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  #61  
Old 02-27-2006, 10:53 AM
stian1979 stian1979 is offline
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[QUOTE=Matra et Alpine]
Quote:
Originally Posted by stian1979
If you use a electric engine it will require more power when you acelerate.
To suply more power the load on the stirling has to increase and because of the stirlings slow response to load changing it would drop in speed (just read about diesel generator's and speed drop).
A battery package would prevent this, but ad extra weight.[/quote}
Correct, btu if it is only required for short periods it does NOT as larege a penalty. It's only needed for averaging the peak needs withthe average output fo a VERY efficient engine. I thought that was obvious

Careful.
DAF had been racing the CVT inf F3 - we've talked abotu it before on UCP with pics - and Frank worked with them to TEST it. Whether it actually delevered any benefit for the weight and stresses was never published and the FIA banned it before it
DC test drove the one in '93


The FIA banned CVT as they felt it took away from the driver. Not for technical reasons. So it never went any further. So we never knew whether it was able to handle the torque lash of kerbs corner on full throttle or if it lasted 2 hours.

Where did you find a reference to it actually HANDLING the 700HP for duration ???


It's NOT easy to "balance" an engine. Even the best balancer shafts have recognised frequencies in the engine where they are inneffective due to harmonics.
But the Revetec doesnt' need contra-rotating balanceshafts as it isnt' trying to balance a ROTATING mass. You dont' seem to grasp the difference

By the time you get to the point in the curve you have used up ( or should have ) the expansion of the gasses - with a little left over to assist exhaust flow ). So you are mathematically correct if you were running an engine driven by compressed air. But you're not. You are running a COMBUSTION engine which has a peak pressure which drops as the piston recedes. As I said before, you seem to only see one thing at a time. Each thing on it's own is valid. BUT when you take the other factors into account aren't .

They're not. THere are plenty of companies producing new engines on a regular basis.
PS: 2-strokes can't clean up emissions without major post combustion management. You can't burn heavy lubricating oils wihtout emission problems. Sadly nobody wants to invest in finding solutions.
DC put in some impresive lap times with the CVT in testing.

To acelerate a famely van it take some power so batterys had to have a size that would ad weight and take away space. A famely car of some size 1500kg from 0-100km/h in 11 secs nead some power and if you got batterys fully loaded and acelerate to 80km/h and a dude runn into the road so you got to brake. Then you step on it again and at 90km/h the car just die because batterys are runn empthy and the stirling stil did not get up too speed yet so you are limited to 50km/h and slovly acelerating until you reatch 100km/h.

I got more belif that it has to be combined with a traditional combustion engine. Maybe a combustion engine only enabled on city driving and aceleration, disabled during freeway. who konw.

So with out balance shafts, how will you make the forces from the pistons not to ad vibration? This is not a boxer in case you did not notice so both pistons move toward's the same side at the same time. If the engine was constructed without conrods just like the revetec is and at the same time was able to make pistons move towards eatch other like a boxer no balancing would be required. Since the crankshaft rotate 1 per 3 work cycles counter weights can not be added to this, some thing you see is obious so it will nead a balance shaft to balance out the oscilating movements from pistions. Rotating alancing is not a problem like the traditional conrods I can agree.

1/2 of the conrod is considered to be oscilating and the other 1/2 is considered to be rotating. I did my homework on this, probartly the only thing about engine dynamics I still remember.

2-strokes are the moust inviromental engines. You don't find anny engine more fuel efficiant than sulzer or B&W 2-strokes. consumtion of cylinder lube oil is a problem caused by the fact that no syntetic oil is made for this purpose. No ship owner want to buy syntetic oil for this purpose since it will cost him soo mutch that he's compatitors will get the contracts.

About cylinder preshure I'm right. Even the preshure drops by 50% I will stil have 50% longer arm than the revetec. It all ends up in the same in the end. The only advantage by geting long arm at a earlier stage is that not that mutch energy has escaped trough the top and cylinderwals yet, but this problem is smal and will be solved at once the customers are willing to pay for cheramic and insolated engines due to fuel prices. There is no practical reason for adapting this design. I like it, it's a funn concept, but it's also all it is.

