what does an HHO system cost to install, what are the complications (fuel maps?), and what are the predicted gains? I'll admit I'm extremely skeptical (I've outright dismissed it in the past) but I would be willing to set one up if the cost isn't very much, and do a battery of tests.
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03-03-2012, 10:23 PM
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#9 (permalink)
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oldschool
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Quote:
Originally Posted by Ecky
I apologize if I've missed anything important, Olympiadis, as I glazed over your last 2 posts.
Approximately what does an HHO system cost to install, what are the complications (fuel maps?), and what are the predicted gains? I'll admit I'm extremely skeptical (I've outright dismissed it in the past) but I would be willing to set one up if the cost isn't very much, and do a battery of tests.
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I'm sorry but I have nothing to do with HHO sales or promotion of any kind.
You are correct in being skeptical of any claims from both sides of the isle.
From what I gather, many people have attempted to use HHO to improve fuel economy and ultimately failed. That fact seems perfectly believable to me because many who attempt the more common style of tuning with just air and gasoline also fail to get the results that they seek.
I certainly wouldn't let other's failures stop you from testing something you are curious about no matter what it is.
I have to admit that at this point my curiosity is also raised to the point of seriously considering doing some testing myself. If for nothing else to determine if HHO is in fact useless as an oxidizer which has been claimed here in Mr. Frey's post.
There are also many claims that HHO applied correctly has resulted in significant increases in fuel economy. These reports may be in error, but that should be determined by investigation and not theory. The investigation into why some people get results at all could be useful in revealing information that was not considered before.
I am sorry to say that as of yet I have not tested HHO in any way, but that could change this year as a project will be coming up that would lend itself well as a proper test-bed for such a thing. If things go well I may have have useful data to report by the years end. The vehicle is a shell at this point, which explains the long time period required.
As with any testing I'm sure I'll find it quite interesting no matter what the final results may be.
My bringing up the term "HHO" in this discussion was only to point out glaring errors I have observed from both sides of the HHO discussion concerning the dynamics of engine tuning, and how that is relevant to the use of BSFC maps. I did not mean to mislead you.
It seems a bit sad that when a term like "HHO" is used here on this forum the prevailing attitude is automatically so negative. Someone along the line must have been scammed by one of those late night infomercials promising to run your car on water. We all hate scams, but it's no excuse to lose your reasoning ability. It is however a very human quality, similar to what gave rise to witch trials.
edit: If anyone has any question like this for me please pm or email me so I can stay out of this thread. Thank you.
Last edited by Olympiadis; 03-03-2012 at 10:43 PM..
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03-03-2012, 11:21 PM
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#10 (permalink)
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Master EcoModder
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I gave up on the idea of HHO being a practical solution when I did some research and found out that one liter had the energy content of 1 and 1/2 wooden matches.
I don't think an olive branch which includes a demand for apologies from others who have their own personal experiences and unique fields of knowledge, is really an olive branch. A gift with strings attached is not really a gift.
While I think there may be some benefit to using modern computer systems to micro manage engine operational parameters, when you use open loop as the core of your strategy, I get concerned about the elimination of closed loop and the emission requirements and legal ramifications of such elimination. Potential fines and possible Felony charges.
Personally I think the throttle restriction should be eliminated altogether, along with any control which results in anything but best BSFC operation. I guess that is because my preferred design would eliminate any direct connection between the engine and drive wheels altogether. It could be a direct connection, but only when the load demands on the vehicle were coincidentally at the precise point where best BSFC was where the engine could handle the load, and your capacitive storage was depleted.
Trying to find a more efficient way to make an engine more efficient seems to me (and me only) to be an exercise in futility, kind of like a band aid on a cancer, when the best solution is to cure the cancer, by eliminating anything but full atmospheric pressure as the pressure available to the cylinder (unless you supercharge either mechanically or with exhaust gasses) any time the motor is running. If the system does not need that much power, then capacitive storage of previously created energy reserves would continue to propel the vehicle, until the engine would be restarted to replenish the capacitive storage. On at best BSFC or off, all or nothing.
Internal P&G without using the vehicle for the storage (P&G), which requires constant fluctuation in speed, compared to internal capacitive storage (accumulator or capacitor), which eliminates the fluctuation in speed.
Any incremental increase in efficiency that could be added to the existing peak of any engine you choose for power, would only increase the overall MPG of the vehicle above and beyond it's present state. It would also be much easier to accomplish when you were only facing a very narrow range of fairly high load and RPM. Even the pistons and connecting rods could be redesigned as well as virtually every other component of the engine itself.
Ultimately you would have a much better chance to actually achieve homogeneous charge compression ignition of gasoline and very possibly the total elimination of any after treatment of exhaust gas altogether.
While I (just me) am convinced we will see that pathway eventually achieved, it does seem like there are few who really understand the potential, including many who have a much higher level of formal education than myself.
You see gentlemen, I can buy or borrow the knowledge of almost anyone who has spend decades in an education environment, show them my ideas, and get confirmation of my beliefs. That's a much better solution to me at age 61, than going to any major technical university for a few years to get to the level some seem is necessary to be relevant.
I spent $4000 to do just that at Virginia Tech. I got 8 students and a MIT Doctor of Engineering to look at my design. After a year they told me what I already knew. It would work, and it would work as well or better than anything existent in 2010. Nothing better has appeared since 2010, and not many people even try to understand the principle.
Oh yes the same design will work equally well with a battery and electric motor as the energy provider for capacitive storage, without any current modulation necessary, just an on-off switch controlled by pressure levels in the accumulator or current levels in the capacitor. Everything exists today and does not depend on any future developments. When future developments become reality the system will just become that much more efficient, but right now the potential for 80-100% improvement in mileage in every motor vehicle on the planet.
Exists TODAY.
regards
Mech
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