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Alternative fuel

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Ok, here's the run down on engine efficiency:
(Please note, I've found that sources are not all on the same page, but most agree to the following)

Stock IC engines - roughly 20%
typical low compression engine - 26%
highly modified racing engine - 34%

So I would say most people drive stock IC engines, I do.
So here's how you can see it, you feel really hungry today, so you go and buy a nice texan-steak at the local butcher, you end up paying R150 for it.
So when you get home, you cut off 4/5 of your steak and chuck it in the dust bin, :eek:, I know. You really enjoy the 1/5 of the steak, but somehow still feel hungry.
So what did you really pay for your steak that you have enjoyed?
What should you have paid for the steak that you have enjoyed?

It may seem elemental, but what is my point?
 
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I think we can agree that low compresson engines provide less efficiency then a high compression engine.

Most stock engines are low compression to control polution. I am not sure why you list different figures for stock and low compression. But it does not matter.

There are two things I know of that can increase engine efficiency. The first as mentioned earlier is to raise compression. The second is to reduce all forms of frictional losses withing the engine.

We can raise compression. I think water injection could be used to keep the burn temperature at that of a low compression engine and that keeps polution down. Because our engine needs to last more then a few 100 miles it will be a bit heavier the a race engine with similar compression.

Drag comes in two forms, mechanical and air flow. The mechanical can be addressed with roller bearing where possible. Roller timing chains, roller cams, roller rockers, maybe even roller rod and main bearings.

Breathing is all about good flowing heads and mainfolds. Think of it as ported and polished from the factory.

If you look at a factory sand cast head the finish is a very rough with ample ridges and bumps from the casing process. There is a lot of room for improvement. Casting could be (and maybe is) improved over this.

The factorys could build race efficient engine or better. It would cost more to make it happen but over the life of the care it would pay back many times.
 
The factorys could build race efficient engine or better. It would cost more to make it happen but over the life of the care it would pay back many times.
Perhaps the Govt, should help with the cost of making such improvements, ie. fund company research, or perhaps rebates to the consumer or some such incentive. I agree there are many things that could be done, but how do we get it done, that is the question?
 
Little (more like none) research is needed to build such an engine. The roller parts have been sold by 3rd party people for years. These days you can build a flow bench from a kit using motors from old vacumn cleaners. Maybe some work to get a better casting system in place. They exist but maybe not on a large scale.

A lot can be done with what we already know how to do. But car makers need motivation.

To some degree this may already be happening. Some of the intake setups I have seen in newer cars look better then the classic systems. But I have no idea how much time the maker put into it. I am failry sure the high end engines are better designed then they used to be. But the run of the mill engine that most of us buy needs a lot of work.

Perhaps the Govt, should help with the cost of making such improvements, ie. fund company research, or perhaps rebates to the consumer or some such incentive. I agree there are many things that could be done, but how do we get it done, that is the question?
 
What I mean is that all these improvement will cost a great deal to tool up for. Someone has to incurr the initial cost for such a thing. If the car makers do it, then the cost will go to the consumer, and no one could afford it. That is why I suggest some sort of incentive program.
 
What I mean is that all these improvement will cost a great deal to tool up for. Someone has to incurr the initial cost for such a thing. If the car makers do it, then the cost will go to the consumer, and no one could afford it. That is why I suggest some sort of incentive program.
Yes and no. Much of it like roller chains, rockers, and cams can be purchased just as automakers purchase the parts they are using now. The better parts will only be marginally more expensive when purchased in bulk.

The average consumer is buying a car with thousands of dollars of crap they may or may not want but surely do not need. I think most people would give up the electric remote mirrors, electric windows they never open, and heated seats for another 10 or 15 MPG.

In production the cost should be under $500 per engine. For sure less the $1000.
 