I'm stil concerned about the bearing. Not anny ball bearing is 100% round, maybe it is 99,9999999%, but not 100% ball barings don't handle the same load as a plain baring and if anny contamination in the oil like soot or other particles it will just dig into the plain bearing and do no futher harm.
A ballbearing can more easely get permanent problems witch I'm shure you are avear off.
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  #62  
Old 02-27-2006, 11:13 AM
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Matra et Alpine Matra et Alpine is offline
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[quote=stian1979]
Quote:
Originally Posted by Matra et Alpine

DC put in some impresive lap times with the CVT in testing.
You got any actual figures.
All that I remember about it was platitudes.
ANd nobody says theire idea is a dog
Quote:
To acelerate a famely van it take some power so batterys had to have a size that would ad weight and take away space. A famely car of some size 1500kg from 0-100km/h in 11 secs nead some power and if you got batterys fully loaded and acelerate to 80km/h and a dude runn into the road so you got to brake. Then you step on it again and at 90km/h the car just die because batterys are runn empthy and the stirling stil did not get up too speed yet so you are limited to 50km/h and slovly acelerating until you reatch 100km/h.
You are AGAIN thinking of only one issue at a time>
The problem is only when you first start up. AS SAID, you would size the battery to manage the peak. You dont' accelerate a car for 20 seconds
Sorry but you're missing the whole point by being single-thinking. Build in what the Stirling engien is doing durign the acceleration of the vehicle and what it is doing durign coast and steady speed ?
Nobody's sayign there are NO batteries but it wouldn't need the SHED LOAD that current hybrids are running
Quote:
I got more belif that it has to be combined with a traditional combustion engine. Maybe a combustion engine only enabled on city driving and aceleration, disabled during freeway. who konw.
Even if allowed to run at optimim efficiency, then an Otto will be WELL short of the efficiency of a Stirling -- or another "imporoved" combustion engien
Quote:
So with out balance shafts,
First balancer shafts are requried because of the ROTATION rpbblems.
Do you grasp that ?
So it is ONLY reciprocating weight that is the problem and the only part of a Revetec is the PISTON -- no strong conrod or crank out there
So you first recognise that it's a fraction of teh nromal engien weight. So you've done THE MOST IMPORTANT step already which is minimising the mass. Then if necessary they would apply for balance by multiple cylinders -- jstu in teh same way a V8 manages optmimum any paired Revetec piston seupt should.
Quote:
1/2 of the conrod is considered to be oscilating and the other 1/2 is considered to be rotating. I did my homework on this, probartly the only thing about engine dynamics I still remember.
That's a simplification that only works as long as you're not trygin to maximise the power output or the efficiency. Sadly I believe you've forgotten more than you think
[quote]2-strokes are the moust inviromental engines.[/quote}
BS and you provide the answer yourself - as I had already said.
Quote:
consumtion of cylinder lube oil is a problem caused by the fact that no syntetic oil is made for this purpose.
Rubbish You can't make an oil have long chains to maxinmise lubrication AND burn efficiently. You are thinking of only one thing at a time again.
let's now jsut save me the hassle. You're wrong.
Quote:
About cylinder preshure I'm right. Even the preshure drops by 50% I will stil have 50% longer arm than the revetec. It all ends up in the same in the end.
NO it doens't !!!
You are wrong.,
You are NOT thinking of the whole system again>
A crank does not match the optimal piston pressures because of the angles !! This is what the Revetec designer ( and many others over hte decades ) is trying to recover energy better.
Sorry, think about the CRANK positin as well as piston and do the vector force calucaltion and see how much is goin in to provide OUTPUT force.
Quote:
There is no practical reason for adapting this design. I like it, it's a funn concept, but it's also all it is.
Because you've NOT actually looked at the force vectors in all the components.
Do it, you will learn and understand.
Quote:
I'm stil concerned about the bearing. Not anny ball bearing is 100% round, maybe it is 99,9999999%, but not 100% ball barings don't handle the same load as a plain baring and if anny contamination in the oil like soot or other particles it will just dig into the plain bearing and do no futher harm.
A ballbearing can more easely get permanent problems witch I'm shure you are avear off.
Yeah but why is a ball bearing coming in to it ?
Do you mean NEEDLE bearings ?
Needle bearings can handle the pressures.
I think you are still thinking of only one thing at a time. Different materials could provide it, perhaps sacrificial. Oil bath coud deliver it at higher speeds onto the mating surface. WOudl still need strong material tho as it won't benefit from pressure build up from rotation the way a crank does.
But as you are not clearly aware the forces beign talked abotu are the SAME as a normal Gudgeon Pin on a piston is handling
So how come it survives there and yet won't here ??
MATERIALS and oil supply -- the challenge will be having ENOUGH pressure to ensure a minium thicnkess of oil to ride on.
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Last edited by Matra et Alpine; 02-27-2006 at 11:26 AM.
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  #63  
Old 02-27-2006, 12:35 PM
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Actually Matra the most efficient ICE in the world is a super huge 2 stroke diesel.

