New ICE engine design promises up to double the fuel efficiency 75 to 100 mpg. -(this not a joke)

[JohnWxy]

http://www.bendbulletin.com/apps/pbcs.dll/article?AID=/20070522/BIZ0102/705220334

In essence, Raether says he has developed a more efficient way to transform linear power - the drive of a piston or the stroke of a bicyclist's leg - into rotary power - the motion needed to drive wheels.

The idea looks simple. Rather than hooking the bottom of a piston rod to a crook in a crankshaft, which is the way piston engines have converted linear motion into rotary motion for 300 years, Raether's model uses a crossbar that runs inside a race in the cylinder wall to twist the piston rod with each stroke. The bottom of the rod spins a gear, which connects directly to a drivetrain, eliminating the crankshaft altogether.

The design of the race gives the piston more leverage throughout its stroke, transferring about three times more of its power than a conventional piston, Raether said.

Among the potential results: Production automobiles that get 75 to 100 miles per gallon, with minimal changes to their standard engines.
(more)
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http://www.sae.org/mags/AEI/SAEWC/8065

Reduced-fuel-consumption engine
13-Apr-2010 16:27 GMT
The WaveTech Engine under development decreases fuel consumption by up to 50% compared to current internal-combustion engines, according to the company's simulations. Factors influencing the claimed fuel efficiency include eliminating the crankshaft; a programmable nontypical piston motion that enables reduced knock, higher compression ratios, and reduced thermodynamic losses; reduced friction because of fewer pistons and mechanical linkages to the driveshaft; and a variable compression ratio allowing for leaner air/fuel ratios and maximum efficiency over a broad rpm range. The engine offers overall package efficiencies compared with traditional ICEs while delivering equivalent or greater power at greatly improved efficiency, the company claims. The WaveTech engine also is said to have fewer moving parts and provide easier maintenance access


NOTE: 50% reduction in fuel conumption translates into doubling of mpg figures. (1/.5 = 2).

[gristy]

1. "... according to simulations."

somebody's looking for a sucker to provide seed money or to sell a patent application to

[JohnWxy]

8. yeah, that's the way it is when you are the first to do something.. there isn't much real world data

recorded of an event that hasn't happened yet.


actually, since the advent of the computer, in every case of a new undertaking, a new design, or a new process simulations have been used (extensively) before committing dollars to the idea. Using simulations is not necessarily a sign of subterfuge. It's actually necessitated by designers, planners and investors wanting to do as much as possible to eliminaate the unknowns in a given undertaking.

[Tesha]

2. How close to the Carnot limit are current gasoline engines?

That will tell you whether any engine can be "three times more efficient"
or not. (They don't exactly claim that, but that's one way to read "transferring
about three times more of its power than a conventional piston".)

Tesha

[joshcryer]

6. Consumer engines, used in cars, are around 20%.

So this is plausible.

[One_Life_To_Give]

13. Wartsila's about 50% or 2/3rds Carnot IIRC

Worlds Biggest Engine - The Wartsila-Sulzer RTA96-C

Facts on the 14 cylinder version:
Total engine weight:
2300 tons (The crankshaft alone weighs 300 tons.)
Length: 89 feet
Height: 44 feet
Maximum power: 108,920 hp at 102 rpm
Maximum torque: 5,608,312 lb/ft at 102rpm

Fuel consumption at maximum power is 0.278 lbs per hp per hour (Brake Specific Fuel Consumption). Fuel consumption at maximum economy is 0.260 lbs/hp/hour. At maximum economy the engine exceeds 50% thermal efficiency. That is, more than 50% of the energy in the fuel in converted to motion.

http://qualityjunkyard.com/2009/05/27/worlds-biggest-engine-the-wartsila-sulzer-rta96-c/

A car engine might run 2-4,000hrs in it's life. That's 3-6 months for one of these power plants. The ROI for purchasing a more efficient engine is much better here than anything we are going to see with out seldom used personal transportation vehicles.

[Statistical]

14. Very cool photos.

Also carnot limit is higher (and more complex to calculate) for diesel which makes it easier to produce high efficiency diesel engines.

[NYC_SKP]

3. So, pistons convert energy into rotational motion at each cylinder, bevel gears to main shaft?:

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings, the engine comprises a block 10 , which is composed of a cylinder block 12 , interchanger block 16 , and crankcase 104 , having bores defined by cylinders 20 , cylinder head 22 , intake means 24 , ignition means 28 , exhaust means 26 , pistons 30 , wave races 70 (upper) and 74 (lower), Interchanger units 60 , rotating carriers 50 , driver and driven gears 82 and 88 , crankshaft 90 , lubrication means 112 and various working and support bearings 52 , 56 and 100 .

