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Delay ignition system " Free run cycle " for fuel saving'

Delay ignition system " Free run cycle " for fuel saving'

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Discussion

Ray Kan

Original Poster:

2 posts

Monday 2nd October
quotequote all
I was wondering, if some one could give me the exact feedback of the following ans.
1. 4 pistons with the firing orders 1 - 3 - 4 - 2 would it means 1, 2 piston at TDC ( Compression stage )and 3,2 piston at BDC ( Explosion stage) ?? Then how about 6 pistons with firing orders 1 - 5 - 3 - 6 - 2 - 4 Could it means 1,2,3 pistons at TDC and 4,5 ,6 at BDC . Piston 1,2,3 fire at the same time or one after another ?? Of cause firing orders of piston will be equalize and balancing avoiding engine vibration.
2. As piston from explosion, exhaustion, compression stage till next explosion again.The energy conceive still powerful enough before next explosion stage. Because constraint by the crank shaft it self in rotation way of moving, energy are wasted. What I mean, why not prolong the ignition stage a few " Free run cycle " before next ignition start. Of cause intake valve will be control by solenoid for shutting off supply during " free run cycle " and the Compression force will be neglected as air quite elastic. So the " Free run cycle " could be prolong much longer if travelling speed exceed 100 km/hr. On the whole the" Delay ignition system " will be control by micro chip or could be manual when vehicle travelling speed over 100 km/hr. In theory the faster the speed more cycle needed and petrol consume much more.
censored

ETA

Sorry, not allowed.



Edited by Big Al. on Monday 2nd October 12:34

Buff Mchugelarge

3,096 posts

72 months

Monday 2nd October
quotequote all
So if I understand correctly, using the momentum of the crank/ piston to save fuel by not having an ignition at tdc?
I think between shutting down cylinders (v8's and V6's) and not injecting fuel on a closed throttle we're pretty much there?

gazza285

3,534 posts

130 months

Monday 2nd October
quotequote all
Ye cannae change the laws of physics...

Max_Torque

11,562 posts

139 months

Monday 2nd October
quotequote all
i take it you've not heard about the electric revolution?

No one GAS about old noisy, smelly, wasteful DinoJuice burners anylonger..... ;-)

996TT02

2,196 posts

62 months

Monday 2nd October
quotequote all
Apart from the fact that no it does not work like that - in a 6 cyl (or any other) you don't get half the pistons firing and half at BDC. Even with a flat plane crank pistons at TDC would either be exhausting/intaking or compressing/igniting. With more than 4 cylinders, the crank angles are usually equally divided for smoothness. If you missed a firing cycle (if that is what I understand you mean to say) then the piston's extra two up-downs would just be drag and the active piston would need to use more fuel/air to maintain the required power output.
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Ray Kan

Original Poster:

2 posts

Monday 2nd October
quotequote all
Let's interpretation more simple of what I think the energy not fully utilized by 4 stroke engine.
1. Imagine if Piston were put in a long barrel with same diameter and compression with petrol/air mixture. After ignition, piston sure traveling a very long distance before it stop. So for 4 stroke engine the Piston traveling path is within a lope and it travel only very short distance and again intake fuel for second ignition and I think energy not fully released before 2nd ignition.
2. What I'm saying is when traveling at 100 km/hr , sure it's momentum would great enough to sustain moving. why not having a long interval " Free Run " before ignite again instead of just a cycle. So faster it's traveling much longer " Free Run " acquire and more fuel saving.
3. By utilizing micro chip for monitoring ignition timing, we could setting timing for interval " Free Run "
4. During " Free Run " stage, no intake of fuel as solenoid closed and momentum is great enough to let Piston back to TDC without really loosing power.
5. I think it's much easier to start with motor bike for modification of this " Delay ignition system "
6. Those day during 2nd World War Nazi invented a very long barrel cannon build on hilltop. It's principle is to apply side chamber with explosive at interval length to blast off passing by shell, thus speed of shell would be tremendously fast at final stage in order to hit London. Compare to 4 stroke engine , why with so many ignition stage speed still at constant. I think energy confine and wasted in a lope " hold by crank shaft " and intake , compression procedure . Just a very much short timing It got to take in fuel and ignite again with energy still great enough.