other than that Matra has done a good job pointing out innaccuracies I just like the fact that I have a design change that could allow the revetec to do so much better (reducing vibration, increase output speed, Improve lever length, lower weight, and it might just improve combustion?)
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  #64  
Old 02-27-2006, 02:54 PM
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Matra et Alpine Matra et Alpine is offline
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Quote:
Originally Posted by hightower99
Actually Matra the most efficient ICE in the world is a super huge 2 stroke diesel.
Yeah but this isn't ultimateSHIPpage.com despite some of Matt's recent postings And ships can put huge scrubbers in the exhaust !!
One of the most efficient two strokers was the 1960s Honda 50cc race engine.
Revved to 24,000 needed 12 gears to be usable but SOUNDED SUPERB
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  #65  
Old 02-27-2006, 08:03 PM
stian1979 stian1979 is offline
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Quote:
Originally Posted by Matra et Alpine
You got any actual figures.
All that I remember about it was platitudes.
ANd nobody says theire idea is a dog

You are AGAIN thinking of only one issue at a time>
The problem is only when you first start up. AS SAID, you would size the battery to manage the peak. You dont' accelerate a car for 20 seconds
Sorry but you're missing the whole point by being single-thinking. Build in what the Stirling engien is doing durign the acceleration of the vehicle and what it is doing durign coast and steady speed ?
Nobody's sayign there are NO batteries but it wouldn't need the SHED LOAD that current hybrids are running

Even if allowed to run at optimim efficiency, then an Otto will be WELL short of the efficiency of a Stirling -- or another "imporoved" combustion engien

First balancer shafts are requried because of the ROTATION rpbblems.
Do you grasp that ?
So it is ONLY reciprocating weight that is the problem and the only part of a Revetec is the PISTON -- no strong conrod or crank out there
So you first recognise that it's a fraction of teh nromal engien weight. So you've done THE MOST IMPORTANT step already which is minimising the mass. Then if necessary they would apply for balance by multiple cylinders -- jstu in teh same way a V8 manages optmimum any paired Revetec piston seupt should.

That's a simplification that only works as long as you're not trygin to maximise the power output or the efficiency. Sadly I believe you've forgotten more than you think
2-strokes are the moust inviromental engines.
BS and you provide the answer yourself - as I had already said.

Rubbish You can't make an oil have long chains to maxinmise lubrication AND burn efficiently. You are thinking of only one thing at a time again.
let's now jsut save me the hassle. You're wrong.