In the particularly advantageous embodiment of the invention illustrated, the rotating assembly as shown in FIG. 27, is composed of three main components functioning together, an interchanger unit 60 , as shown in FIGS. 4, 5, and 7 , having track rollers 62 , which ride between two wave shaped races 70 and 74 that are parts of a stationary mounted cylindrical unit as shown in FIG. 23. The third component is a rotating carrier unit 50 , mounted on bearings 52 and 56 , with the top bearing 52 , mounted on a support 54 , that also adds stability to the carrier, as shown in FIG. 11, in which the interchanger 60 rides up and down in to keep the interchanger 60 , centered by means of centering rollers 66 , riding on the carrier tracks 50 c and 50 d as seen in FIGS. 13, 14 and 15 , to maintain correct orientation of the track rollers 62 , on the races 70 and 74 . The carrier 50 , also transfers the converted rotational motion from the interchanger 60 , by means of the power transfer rollers 64 , riding on the carrier tracks 50 a and 50 b as shown in FIGS. 11, 14 and 15 , to the output shaft (crankshaft) 90 , via gears 82 and 88 as shown in FIGS. 1, 11, 13 , 27 and 31 through 38 , Referring to FIGS. 31 through 38, are illustrations of the engine through the four cycles of an Otto cycle or Diesel cycle engine from beginning to end starting with the piston 30 , ready to begin the intake cycle, then continuing through the compression cycle, combustion cycle and ending with the exhaust cycle. In FIGS. 31 through 38 it shows the movement of the track rollers 62 as they traverse up and down the slopes 74 a , 74 b , 74 c , 74 d and 70 a , 70 b , 70 c , 70 c of the wave races 74 and 70 , as also shown in FIGS. 18, 19, 20 and 21 .

The interchanger 60 , is so named because it converts reciprocating motion into rotational motion during the combustion cycle and then converts rotational motion to reciprocating motion during the intake, compression and exhaust cycles. The conversion from reciprocating motion to rotational motion is accomplished during the combustion stroke when the rollers 62 , are forced at the same time down the declining slopes 1 b and 2 b , as shown in FIG. 21, causing a downward spiraling motion. Because the faces of the slopes 2 b , and 2 b are of a 45 degree decline (after a short radius at the top), the downward pressure from the piston 30 , is converted to rotational motion at a one to one ratio. This means that for every inch the piston 30 , moves down, the interchanger will rotate an inch therefore converting the reciprocating motion of the piston 30 , into rotational motion at a 90 degree angle to the axis of the interchanger and therefore achieve an optimal transfer of energy. The rotating carrier as seen in FIG. 12 then transfers the converted rotational motion to the crankshaft 90 , through the driver and driven gears 82 and 88 , when the power transfer rollers 64 , and interchange centering rollers 66 , as seen in FIGS. 6, 7 and 8 , ride up and down the races 50 a , 50 b , 50 c and 50 d , of the carrier 50 , while under the pressure created by the interchanger 60 , as they follow the contours of the races 70 and 74 .

The piston 30 , is returned to the cylinder top (Top dead center) and through the remaining three strokes of the combustion cycle either by centrifugal force from the flywheel 94 , as seen in FIG. 1, attached to the crankshaft 90 , or the power from other pistons connected to the same crankshaft 90 . A flywheel 94 is also used to ensure smooth rotation.



http://www.freepatentsonline.com/y2007/0079791.html

[wtmusic]

5. I may be wrong but

it seems that there may be a wee bit of friction involving the:

centering rollers
carrier bearings
track rollers
power transfer rollers
carrier tracks etc. etc...

which didn't make it to the "simulation"

:silly:

[msongs]

4. internal combustion engines are obsolete, time to let them go and move to something new imo nt

[MineralMan]

7. Yah, well, when they have a working engine installed in a car and they

test it for maybe 20,000 miles, we'll talk again. Until then, it's blue sky and smoke up your leg. Save your money. There are about 20 of these "miraculous" new engine designs floated every year. About zero of them ever see use. Is this the one? Wait for it and see. A year from now, you'll never hear of this project again, I imagine.

[Statistical]

9. The problem with that is you run into carnot limits really quick.

Otto Cycle efficiency limit using gasoline and 10:1 compression is about 60%, and at 14:1 it is about 67%. IIRC 14:1 compression is the highest production vehicle compression ratio for gasoline engine.