I was also concerned about the low compression figures, but it dawned on me that forced induction engine run a lower compression ratio figures, although that seems to change. The new A$ 1.8T FSI runs 9.1:1, that is roughly what normal engines run, maybe slightly down on NA engines
I presumed these stats were based on that, I should have mentioned.
Something like the latest Porche engines run around 12 or 13 to 1. Wonder how they get past knock.
I think why main bearings, etc. are still conventional type is due to possible reliability issues with roller bearings. Could be wrong, but that makes sense.
I've seen roller bearings pack up far before others in truck use.
Is it also not true that the thin layer of oil between the bearing seat and bearing will lower friction?
Also a lot of research have gone into input air flow, and heads are designed to cause air to enter the cylinder with as much turbulence as possible, so I'm sure manufacturers spending top dollar on such would also keep things smooth.
The major stated reason for inefficiency is heat loss in IC engines, but I'm sure the "this forces that forces that forces that" syndrome also must have a huge effect.
It seems BMW have almost exclusively walked away with the 2008 engine of the year awards, I compared their 2.0 to my now 8 years plus old mondeo engine. They do not have much on my "old" mondeo, not power output, not acceleration, not top speed, sure as hell not fuel consumption, 9.4l/100km (them) vs. 7.7l/100km (mondeo) worst case.
So where have we gone in the last ten years, if that's how things stand with one of the supposedly top brands in the world taking awards left right and centre.
IC is dead, long live....... my bicycle.:)
 
Briliant

3v0 I'm seeing the way your thinking now. So, with a cylinder using Hydrogen which I understand is producing 3,000 degrees or so. If you are to port that into another sub carrier which is utilizing water into steam you get both combustion and stroke then port to another system using steam ? No, radiator.

Am I close ? with all the extras taken out as weight and providing space for added equipment needed for the steam portion of the work horse.


Correct me please. kv:)
 
It seems BMW have almost exclusively walked away with the 2008 engine of the year awards, I compared their 2.0 to my now 8 years plus old mondeo engine. They do not have much on my "old" mondeo, not power output, not acceleration, not top speed, sure as hell not fuel consumption, 9.4l/100km (them) vs. 7.7l/100km (mondeo) worst case.

Have you ever driven a BMW?, generally they far out perform Mondeo's.

I had occasion to borrow a 1 series BMW the other week, it was a manual gearbox 1.8L diesel - it absolutely flew, didn't seem like a diesel at all (and probably better than most 1.8L petrol engines as well). Supposedly they claim 65 mpg from it as, certainly from how it goes the time of the diesel engine has arrived. I suppose it's no coincidence that Audi diesels have won the Le Mans 24 hour race the last few years?.

Our vans at work are 1.9L Citroen diesels, so should go better been a bigger engine? - fairly obviously, not by a LONG, LONG, way.

In my short use of the BMW, I did bang my head every time I got in it though :D and it had far too many controls to play with, I struggled winding the windows down, and by the time I'd managed to find out how, it was getting cold (posh car, air con as well!).
 
Okay, ok, you've asked for it.

Road test done on both cars by same local magazine. their standard is super high.

BMW 320i steptronic
R301000
115kW@6700rpm
200N.m@4250
6 gears rear drive
0-100km/h 9.5sec
max 215km/h
fuel 9.4

Ford Mondeo 2.0i Ghia (I have the trend, bit lighter)
R220 000 (way back)
107kW@6000rpm
190N.m@4500rpm
5 gears front drive
0-100km/h 9.3sec
max 215km/h
fuel 7.4

Interesting reading.

For interest sake:

Jaguar X-type 2.0 SE
R303000
115kW@6800rpm
196N.m@4100rpm
5 gears rear drive
0-100km/h 12.69sec
max 198km/h
fuel 10.72

Fuel consumption is l/100km.
That should back my previous claims. Tests done a sea level, Cape Town if you know the place. There may be slight variation in ambient temperature and wind speeds, but should not make that big a difference.
 
I think why main bearings, etc. are still conventional type is due to possible reliability issues with roller bearings. Could be wrong, but that makes sense.
I've seen roller bearings pack up far before others in truck use.
That is why I said maybe on the main and con bearings.​

Is it also not true that the thin layer of oil between the bearing seat and bearing will lower friction?
Also a lot of research have gone into input air flow, and heads are designed to cause air to enter the cylinder with as much turbulence as possible.
Engines are air pumps, smooth air flow is essential to economy. An engine with a carb does better with turblent airflow in that it helps vaporize the fuel. This is less of an issue with port inject and not an issue with direct injection. You always want the exhaust to be as clean flowing as possible. In short the short commings of the fuel system requires bad intake design. Fix the fuel system instead of busting the intake.