NO it doens't !!!
You are wrong.,
You are NOT thinking of the whole system again>
A crank does not match the optimal piston pressures because of the angles !! This is what the Revetec designer ( and many others over hte decades ) is trying to recover energy better.
Sorry, think about the CRANK positin as well as piston and do the vector force calucaltion and see how much is goin in to provide OUTPUT force.

Because you've NOT actually looked at the force vectors in all the components.
Do it, you will learn and understand.

Yeah but why is a ball bearing coming in to it ?
Do you mean NEEDLE bearings ?
Needle bearings can handle the pressures.
I think you are still thinking of only one thing at a time. Different materials could provide it, perhaps sacrificial. Oil bath coud deliver it at higher speeds onto the mating surface. WOudl still need strong material tho as it won't benefit from pressure build up from rotation the way a crank does.
But as you are not clearly aware the forces beign talked abotu are the SAME as a normal Gudgeon Pin on a piston is handling
So how come it survives there and yet won't here ??
MATERIALS and oil supply -- the challenge will be having ENOUGH pressure to ensure a minium thicnkess of oil to ride on.
No I'm not thinking at one thing at the time, but you are or like to think I am.

If you during aceleration neads to brake down because of a unekspected event and the acelerate again, your batteries would runn empthy befour the stirling would be able to take the load. Why do you think your so smart? don't you think there would be a hybrid stirling on someones model program allready if it was sutch a smart idea or are you one of those that belive there is a big conspiracy to keep up the oil price and sale?

A stirling is relative easy to build and sheap so it's clearly not a good idea since no one used it. I only see them as a way of energy recovery. Maybe you think that this hybrid thing is a new thing, but in the shipindustrie diesel generators running electric motors are a old idea from 1940. It only have advantage in load changing contitions and If the Stirling was a great idea This is probartly the place it would pop up first.

Yes I do understand that 1/2 and 1/2 is the simplefyed version, but do I really have to feed you everything in detail?
I understand why we got balance shafts and I also understand why counter weights are added to the crank. It's to counteract oscilating forces from the piston and 1/2 of the conroad(simplefyed version) How do you plan to fitt them to a revetec crank??? How will you counteract forces with a counter weight on a shaft rotating 1 time for every 6 time the force is aplied?
If you had a 4-cyl the engine would twist so to make vibrations not bother driver or/and pasangers you would nead a flat 8 who the hell would put that into there car?Packaging like you have pointed out yourself.
Just in case you stil don't understand the diference bewen a boxwe and a revetec.

Packaging like you have pointed out yourself.

Nedle bearing's solve one problem, but only one. They still are not that happy about contamination in the oil unlike plain bearings that can handle some of it. They are just like the ballbearing not 100% round and you ad two new disadvantages and that is that they can't handle that high speed's and if they go wrong they can relly go wrong.
If you want to adapt plain bearing's for this aplication how would you do that? How do you want to make the surface big enough to get a hydrodynamical lubrication that will not brake. Maybe you think I only think at one thing at the time and I think you come up with problems instead of sulutions.

Again there is no gain in this construction. The only smal gain is that it can make heat from combustion into work befour it transmits into the cooling system. This is a peoblem that will be solved annyway when the fuel price make ceramics worth there price. I can also ad to the discusion that fuel don't exsplode, but it combust. At the time 40-50% of the stroke is done it's stil hydro carbons burning and ading energy and at this time the convencional crank is at it's maximum angle. so this is energy the revetec will transforme into rotation when it has only 50% of it's optimal angle.

1-1=0

P.S clearly your knowledge about 2-strokes is limited to Honda MB-5 and Yamaha DTR-50.
Did you hear about Cumer, Wickmann, B&W, Sulzer, Detroit Diesel or GM Diesel at all?
About the lubrication oil for cylinders You defently not know what this is about, do you really think that all two strokes use oil mixed in there fuel? Worng! as for using syntetic oil I actualy atended a cource with Mobil Oil where use and qualety of oil's where the ishue. If you can use a syntetic oil you can get a bether lubrication so you can use less oil to do the same job and that will my friend reduce the problem of burned oil. Do some back ground studys befour opening you mouth.

