Check this ... different.. Internal Combustion Engine out...

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GasX

Lifer
Feb 8, 2001
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This is a horrible design. Instead of using the cumbustion energy to add energy to an already moving system, the combustion energy is going to be mostly wasted bringing the piston thingy to a stop and reversing it's direction.

It is inefficient end of story

(Am I wrong here?)
 

SagaLore

Elite Member
Dec 18, 2001
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Originally posted by: Zenmervolt
That's an awful lot of force that will be slamming the mainshaft back and forth. That's the main problem that I see, the mainshaft is going to be slammed into spinning into an opposite direction with regulatiry, how is it going to hold up?

Also, this theory is an internal combustion engine. It's not a reciprocating engine, but it is an internal combustion engine.

ZV

The current design is flawed... but with some reconfiguration, it could be made safer and more efficient. The two chambers need to be facing each other and not side by side. Then instead of a long rod with the swivel in a straight line, it would be a short rod with the swivel in a symetrical placement. This will help balance the inertia, and then at any given time one chamber will be firing keeping the swivel from hitting full force into the wall. Problem still exists when engine is getting shut off.. counter-force stops, allowing swivel to hit...

Problem can yet still be solved by slowing down the engine, and making this a slow working Diesel. The design does allow for some huge compression ratios given the right chamber dimensions. In fact this would make a diesel even more efficeint given the direct force compression on the parallel chamber. The swivel would never hit the wall, unless, a valve were to not seal right, then you'd end up with a huge BANG.
 
Jun 18, 2000
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Originally posted by: geno
I think the torque of the main shaft is something that can be coped with.
You are absouletly correct! I have no doubt that the main shaft wouldn't shatter immediately. The issue at hand is, what happens after 2 or 3 years and 40,000 miles? The recriprocating force of the main shaft on the "stop block" will lower engine life.
Originally posted by: Zenmervolt
Seems to me that after the exaust stroke there is nothing to drive the flap back.
Remember there are 2 banks of flaps. When one bank is in its exhaust cycle, the other bank could be in the combustion cycle. As long as the cycles are opposite each other, the exhaust stroke shouldn't be an issue.
Originally posted by: SagaLore
I love new engine technologies, especially the wankel
The wankel rotary isn't exactly new technology. The rotary engine has been around for some 50 years.
 

notfred

Lifer
Feb 12, 2001
38,241
4
0
Originally posted by: Mwilding
This is a horrible design. Instead of using the cumbustion energy to add energy to an already moving system, the combustion energy is going to be mostly wasted bringing the piston thingy to a stop and reversing it's direction.

It is inefficient end of story

(Am I wrong here?)

That's how a traditional reciprocating piston engine works.
 

GasX

Lifer
Feb 8, 2001
29,033
6
81
Originally posted by: notfred
Originally posted by: Mwilding
This is a horrible design. Instead of using the cumbustion energy to add energy to an already moving system, the combustion energy is going to be mostly wasted bringing the piston thingy to a stop and reversing it's direction.

It is inefficient end of story

(Am I wrong here?)

That's how a traditional reciprocating piston engine works.
not exactly, the crank shaft is an ever rotating mass. If you skip a spark, the piston still goes down. With this engine, wouldn't it slam into the wall?

<= not particulary mechanically inclined...
 
Jun 18, 2000
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Originally posted by: SagaLore
The swivel would never hit the wall, unless, a valve were to not seal right, then you'd end up with a huge BANG.
Good point. As long as air or exhaust is in the chamber, and the valves were sealed properly, it'd be impossible for the flaps to slam into the head. But you're going to lose efficiency since some of the energy from the power stroke negated by the force of the compressed air opposite the flap.
 

SagaLore

Elite Member
Dec 18, 2001
24,036
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Originally posted by: Cyberian
Originally posted by: Nemesis77
Let me get this straight.... The guy can't make even a simple webpage, yet he claims to be able to build a revolutionary engine?
I bet my heart surgeon can't make a webpage at all.
I don't think one thing has anything to do with the other.

Your heart surgeon can't make a web page! :Q That's horrible. :(
 

SagaLore

Elite Member
Dec 18, 2001
24,036
21
81
Originally posted by: Mwilding
This is a horrible design. Instead of using the cumbustion energy to add energy to an already moving system, the combustion energy is going to be mostly wasted bringing the piston thingy to a stop and reversing it's direction.

