I am not an engineer this is what I know please ask an expert and the net for true details but i will give it a try.

In a normal engine during the compression stroke, as the charge of air and fuel is being compressed by the pistons movement up to wards top dead center, 5 to 15 degrees BEFORE piston reaches TDC the spark plug ignites the mixture , WHY ?

This action of pree ignition in intended to allow for a complete flame deflagration or complete combustion of gases,
Hence complete pressure build up before Piston is at TDC, this timing effort is intended to make best use of the gasses pressure, see you want to have the maximum and complete gas pressure al ready built up meet the piston at TDC or Just after TDC, so that gas pressure is at maximum and burning of gasses is already complete , other wise if you ignite the charge AT TDC then you will have flame deflagration following the piston down hill trying to catch up to it and pressure is in the process of building up or being generated as the piston is going down , in other words pressure is trying to catch up to the downward speeding piston , instead of acting on the piston with pressure.
I hope that is clear .

it takes a bit of imagination to imagine that but it is true you can test it on old cars with classical ignition systems.

Timing of the ignition depends of many thing , fuel type , load, air , RPM , engine design etc

That is why computer engine are more efficient and powerful you can perfectly time the ignition.

In the Wankel one of there two processes can take place but not the other

The same charge compression does take place in a Wankel, but not the pree ignition

In the Wankel the pree ignition is imposable to implement for lots of reasons, starting from the fact that the area of the rotor is large enough that the pressure of the pree ignited gases would prevent the rotor from completing its turn.
Also the combustion chamber of the Wankel is very small ,and is momentarily created it doesn’t last that long .
this creates more problems one of which is the fact that the flam deflagration is so slow to spread across all of the gas fuel mixture (charge) so they use two spark plugs to ensure as wide spread flam deflagration as possible.

So you cannot have gases pressure build up as the rotor is moving to TDC . you can only hope for best ignition exactly at TDC and since the rotor passes to fast at TDC the need to create as many as possible of ignition points to deflagrate the flam as much as possible.
If I know correctly Wankel don’t do good n low RPMs they have to Rev up to get any power .

By the way Wankel is rubbish, it is not even a rotary engine it is an eccentric rotary engine.

See my blog or email me if you want to know the true rotary engines that have the true power of rotary engine and none of the Wankel disadvantages .

Pree ignition is possible in my engine design,complete torque, no wobbly mass, very high compression ratio , all ready supercharged, higher volumetric efficiency , high power to weight ration etc .

I hope this answers your question.

sorry for the long post

But I think you got the wrong idea.

I am not promoting the Wankel engine.

The Wankel engine is an Ec-centric Engine, with only 20 to 30% thermal efficiency.

What I am promoting is Concentric Circular engines, that achieve 60-70-90% even 95% thermal efficiency.

Mr.Vladimir Prelovac Thank you for having my words on your blog. I want to add you to my web log but I didn’t know where.

Please all visit my web log for more details especially

http://dreamer3000.wordpress.com/circular-engine/

in my weg pages and blog roll you will fined
Hekal has the best literature.
Ciqular has animation and Pictures of the model.
VGT has animations of explanations science .
Jonova has nice photos and links to University of Arizona.

Issa Omran
Best regards

please visit the real discussion about circular engines

http://dreamer3000.wordpress.com/circular-engine/

I wanted to link to your weblog bit didn’t know where to put yours.

Please Visit the main page

Best regards

Wankel engien is fake Circular engine there is a fmily of engies

Called the circulare engines
here are the Advantiges details
a- The small size of the combustion chamber in Circular engines means higher pressure, while jet engines combustion chamber are huge.

b- Simplicity , un like the jet engine that requires really high end technology, high-Tech manufacturing and sophisticated designing aerodynamics calculations and engineers to manufacture / maintain. This circular engine requires basic machining abilities and basic understanding of rudimentary science not just to maintain but also to Home produce so manufacturing infrastructure is cheaper and smaller.

c- More / Tighter Sealed, meaning better utilization of gas pressure, that would explain the increase in thermal efficiency.