Last edited by stian1979; 02-27-2006 at 09:12 PM.
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  #66  
Old 02-27-2006, 09:23 PM
stian1979 stian1979 is offline
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Lets say you are corect about the revetec. It delivers 3times the torque.

If a normal engine has a 30% efficensy and the revetec is able to transform 3 times more of the combustion into torque it would mean a efficensy of 90%
WOW!

I can actualy use the cooling water to wash a babys but and put my balls on the headers without feeling anny discomfort.
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  #67  
Old 02-28-2006, 03:41 AM
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Quote:
Originally Posted by Matra et Alpine
Yeah but this isn't ultimateSHIPpage.com despite some of Matt's recent postings And ships can put huge scrubbers in the exhaust !!
One of the most efficient two strokers was the 1960s Honda 50cc race engine.
Revved to 24,000 needed 12 gears to be usable but SOUNDED SUPERB
What??? I don't think so they guzzeled gas and oil like crazy for thier power output! The super large diesel I am talking about can reach 50% thermal efficiency!

Why is everybody still thinking about Stirlings and ceramic composites??? really people those are the old guesses at how to solve the heat problem but I know of a much better solution. A no-loss water injection system! inject water just as ignition is starting and most of the heat will be transformed into greater pressure, then you can have a lighter block and no radiators. (I hope everybody realises that it is not the heat but the pressure that makes things go round)

about the revetec vibrating too much, stian1979: the revetec can be made so that the pistons move just like in a normal boxer! (without all the side loading of course!)

Quote:
Originally Posted by stian1979
Again there is no gain in this construction.
this statement is full of bologna! There is quite a nice gain in the revetec construction (flawed as it is)
Quote:
Originally Posted by stian1979
The only smal gain is that it can make heat from combustion into work befour it transmits into the cooling system. This is a peoblem that will be solved annyway when the fuel price make ceramics worth there price.
this statement shows that you misunderstand where the advantage lies in the revetec. Revetec is better because it transforms reciprocating motion into rotary motion at greater efficiency when there is much higher pressures in the cylinder! In fact it has a higher conversion efficiency at all times! The revetec represents a mechanical change to get higher mechanical efficiency, nowhere does it say that suddenly more heat is made into work (this is not how ICEs work!) And ceramics wil not change the world at all as it doesn't stop the heat from getting out anyways (ever heard of an exaust valve?)

Quote:
Originally Posted by stian1979
I can also ad to the discusion that fuel don't exsplode, but it combust. At the time 40-50% of the stroke is done it's stil hydro carbons burning and ading energy and at this time the convencional crank is at it's maximum angle. so this is energy the revetec will transforme into rotation when it has only 50% of it's optimal angle.
This is an irrelavant and partially untrue statement. A good engine will combust more than 80% of the fuel in the cylinder before 20 deg ATDC the remaining power from the remaining gas is not enough to keep the pressure high through the expansion phase!(in other words the remaining gas doesn't add any power it simply slows the loss) Most conventional crank engines reach maxium conversion efficiency at around 60deg not 90deg like you think they do. And what are you talking about 50% of it's optimum angle?? the optimum angle is 90deg to radius this doesn't change for any engine! the revetec is always at about 90deg to the radius of the lever arm! (actual range is about 75-90deg when the piston is moving)

Quote:
Originally Posted by stian1979
Lets say you are corect about the revetec. It delivers 3times the torque.

If a normal engine has a 30% efficensy and the revetec is able to transform 3 times more of the combustion into torque it would mean a efficensy of 90%
WOW!

