Improving The Efficiency Of Combustion Engines.

[taurus26]

Some years ago I developed a theory relating to measuring the efficiency of balanced systems or nearly balanced systems (according to the laws of physics ).
It was not until later, I realized that the combustion engine of a motor car was in itself a balanced system. Or rather the individual pistons within cylinders were systems within the overall system of the engine! (They could be considered individual motors making up a part of the total motor)
Anyway getting back to the theory - This required the monitoring of the system over a time frame of five timing points and at the end of that time to come to a logical conclusion as to whether the system was operating as efficiently as it could be or if there should be a small adjustment made!
This theory could then be applied to each cylinder of a combustion engine. There would be one timing point at top dead centre, a second at the bottom of the downstroke and three others in between.
The monitoring of the system would be via the compression ratio at each timing point per cylinder. Those five readings could be linked to get an overall picture of the performance of each cylinder.
ie.
1 - 2
1 - 3
1 - 4
1 - 5
2 - 3
2 - 4
2 - 5
3 - 4
3 - 5
4 - 5
These figures can be fed into a computer for analysis of exactly how much fuel that particular cylinder required injecting.
I am convinced this theory would work and would result in -

1. Greater fuel economy.

2. Greater horsepower for size of motor.

3. Greater Torque.

4. Smoother throttle for all loads.

5. Less maintenance costs.

6. Less emissions.

7. Cooler running.

I also am convinced that much of the present gadgetry on modern engines would not be required and would remain obsolete. With the cost of fuel rising exponentially the further we get into this Century, I believe it is imperative that we run smaller cars with more efficient engines.

In creating this post I wish it to be known that I am a layperson with very limited access to working on motor engines. All of my theories have been derived from logic! Excuse the pretty rough explanation involved!

With Kind Regards,

taurus26

[The General]

So that I might understand a little more. You say that each cylinder is a system in its own. This is because each one goes through all 4 strokes and is not dependent on the others. I'm a correct?

If your theory is correct, do you have a theory as to why car manufacturers have not applied this?

[taurus26]

Thank you very much for your reply The General!

1. Exactly. The piston cranks are linked mechanically, but only to provide additional Horsepower for each cylinder. Each operates independently of each other and as such should be fueled independently. I consider that current methods of fuel distribution are crude. I understand there is considerable improvement in the Pumpe Duse Engine but I haven't checked that out fully yet!

2. I don't know! Perhaps because it was relatively easy to consider the engine as "one" if reasonable performance could be achieved when fuel costs were relatively cheap. (Not that 28% efficiency is reasonable in this day and age.) Plus it may have seemed that to fuel each cylinder seperately would be too expensive, while I believe that doesn't have to be the case at all!

If I may at a later stage, I will continue with information left at an Aussie site. It was considered feasible that compression chamber pressure sensors could be added.

[amorak]

uhhh... Ever since the invention of direct fuel injection each cylinder has been supplied with its own regulated amount of fuel... Each cyinder has a fuel injector right at teh base of the intake runner.

The latest take on this is Direct Fuel Injection, where super-high pressure, electronically controlled fuel injectors are used to inject fuel directly into the combustion chamber at something like 10,000PSI. TRhis allows for a 30-40% higher compression ratio then with traditional fuel injection.

However, this has resulted in only 5-10% better fuel economy. They have used individual wideband O2 sensors on each cylinder bank and made sure each chamber was running as stoich as possible, so I don't see how your theory could be of use?

[taurus26]

As I indicated on my first post, my knowledge of the technicalities is limited.

What I do have is copyright, which can be related to a computer program. A part of my documentation reads -

It is claimed that by the systematic observation of a balanced or a nearly balanced system, it is possible at the instant after that observation to either more accurately measure the system or to improve the performance of the system.
In general, the logic applied in the new method of system analysis is such that by systematically eliminating or acting on high negative elements within a system, it can be shown that accuracy or efficiency of the system may be logically improved automatically.

So there you have it, my claims probably relate to the programming of the ECU as much as anything.

The fact that compression was directly related to so many of the variables within a cylinder, means that it is the ideal component to be monitored. Regarding the pressure sensor, reliability would be the main requirement. It would have to only maintain a reasonable degree of accuracy.

I think the main thing to understand is that by linking the ratios, you are establishing a very balanced component. I truely believe that to be set up in this way the engine would be purring like a kitten!

Other items presently controlled by other means could be continued as a safeguard if necessary.

[The General]

Originally Posted by amorak

Ever since the invention of direct fuel injection each cylinder has been supplied with its own regulated amount of fuel... Each cyinder has a fuel injector right at teh base of the intake runner.

My 1989 Mazda had multi-port fuel injection i.e., 1 injector per cylinder. What it did was deliver the fuel into the intake runner of the cylinder however, if I'm not mistaken, the fuel rail was alway pressurized and injected fuel into the runner of the cylinder that is not on an intake stroke. Basically wasting fuel and polluting.

Was Honda's PGM FI any different? Am I completly off my rocker?

I'm guessing that the PD system has individual pumps on each injector.

[amorak]

What you're descriping, General, is batch fire injection, where the inejctors fire in batches. This is a waste of fuel because it injects fuel when some cylinders are not on the intake stroke. However, every typical FI'd car for the past 10+ years has used sequential injection (or a variant there-of). This, as its name suggests, insured that fuel was only injected into the cylinder runner of a cylinder on the intake phase.

DFI, or Direct Fuel Injection, is one step better like I mentioned. Not only is it sequential fuel injection, injecting fuel only on combustion/intake strokes (depending on the type of DFI you're using) strokes, But it is done at a very high A/F ratio, typically 14 or 15:1 (regualr cars are ~11:1). This allows for more power and ~10-20% less fuel used.

The idea of each cylinder being it
s own system has been in use since the days of carbuartors... You check each plug to ensure each cylinder is getting the appropriate amount of fuel. This is crude of course, but that's how ti was done. Sequential FI took it one step further, with engineers using O2 sensors on each cylinder exhaust runner to dynamically measure A/F ratios. With computer controlled direct Injection and widebnad O2 sensors, we're even further along then before!

The problem does not lie with metering the air and fuel together at higher and higher rates, as it does not create 1:1 gains. Increasing teh A/F from 11:1 to 15:1 is a 27% increase in the A/F ratio, yet it correspnds to ~10-15% better fuel economy.

The trouble lies with gas itself... In teh best funcitoning motors we can only extract 1/4 of the potential engery in gasoline. We need a better fuel, not better metering/application of fuel....

[taurus26]

Your knowledge is very good amorak!

I think we have been able to gradually develop things in a positive way!
Whether it ultimately proves to be worthwhile remains to be seen.

I would like to offer you an invitation to call over to Aussie at www.AussieCarForum.com to see how we're going.

Your input would be welcome!

Regards,

taurus26