It is inefficient end of story

(Am I wrong here?)

Hate to break it to you, but that's how the piston engine works as well.

but you are correct. that's why the search for a perfect rotary solution is the key to best efficiency
 

SagaLore

Elite Member
Dec 18, 2001
24,036
21
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Originally posted by: KnightBreed
Originally posted by: geno
I think the torque of the main shaft is something that can be coped with.
You are absouletly correct! I have no doubt that the main shaft wouldn't shatter immediately. The issue at hand is, what happens after 2 or 3 years and 40,000 miles? The recriprocating force of the main shaft on the "stop block" will lower engine life.
Originally posted by: Zenmervolt
Seems to me that after the exaust stroke there is nothing to drive the flap back.
Remember there are 2 banks of flaps. When one bank is in its exhaust cycle, the other bank could be in the combustion cycle. As long as the cycles are opposite each other, the exhaust stroke shouldn't be an issue.
Originally posted by: SagaLore
I love new engine technologies, especially the wankel
The wankel rotary isn't exactly new technology. The rotary engine has been around for some 50 years.

Well... no it isn't new. But it's still a fresh idea. The amount of time and effort put into the steam engine, then the otto-cycle internal combusion engine, it wasn't fair for the wankel to fail so fast. One of the arguments against the DKM wankel is that it actually consumed more fuel... but, a lot of the exhaust was unburnt fuel. So then to cope they ran the exhaust through a high-temp burner, which needed more fuel, to finish the burning. So you ended up with super clean exhaust and a lot of spent fuel. If they'd just improve the fuel/air ratio and work more on efficient thermal combustion inside the chamber, I think wankel would be #1 in fuel economy.

Years ago I came up with some pretty nice designs on improving the seals and fuel injection. If only I had a few engineers, and some funding...
 
Jun 18, 2000
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Originally posted by: SagaLore
Hate to break it to you, but that's how the piston engine works as well.

but you are correct. that's why the search for a perfect rotary solution is the key to best efficiency
There is no such thing as a "perfect rotary solution." The small combustion chambers and shape of the rotor makes it extremely difficult to get high torque numbers out of a naturally aspirated rotary engine.

The perfect internal combustion engine has not been invented. There will be significant advantages and disadvantages with any solution, though there's a reason the 4-cycle piston engine has become the mainstay of the auto industry.
 
Jun 18, 2000
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Originally posted by: SagaLore
Well... no it isn't new. But it's still a fresh idea. The amount of time and effort put into the steam engine, then the otto-cycle internal combusion engine, it wasn't fair for the wankel to fail so fast. One of the arguments against the DKM wankel is that it actually consumed more fuel... but, a lot of the exhaust was unburnt fuel. So then to cope they ran the exhaust through a high-temp burner, which needed more fuel, to finish the burning. So you ended up with super clean exhaust and a lot of spent fuel. If they'd just improve the fuel/air ratio and work more on efficient thermal combustion inside the chamber, I think wankel would be #1 in fuel economy.

Years ago I came up with some pretty nice designs on improving the seals and fuel injection. If only I had a few engineers, and some funding...
Mazda has supposedly solved the problem by moving the exhaust ports to the side of the rotor housing. This way the unburnt fuel stays in the combustion chamber to be burnt in the next cycle. They are claiming a 30% increase in efficiency while the engine is idling.
 

SagaLore

Elite Member
Dec 18, 2001
24,036
21
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Originally posted by: KnightBreed
Originally posted by: SagaLore
Well... no it isn't new. But it's still a fresh idea. The amount of time and effort put into the steam engine, then the otto-cycle internal combusion engine, it wasn't fair for the wankel to fail so fast. One of the arguments against the DKM wankel is that it actually consumed more fuel... but, a lot of the exhaust was unburnt fuel. So then to cope they ran the exhaust through a high-temp burner, which needed more fuel, to finish the burning. So you ended up with super clean exhaust and a lot of spent fuel. If they'd just improve the fuel/air ratio and work more on efficient thermal combustion inside the chamber, I think wankel would be #1 in fuel economy.