I can actualy use the cooling water to wash a babys but and put my balls on the headers without feeling anny discomfort.
this is about as missled as I care to read. the 30% efficiency you are talking about in a normal engine is the thermal energy. (as in theretical total energy of fuel used divided by the output energy) the revetec is 3 times more mechanically efficient not thermally! you are relating numbers and doing top of the head math that shouldn't be! Both the revetec and a normal engine have the same amount of waste heat!
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  #68  
Old 02-28-2006, 04:26 AM
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Matra et Alpine Matra et Alpine is offline
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Quote:
Originally Posted by hightower99
What??? I don't think so they guzzeled gas and oil like crazy for thier power output!
No they didnt'.
They competed the Isle of Man TT race on the SAME FUEL as their competitors and did it minutes faster
Also able to come back 40 years later and STILL rev to 20,000. All in a small town square with the sound echoing around :drool:
But you are right compared to TODAYS 2-strokes they ate oil. The Honda ceramic engine solved that -- but unfortunatley blew up every time it raced
Quote:
The super large diesel I am talking about can reach 50% thermal efficiency!
Good point, I was stuck thinking petrol. Two stroke diesel better for sure
Quote:
Why is everybody still thinking about Stirlings and ceramic composites???
The Stirling is only going around because I picked the most ridiculous engine to operate a car with, but one with the capacity for the highest energy extraction.
Quote:
A no-loss water injection system! inject water just as ignition is starting and most of the heat will be transformed into greater pressure, then you can have a lighter block and no radiators.
But you also create acidic compounds and cause emissions issues. Can't remember the mix but it's not easy to remove needing two stage catalytics IIRC. It became a dead end for the car makers.
( Mind you with modern injection and better CFD in cylinder design -- maybe .... hmm got me thinking there, ht, any links to anyone doing current development ?? )
[/quote](I hope everybody realises that it is not the heat but the pressure that makes things go round)[/quote]
I think so because we've all been talking about pressure





Thanks for the rest, th, I'm close to delivering a MetA "response" to Stian who isn't listening and in his response where he SAYS he isn't thinking about one thing at a time goes on to prove it. You words were kinder than I would have managed this time around.

stian -- you are wrong. The evidence has been presented. My parting comment to you .... learn about the difference between peak and average and you would understand the Stirling/Hybrid and realise the HUGE mistake The rest of it ?? .... listen to ht
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  #69  
Old 02-28-2006, 05:58 AM
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Quote:
Originally Posted by Matra et Alpine
But you also create acidic compounds and cause emissions issues. Can't remember the mix but it's not easy to remove needing two stage catalytics IIRC. It became a dead end for the car makers.
( Mind you with modern injection and better CFD in cylinder design -- maybe .... hmm got me thinking there, ht, any links to anyone doing current development ?? )
this is what happened in the past. I believe that with a synthetic oil and better ring seal technology (it exists it just has to be used) that oil and water can be kept seperate for the most part and that when they do meet that they do not produce nasty compounds. I don't know of anyone looking into it right now, but I plan to try some test systems out on a turbo diesel. (When I turn the key what will happen?)

also I am talking about water injection as an entire cooling system not a intercooler or whatever.

also a good note that with water injection cooling with a no-loss system (as in you don't need to keep filling up on water) then efficiency can be raised very high as it is theretically possible to have exaust temperatures that are lower than intake after turbocharging temperatures. (a theretical but believeable example would be exaust temp of 20deg C and a intake after turbocharging temp of 300deg ((no intercooler)))
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Last edited by hightower99; 02-28-2006 at 06:01 AM.
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  #70  
Old 02-28-2006, 07:01 AM
stian1979 stian1979 is offline
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Quote:
Originally Posted by hightower99
What??? I don't think so they guzzeled gas and oil like crazy for thier power output! The super large diesel I am talking about can reach 50% thermal efficiency!
They are actualy betwen 50-55% nowdays.