d- Thermal efficiency it is Calculated by a Professor Hekal to be any where from 60% to 90%. While any Jet engine is 50% thermal efficiency. Number don’t lie check Hekal website from my blog.

e- Which would mean less fuel consumption . also since it is a pulsating engine. burn small amounts of fuel sequentially not continually like Jet engine, so this Circular engine uses less fuel even at higher RPMs.

f- The increase in Thermal efficiency would also mean it would run cooler that makes sense if it has higher thermal efficiency it means it is making more use of the thermal / heat power so it is cooler running.

g- Which means even cheaper metals can be used. Unlike Jet engines that require really expensive metals and high end sophisticated metals casting / forming techniques. Or like the normal ICE that wastes a lot of heat putting limitations of the manufacturing of the parts of the engine like the head and valves and piston .So the already established metallurgy science wouldn’t find it hard to deal with a cooler running engine. It might use normal Alloys if not Aluminum. Which also means Cheaper to produce.

h- Looking at previous point Can be manufactured any where even HOME MADE if you will, DIY. So its Easier to manufacture.

i- Smaller in size even than a Jet engine .check the MYT engine comparison Picture. Smaller cars vehicles

j- Lighter. I estimate 50 to 60 KGs I believe 20KGs is possible for an engine that is more powerful than a V8.

k- Produces less sounds than a Jet engine. I think that is a BIG BIG advantage.

l- Higher Compression Ration 30 to 1. I don’t think even Jet engine produce such high compression ratio, this means this engine would be more powerful than any engine all ready manufactured. And it means especially that hydrogen is a wonderful fuel for this engine bringing the hydrogen economy to existence also for smaller WFC system. Since the energy density of Hydrogen is not good enough with these Circualr engines it would make sense.

m- Easy to maintain.

I think producing this Circular engine in your own work shop is a lot more attainable than a home made Jet engine don’t you think??

The Hekal has the Bet scientific literature

The Cirqular has nice clear Pictures of the prototype model and a movie clip very important people on the board of the company.

The VGT is not so friendly but has nice animations along with scientific explanations of the pros of the engines, but there specific design is not so good.

The SS-BF engine page has nice Films of actual model(s), but these engines waste energy but there stop and start motion. At least three different models from three different countries.

The page Circular engine has my attempt to explain the key differences.

The right side shows my summary of original websites while the lower right side of the pages show the original website links

The normal Reciprocating piston engine has negative torque which consists of work against air fuel mixture in next charge preparing cylinder/ Piston + work against the Springs cams frictional forces + the increase of the Gases started burning Before TDC of the next piston.

By making combustion chamber in circular engines separate from the Induction /compression chamber you don’t get the negative torque of the pre detonation of the Charger before TDC. Which means that wastes negative torque is moved to the positive side in circular engines meaning you win it back.

Also meaning no knocking.

There is no advancing of spark in Jet engines since they are continuous burn engines.

The Wankel doesn’t have any advancing of the spark, losing huge amounts of power since the gasses are actually following the rotor. And is only efficient at high RPMs.

Diesel

If you didn’t know I tell you that Diesel has more power (enthalpy) than Gas

But Diesel engines have huge amount of negative torque and no advancing of detonation, while in any of these circular engines Diesel would have NO or very small negative torque and would have advancing or detonation, so the diesel would end up more powerful than Gas engine

I hope this answers all questions relating to the advantages

I will not evade the fact that there is no one single working design. there are huge problems with sealing . and combustion chamber forming.

The problem is in designing one that really works. That is where the race is.

Beset regards

http://dreamer3000.wordpress.com/circular-engine/

It was amazing, as it used a small 2-stroke engine to pump air into a "compressed air" tank.

The compressed air was then used to drive the main engine cylinders.

Apparently, it was incredibly fuel efficient... and could also generate a lot of power (for short amounts of time).

I vaguely remember figures like 5 liters per 100Km, and 0 - 100Kph in 7 seconds... really impressive.

What happened?

Apparently a big car maker bought the technology, and then shelved it.