Edited by Ray Kan on Monday 2nd October 18:17

tvrolet

3,146 posts

204 months

Monday 2nd October
quotequote all
As I'm sure you know, most petrol engines run on the Otto-cycle (and no, 6 cylinder engines don't work 3 up and 3 down)...

What you seem to be describing sounds like a modern Atkinson-cycle, which I believe Toyota are putting in a few cars (or will be soon). Read up on it - it's been done, and someone's undoubtedly got the tee-shirt.

Max_Torque

11,562 posts

139 months

Monday 2nd October
quotequote all
You're about 15 years too late:

5_stroke_engine




and no, you can't do it with just retarding the ignition (because you need to change the geometric expansion ratio or the valve timing to bias the stroke away from the mean)

gazza285

3,534 posts

130 months

Monday 2nd October
quotequote all
Ray Kan said:
Let's interpretation more simple of what I think the energy not fully utilized by 4 stroke engine.
1. Imagine if Piston were put in a long barrel with same diameter and compression with petrol/air mixture. After ignition, piston sure traveling a very long distance before it stop. So for 4 stroke engine the Piston traveling path is within a lope and it travel only very short distance and again intake fuel for second ignition and I think energy not fully released before 2nd ignition.
2. What I'm saying is when traveling at 100 km/hr , sure it's momentum would great enough to sustain moving. why not having a long interval " Free Run " before ignite again instead of just a cycle. So faster it's traveling much longer " Free Run " acquire and more fuel saving.
3. By utilizing micro chip for monitoring ignition timing, we could setting timing for interval " Free Run "
4. During " Free Run " stage, no intake of fuel as solenoid closed and momentum is great enough to let Piston back to TDC without really loosing power.
5. I think it's much easier to start with motor bike for modification of this " Delay ignition system "
6. Those day during 2nd World War Nazi invented a very long barrel cannon build on hilltop. It's principle is to apply side chamber with explosive at interval length to blast off passing by shell, thus speed of shell would be tremendously fast at final stage in order to hit London. Compare to 4 stroke engine , why with so many ignition stage speed still at constant. I think energy confine and wasted in a lope " hold by crank shaft " and intake , compression procedure . Just a very much short timing It got to take in fuel and ignite again with energy still great enough.

Edited by Ray Kan on Monday 2nd October 18:17
But while that cylinder is in "free run" it is not contributing to the forward motion of the vehicle, so the other cylinders have to provide more power, thus consuming the fuel saved by turning a cylinder off. The vehicle still needs the same power to sustain its speed.

GreenV8S

24,745 posts

206 months

Monday 2nd October
quotequote all
It's hard to make sense of the original post but it reads vaguely like a hit-and-miss engine i.e. where power is reduced by skipping a power cycle.

AER

863 posts

192 months

Tuesday 3rd October
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Max_Torque said:
You're about 15 years too late:

5_stroke_engine
You can do the same thing with a turbine hanging off the exhaust. Of course, the complexity is in compounding it to generate mechanical work but a solution to this is what the F1 boys are using with the MGU-K and MGU-H or whatever they call them.

Max_Torque

11,562 posts

139 months

Tuesday 3rd October
quotequote all
AER said:
Max_Torque said:
You're about 15 years too late:

5_stroke_engine
You can do the same thing with a turbine hanging off the exhaust. Of course, the complexity is in compounding it to generate mechanical work but a solution to this is what the F1 boys are using with the MGU-K and MGU-H or whatever they call them.
Indeed, and reaching (a claimed) 50% Thermal Efficiency with it!

(the £££ per joule efficiency is rather low though..... ;-)

gazza285

3,534 posts

130 months

Tuesday 3rd October
quotequote all
Max_Torque said:
You're about 15 years too late:

5_stroke_engine




and no, you can't do it with just retarding the ignition (because you need to change the geometric expansion ratio or the valve timing to bias the stroke away from the mean)
Same theory as a compound steam engine, so more like 230 years too late.

AER

863 posts

192 months

Thursday 5th October
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Max_Torque said:
(the £££ per joule efficiency is rather low though..... ;-)
Improving the thermal efficiency of heat engines to extremes usually is (very) expensive

Mr2Mike

17,669 posts

177 months

Friday 6th October
quotequote all
gazza285 said:
Same theory as a compound steam engine, so more like 230 years too late.
yes Compound internal combustion engines have been around for a long time as well, the German Deutz company made one back in 1879, and numerous others followed. The "five stroke" concept isn't even remotely new or novel.