[QUOTE=hightower99
Why is everybody still thinking about Stirlings and ceramic composites??? really people those are the old guesses at how to solve the heat problem but I know of a much better solution. A no-loss water injection system! inject water just as ignition is starting and most of the heat will be transformed into greater pressure, then you can have a lighter block and no radiators. (I hope everybody realises that it is not the heat but the pressure that makes things go round)[/QUOTE]

Water injection prove to giwe lover emisions but only 5-15% will give a power increase since more than that only will cool down the gasses to mutch and you will not have a power loss instead. Heat don't make things go around? Do you know that if air dubble it's temperature it will grow to 5 times the volum? This means that preshure will increase if the air has nowhere ti exspand.

Quote:
Originally Posted by hightower99
about the revetec vibrating too much, stian1979: the revetec can be made so that the pistons move just like in a normal boxer! (without all the side loading of course!)
Yes it can, but now it's geting more heavy again

Quote:
Originally Posted by hightower99
A good engine will combust more than 80% of the fuel in the cylinder before 20 deg ATDC the remaining power from the remaining gas is not enough to keep the pressure high through the expansion phase!(in other words the remaining gas doesn't add any power it simply slows the loss) Most conventional crank engines reach maxium conversion efficiency at around 60deg not 90deg like you think they do.
Diesel don't and this will probartly be the engine that will be more and more dominat because it don't bother that mutch about fuel qualety. You can runn it on LNG or asfalt(if you heat it up to 170C) Why do you thing big diesels at 10MW ++ has long stroke? Lots of rasons, but one of the is that it gets time to burn things that normal engines would not be able to combust.

Quote:
Originally Posted by hightower99
this is about as missled as I care to read. the 30% efficiency you are talking about in a normal engine is the thermal energy. (as in theretical total energy of fuel used divided by the output energy) the revetec is 3 times more mechanically efficient not thermally! you are relating numbers and doing top of the head math that shouldn't be! Both the revetec and a normal engine have the same amount of waste heat!
Yeah right. I would like to see a engine provide "3" times the torque at the same fuel consumption, same outer crank diameter and same heat loss. If they say a 5% or even 20% Increase due to bether transfere of forces I could buy it, but 3 times no. Sorry hightower.Scotch Yoke kan do the same just as good.

Quote:
Originally Posted by Matra et Alpine
stian -- you are wrong. The evidence has been presented. My parting comment to you .... learn about the difference between peak and average and you would understand the Stirling/Hybrid and realise the HUGE mistake The rest of it ?? .... listen to ht
I know about all this mathers so I dear to say you are wrong. You have ben reading to mutch on revetec.com and svoloved the bait with the hock, line and maybe even the fisher. Try to make this engine yourself and runn it in MSC Adams. You still think your the tecnical Albert Einstein so why are no one running Hybrid Stirlings now? Do you belive in conspiracy to keep oil consumtion up and oil price up? If Stirling was so perfect as you try to make it seam every one would have a stirling hybrid in there model programe now.

If your only going to start it up and drive normaly to work it will probartly work just fine, but if you got to brake down to a dear crosing the road after only 30 secs of driving and then acelerate again the stirling would stil strugle to take load and the batterys would be empthy. It's not every day driving My consern is, but things that hapend that you did not exspect in the first place. This could be solved by using the electric motor as a generator to brake the weel's and runn the power to bateries by excitation of the motors, but now costs and system compeksety rise.

So strange the car industri don't jump on to your ideas of perfect engines and sulutions if they are so great.

Quote:
Originally Posted by hightower99
this is what happened in the past. I believe that with a synthetic oil and better ring seal technology (it exists it just has to be used) that oil and water can be kept seperate for the most part and that when they do meet that they do not produce nasty compounds. I don't know of anyone looking into it right now, but I plan to try some test systems out on a turbo diesel. (When I turn the key what will happen?)

also I am talking about water injection as an entire cooling system not a intercooler or whatever.

also a good note that with water injection cooling with a no-loss system (as in you don't need to keep filling up on water) then efficiency can be raised very high as it is theretically possible to have exaust temperatures that are lower than intake after turbocharging temperatures. (a theretical but believeable example would be exaust temp of 20deg C and a intake after turbocharging temp of 300deg ((no intercooler)))
Like I say befour in this post it's limited how mutch you can spray in of water. If you increase preshure water will avaporate at a higher temperature. 60bar preshure is enough to keep water from not boiling even at 200C++

Also it has some other effects. H2O+Fe=? and heat make it go faster. And if it get out of the cylinder into the engine you have something called hydrocarbons or oil. H2O + hydro carbons can make organic acid's and I would not like that in my engine. Ceramics are interesting. No cooling neaded and you can wrap in the engine with insulation and water will not be a ishue if cylinder components are made from material that don't rust.