It seems BMW have almost exclusively walked away with the 2008 engine of the year awards, I compared their 2.0 to my now 8 years plus old mondeo engine. They do not have much on my "old" mondeo, not power output, not acceleration, not top speed, sure as hell not fuel consumption, 9.4l/100km (them) vs. 7.7l/100km (mondeo) worst case.
So where have we gone in the last ten years, if that's how things stand with one of the supposedly top brands in the world taking awards left right and centre.

It does make you wonder about what criteria they used to judge the engines.

IC is dead, long live....... my bicycle.:)
I bike too. There are a few of us in the over 50 crowd in town that do. Very few in the 20-40 range. I just got a bike with a set of elliptical crank gears. I like them a lot. I ride to school when the weather permits and I do not have too much to carry. For me it is more about health then the gas. My BP hit a record low (for me) last fall.
 
eliptical crank gears?

I've enjoyed off-road more, especially the high speed stuff.
It's really a good feeling to sit in the bath and pluck small stones from under your skin with a tweezer.

Only have a Giant Rincon SE, but I haven't done too much cycling these days, driving on SA roads with a cycle on your own is like putting a gun to your head.

We are now officially one of the worst countries regarding road deaths.
There was a time when cyclists were knocked down about as frequent as we have power interruptions.
Now it seems to be the motorbikes' turn, they are being knocked down about daily. (Radio traffic reports)
Really bad
 
If I remember right it's the gasoline direct injection engines that likes it real rough around intake. More and more manufacturers are conforming to this standard. Ports have spiral like shapes to cause turbulence inside the combustion chamber, the piston heads are also weird design, with funny ramp up set-up to mix things further.
Real interesting.
 
The power of steam.

Alright in the example I have above. If you are producing 3000 c and then take super heated gases out to another cylinder with steam add a pinch hydrogen the expansion will be above what you would need in the first stage ? It would be more steam engine than combustion.

If this single cylinder is just the first stage stroke heat producer the following are the crank portion with equal power distribution.

I don't see anything like this for automotive but maybe a power plant for electricity.

kv

Edit: I think it would be more like a bomb because spontaneous combustion of hydrogen about 585c
 
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Is that 3000 deg.C? Wow, how would you get it there?
What would oxygen be like at that?

I think it refers to the adiabatic flame temperature of a hydrogen-oxygen torch, which is 3079 °C according to Wikipedia. Same source, oxy-acetylene is 3100 and MAPP-oxygen is 2927.

John
 
eliptical crank gears?
The gears are not round. They have a longer lever arm when you leg is in front of the crank axle and shorter when you are at the top or bottom of the crank. It evens out the power you apply. No more vom vom.

If I remember right it's the gasoline direct injection engines that likes it real rough around intake. More and more manufacturers are conforming to this standard. Ports have spiral like shapes to cause turbulence inside the combustion chamber, the piston heads are also weird design, with funny ramp up set-up to mix things further.
Real interesting.

There is a difference between 'turbulance' designed into an engine to aid combustion, and that power loses caused by rough/bad (runner, flash, etc) casting. A rough intake would hinder a direct injection engine, use more power to fill the cylinder. But well designed shapes to cause the air to swirl is another thing.
 
I think it refers to the adiabatic flame temperature of a hydrogen-oxygen torch, which is 3079 °C according to Wikipedia. Same source, oxy-acetylene is 3100 and MAPP-oxygen is 2927.

John

So then under pressure it reduces dramatically. I guess.

kv
 
I am not saying that what you are thinking will not work.

The crower cycle injects water into the combustion cylinder at the top of the exhaust stroke to get an additional power stroke. You do not get to use the heat lost out the tail pipe but you do recover what you would have lost out the radiator.

Steam engine were often two stage. The exhaust from one cylinder drove the next one. There is a lot of heat going out the tail pipe. Some way of recovering that would be good too.


3v0 I'm seeing the way your thinking now. So, with a cylinder using Hydrogen which I understand is producing 3,000 degrees or so. If you are to port that into another sub carrier which is utilizing water into steam you get both combustion and stroke then port to another system using steam ? No, radiator.

Am I close ? with all the extras taken out as weight and providing space for added equipment needed for the steam portion of the work horse.

Correct me please. kv:)
 
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