(y for gasoline fuel injected engines with optimum fuel air balance is about 1.4)

Most gasoline engines today are roughly 30% efficient. This isn't to be confused with vehicle efficiency. Most internal combustion vehicles have efficiency of 12%-15% (tank to wheel) but that is due to factor beyond just vehicle efficiency.

Here is DOE diagram:


The problem is doubling the mpg rating without changing anything else on the vehicle is in essence doubling the efficiency of the engine. I guess you see where this is going, 2x 30% = 60%. We are getting very close to Carnot limit. However the claim goes beyond that an says 100mpg. That would require doubling some of the most efficient engines in the world (32% - 33%) which is right at carnot limit for 14:1 compression. Now remember Carnot limit is a theoretical engine. One with no friction, no wear, no imperfect parts. An engine achieving those kinds of efficiencies in real world is simply not possible unless you designed some new 0 coefficient of friction surface.

The claim is not credible.

At best it is an exaggeration and the real world efficiencies after you build an engine and have material choice compromises, and handle friction, and put it into a real vehicle with further effieincy losses is much much lower.

At worse it is simply a scam to extract money from investors.
In the 1980s it was the 100 mpg carburetor
http://www.mikebrownsolutions.com/fish3.htm

[JohnWxy]

10. I'm not so quick to totally reject the idea. Even if the potential is over-stated does that mean no

improvement (worth developing) is possible? I am reluctant to totally write something off until it's fully tested.

The obvious concern to me is how much friction is generated in this engine - especially at higher engine speeds. I'm just saying let's not rule out the possiblity that this guy may be onto something.


Here is an observation of a MotorTrend writer on the Wavetech. Now he has a healthy skepticism about this new design which is fine (he calls this a "seriously under-baked engine concept with plenty of areas of immediate concern").

http://motortrend.automotive.com/135437/1004-sae-2010/mubea-springs-wavetech-engine.html


"WaveTech Engines, of Redmond, Oregon believes the key to unlocking the reciprocating piston engine's true potential lies in ditching the crankshaft. In its place, WaveTech proposes a connecting-rod bottom-end fastened to an axle with elaborate wheels that run in a wave shaped trace that runs around the inside of the cylinder bore. The idea is that almost instantly after top-dead-center a typical engine's piston is pressing down hard but generating no leverage and sending all that force right into the crank bearings, whereas a WaveTech piston would already be generating peak leverage and would continue to do so until just immediately before bottom dead center..

Of course, it's those rather abrupt changes of direction at the extremes of the stroke that will concern any mechanical engineer. The inventor, Brad Raether has a number of potential remedies for this, but another issue that strikes me is the greatly increased friction that will come from the piston rotating inside its cylinder. The proof-of concept addresses this by employing a sleeve-valve setup that rotates with the piston, but the cooling and lubrication implications of that "fix" seem worse than the problem. We'll keep an eye on this concept too, though, because you just never know where the Next Big Thing may come from.
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Here is something interesting on this engine from the SAE Vehicle Engineering online:


http://www.sae.org/mags/sve/power/8080

WaveTech increases compression ratios and lowers heat in the cylinder, improving the fuel ratios while reducing emissions. It uses a double-helical cam to convert linear motion to rotating power. The 75-lb (34-kg) reciprocating-piston engine provides the output of a 6.2-L engine. The prototype uses an opposing piston configuration.

[Statistical]

11. Yeah if they can get investors they should go for it.

I think likely it is more in the category of over estimating.

Not quiet "lying" but being fast and loose with facts. You know simulation discounts friction loses. The "miles per gallon" are for engine only which vastly overstate what is accomplished when placed inside an actual vehicle.

That sort of stuff. Still if we could get ICE that is 30% more efficient and cost effective that would be great. Even with rapid replacement of ICE with alternatives (say 2 million vehicles a year in US) it will be decades before ICE is completely gone.

[madokie]

12. This design uses a wedge to transmit the power from the burning of the fuel

rather than a lever as a conventional engine does and therein lies the reason this will be a more powerful engine, all thing considered. by using a wedge, as the spiral is, the power transmitted is the same the whole stroke whereas when using a lever in a rotating manner as the crankshaft is the mechanical advantage is at its most only during the mid stroke of the power piston. Very little mechanical advantage to a lever/crankshaft at the top of the pistons stroke where the most energy is and at the bottom of the stroke where there is still a sufficient amount of energy to be harnessed. I can see how this will improve on the conventional engine and to the point to where it would be worthwhile. Thanks for the link and info John.

edit: you can only recommend a post within the 24 hour period as I just found out. In other words I tried to rec this but couldn't.
peace