Last edited by stian1979; 02-28-2006 at 07:11 AM.
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  #71  
Old 02-28-2006, 08:29 AM
stian1979 stian1979 is offline
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http://www.autoblog.com/2005/12/09/b...-hot-and-goes/ some one got there eyes up for the future as I see it. Heat recovery.
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Old 02-28-2006, 09:17 AM
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Matra et Alpine Matra et Alpine is offline
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Quote:
Originally Posted by hightower99
oil and water can be kept seperate for the most part and that when they do meet that they do not produce nasty compounds.
I was meaning IN the combusino chamber and the mix of air and fuel.
Partial combustion generates acid compunds rahtehr than free gasses. So when it gets to teh catalyst, furirst it's done dmamge on teh way and second the catalyst has to first break down the acid and THEN combine to stabilise.
Quote:
also I am talking about water injection as an entire cooling system not a intercooler or whatever.
A given, intercooling and charge cooling are well undestood and used.
Quote:
also a good note that with water injection cooling with a no-loss system
Ohhh, wasn't thinking zero-loss
So how do you recover the water ?
Especially as some of it WILL have combined to form acid compounds.
How much energy does it take to keep a cold surface condensor cold ??
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Old 02-28-2006, 09:19 AM
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Matra et Alpine Matra et Alpine is offline
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Quote:
Originally Posted by stian1979
http://www.autoblog.com/2005/12/09/b...-hot-and-goes/ some one got there eyes up for the future as I see it. Heat recovery.
We discuss ed this one before.
Difficult to see how much it really benefits given teh extra weight it's carryign around
Seemed like it really would need triple expansion to recover more to warrant the weight. ( My subconscious has worked on that to and it woudln't work as it's NOT high pressure so the last piston would need to be the size of a large bucket )
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Old 02-28-2006, 12:41 PM
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to reply partly off-topic:

The gains of the CVT in the DAF f3 (or was it an f2 car ?) car were around and about 34-36 percent.On certain tracks even as high as 45-50% !!! No shifting time meant a huge advantage. DAF was planning more racing and sports activities to approve their image (especially in holland) before the passenger vehicle part of the company went bust and these racing activities were also cancelled. The CVT was used in the f3/f2 cars cos of the low amount of power. at the time a max. of 250 hp was there There are cvt's used in (experimental) trucks which have power up to 1000-1500 hp
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Old 02-28-2006, 12:50 PM
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Matra et Alpine Matra et Alpine is offline
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Quote:
Originally Posted by drakkie
to reply partly off-topic:

The gains of the CVT in the DAF f3 (or was it an f2 car ?) car were around and about 34-36 percent.On certain tracks even as high as 45-50% !!! No shifting time meant a huge advantage.
Not really.
www.f3history.co.uk/Manufacturers/DAF/daf.htm


Quote:
DAF was planning more racing and sports activities to approve their image (especially in holland) before the passenger vehicle part of the company went bust and these racing activities were also cancelled.
The racing was cancelled LONG before DAF went bust.
Quote:
The CVT was used in the f3/f2 cars cos of the low amount of power. at the time a max. of 250 hp was there There are cvt's used in (experimental) trucks which have power up to 1000-1500 hp
Yeah but those dont' use belts (or they didnt' used to ) and so the losses in the transmission are quite high. Big and heavy too. Not an issue in a truck
Got any links for the progress on the experiments as it' skind of gone quiet
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