Posted on 04/17/2007 10:05:49 AM PDT by Red Badger
An earlier rendering of the VCR mechanism.
FEV Engine Technology is displaying a developmental gasoline/E85 turbocharged direct injection (GTDI) engine that also features variable compression ratio (VCR) at the 2007 SAE World Congress.
The engine is being developed in-house, in tandem with several other DI engine projects that FEV is working on with various automakers, based on earlier work FEV had done with the VCR platform. While offering the potential to generate V-8 power from a V-6 engine, this concept also provides roughly a 20-25% improvement in fuel consumption.
The VCR system is based upon the concept of an eccentric crankshaft bearing. Rotation of the eccentric bearing leads to a vertical position change of the crank train relative to the cylinder head and thus, a continuous change in the compression ratio. An electric motor controls the adjustment between compression ratios of 8 and 16. FEV has deployed a VCR engine in a demonstration vehicle, and is further optimizing the adjustment mechanism. There is interest in the OEM community in the work, according to Dr.-Ing. Joachim Wolschendorf, Vice President Engineering and Chief Technical Officer.
The VCR element allows the engine to take advantage of the higher octane of ethanol by increasing the compression ratio for higher-level ethanol blends. FEV is currently working to optimize a control strategy for engine management that will take into account the compression ratio as well as load and the fuel mixture.
Although the three principal elements of the engine—VCR, GTDI and Turbocharging—have been tested on the bench and on the road, FEV has not yet put all three together in a vehicle.
Rest In Peace, old friend, your work is finished.......
If you want on or off the DIESEL "KnOcK" LIST just FReepmail me........
This is a fairly HIGH VOLUME ping list on some days......
Ping! & KnOcK!......
I wonder if it will be available in the United States. Right now you can buy ethanol, just not the vehicle which is optimized for ethanol...but you can buy that vehicle in Europe and one is even made by an American auto manufacturer.
cylinders, cylinder heads, valves? Your engine looks a little light.
It’s a cutaway profile to show the rotatable crankshaft, mounted on an eccentric bearing that can be shifted via computer control.........
With a VCR system, it might be made able to run on Gasoline OR Diesel as necessary!............
I wonder how many engines they've melted developing this contraption. They are kinda getting away from the KISS system(keep it simple, stupid) engineers are supposed to try stick to. Adding more parts isn't the best thing to do.
eccentric crankshaft bearing
cool enough as a concept, but just count all the other devices that need to adjust to a new crank centerline, and start with just the front and rear shaft seals (oblong will never do)......such a system would require so many servo’s that they alone would complicate engine real-estate off the scale......
Simply rotating the crankshaft on the eccentric doesn’t seem to add a whole bunch more parts. It looks really simple........
It’s be known as the motor with the wobbly crankshaft, that feels like the tranny is going to come through the floorboards as that crank its bolted to moves up and down.
Imagine what a broken tranny mount would feel like with that setup!
GM should build these, so they’ll be reliable. Remember how well engineered the Vega engine was? Remember the late 70s diesels?
“Rotation of the eccentric bearing leads to a vertical position change of the crank train relative to the cylinder head”
Hehehe
I wonder how many of those suckers were launched into low earth orbit during testing. One would not have to disassemble the engine to see how cleanly the fuel burn was.....just take a peek through the side of the engine block.
hmmmm, why not try a Sterling engine?
LoL! just thinking of the engineering nightmare this concept has will give me nightmares for a while. Oh well, they have tons of R=D money to spend, and lots of room in the “stupid idea’s we’ve tried” graveyard. I’ve seen that place a few times. There’s some amazing junk piled up in there.
LoL! just thinking of the engineering nightmare this concept has will give me nightmares for a while. Oh well, they have tons of R+D money to spend, and lots of room in the “stupid idea’s we’ve tried” graveyard. I’ve seen that place a few times. There’s some amazing junk piled up in there.
I think I'd opt for hydraulic drive with that setup. Direct drive the pump, and let the hydralulic lines take care of the vertical crank motion.
I have to wonder what kind of problems there may be keeping the mains lubed. Looks like a lot of potential for oil leakage/pressure loss in that carrier setup.
I dunno — I switched to DVD and I’m happy there.
The outside of the bearing remains circular, it’s the center that moves. Granted, I have no idea how they couple the power to the tranny........
Help a novice here; what’s the purpose of variable compression ratio if the engine is turbocharged anyway?
Could you please add me to your ping list, Thanks.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.