Years ago I came up with some pretty nice designs on improving the seals and fuel injection. If only I had a few engineers, and some funding...
Mazda has supposedly solved the problem by moving the exhaust ports to the side of the rotor housing. This way the unburnt fuel stays in the combustion chamber to be burnt in the next cycle. They are claiming a 30% increase in efficiency while the engine is idling.

Haven't the exhaust ports been on the side for quite some time?...

As far as the torque, the engine gets 270 degrees of a power stroke as opposed to 180 in a piston engine. The torque curve is mainly flat as you increase it's speed - wankels are power horses.

a good site monito.com
 
Jun 18, 2000
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Not on Mazda's engines. Every engine up to the 13B in the FD RX-7 had the intake ports on the side and the exhaust ports mounted peripheral to the rotor housing. Starting with the Renesis engine going into the RX-8, the exhaust ports will be mounted on the side with a ceramic coating on the inside (of the port cutout) to reduce heat. The Renesis is going to kick some serious ass.

Yea, the Renesis engine achieves 90% of its peak torque at like 3500 rpm, and stays relatively flat through 7000rpm. I forget the exact numbers, but there's a dyno of the RX-8's engine floating around the RX-8 Forum.
 

Triumph

Lifer
Oct 9, 1999
15,031
14
81
It seems to me that if you took the necessary steps to fix the problems with this engine, you'd just end up with a rotary...:confused:
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
The issue of the "flaps" slamming into the head .. isn't one, I mean, duh. If the guy designed an engine without taking that in mind.. :p

I believe this answers the question:
It is found in operation the amplitude of these oscillations should be controlled to get the required performance.Therefore the pinion, fitted at the end of oscillating shaft is engaging with a rack of gears attached to a connecting rod. The connecting rod is coupled to a freely driven crank gear, permitting the pinion and the shaft to oscillate within a defined amplitude.

I dunno. I just thought it was interesting. I'm all for new engine technology. That was my first thought too, how reliable would the whole oscillating mechanism be, given all the stress it would be subject too.

I'm sure the engine would run, and develop power.. The question is, how reliable would it be.

It's taken us some 150 years to get the traditional piston engine to a decent state, but it's still far from perfect.

We need to demand an engine that doesen't waste so much energy...
 

element

Diamond Member
Oct 9, 1999
4,635
0
0
Worst design I've ever seen. Who wants to bet that guy is either a layperson or chemically imbalanced?
 
Jun 18, 2000
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Originally posted by: element®
Worst design I've ever seen. Who wants to bet that guy is either a layperson or chemically imbalanced?
Its a clever design, for what it's worth. Can you do any better?
 

silent tone

Golden Member
Oct 9, 1999
1,571
1
76
Good point. As long as air or exhaust is in the chamber, and the valves were sealed properly, it'd be impossible for the flaps to slam into the head. But you're going to lose efficiency since some of the energy from the power stroke negated by the force of the compressed air opposite the flap.
Energy from the power stroke in a conventional piston engine is lost to the compression stroke, it's just that the compression is happening down the crankshaft in a separte cylinder, not on the opposite side of a 'flap' inside a 'barrel'

This page is pretty popular, second link in a google for 'internal combustion engine model'
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
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Originally posted by: KnightBreed
Originally posted by: element®
Worst design I've ever seen. Who wants to bet that guy is either a layperson or chemically imbalanced?
Its a clever design, for what it's worth. Can you do any better?

I agree. Let's see you do better.. lol..

I dunno. What's the practical limit, percentage, for converting heat energy into rotational energy?

A more efficent engine would certainly help things a lot.
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
Originally posted by: RaySun2Be
How's This for an interesting alternative. And look, they have a prototype. :)

Cool. It's good to know there are "amateurs" working on engine design. That seems to be how most things get invented, traditionally.

 
Jun 18, 2000
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Originally posted by: istallion

Energy from the power stroke in a conventional piston engine is lost to the compression stroke, it's just that the compression is happening down the crankshaft in a separte cylinder, not on the opposite side of a 'flap' inside a 'barrel'
Yes, but with an otto-cycle engine you likely have 5x the mass compressing the air/fuel. The lighter mass of each flap is more susceptible to the force of the compressed gases. Though, I guess you could just pump more gas into the chamber - more gas = more combustion force. *shrug* I still don't like the design. :)