when I first read the first post on this page it sounded almost excactly like the CVCC engine that honda made starting in the late 70's, and sold up untill 1987 when they switched from carburated to fuel injected, and as much as I like fuel injection, the cvcc head design was amazing, and simple, it would just require two fuel injection systems, or a fuel injection and carburation set up.
Stratified Charge engines have been around for a long time - this was the technology that produced our beloved Civic. The real name of the Civic, or CVCC is the "stratified charge, compound vortex controlled combustion" - they got the stratified charge part down pat, but the compound vortex part was hard to get. Calling it the SCCVCC would just sound bad, so they dropped the SC and called it the CVCC, even though it was more stratified charge than compound vortex.
Yes, the CVCC was a stratified charge engine. My dad had one for a short time, danged thing had a carb and got 60MPG, and while it wasn't the fastest thing I ever drove it got itself down the road pretty good. Honda's based pretty much all their engines off the same technology, updating it as they went. This is why they can get an average of 30 percent better fuel efficiency than a domestic at the same power levels, and why most of their engines meet the ULEV standards.
What I want to see is not a hybrid, but an actual diesel electric vehicle like a train where the engine is completely disconnected from the drivetrain, like a locomotive. They could probably use this to put a 1 liter diesel engine into a full size car, drive it at normal highway speeds with normal accelleration, and see 60-70MPG out of it, if not more. A locomotive is able to move thousands of tons of materials cross country more efficiently than a semi can, so obviously the power is there. Scaling it down to a car size shouldn't be that hard. Found a web site that stated a diesel electric train normally uses 1.5 gallons per mile, but as we all know that 1.5 gallons per mile is moving about 300 semi tractor loads worth of goods. This means that those semis would have to all be getting about 200 miles per gallon to match that train.
Interesting. I assume they use heavily spring-loaded cylinders (AKA a hydraulic accumulator) to store energy? Such a system would make sense if they were using a hydraulic transmission... A pump attached to the engine and hyraulic motors on each wheel, as commonly found on industrial equipment. Otherwise, it seems like they could have chosen a less complex spring energy-storage system.
If they're comparing it to NiMH batteries, they must have managed a pretty respectable energy capacity, which either means lots of fluid volume, or ridiculously high pressures.
Then again, they only seem to be talking about the energy storage efficiency - the energy the system releases compared to what was used to charge it. In that case, it might have a relatively small storage capacity, and they're just trying to talk their way around that imperfection.
Even if it only has enough energy storage capacity to accelerate away from a light or two, it could still be a significant help FE-wise with city type stop-and-go conditions, preticularly with such a heavy vehicle. If it's as efficient as they say, alot of the kinetic energy of the moving vehicle could be reclaimed during braking and re-used to accelerate. Unlike a battery, there would be almost no limitation on charge rate, and running it down to zero would have little effect on it's longevity.
On the other hand, so little capacity would probably be useless in steady-state driving like on the highway. I guess they could conceiveably use it as a sort of automatic pulse and glide system... The engine starts up, drives the wheels and fully charges the hydraulic storage, then shuts off and lets the storage keep the vehicle moving. Once the storage is nearly drained, the engine starts up again. Done properly, there would be no noticable change in vehicle speed or acceleration, but the engine constantly cycling on and off might be distracting for the average driver.
Unfortunately they didn't go into the details, which I wouldn't either if I were looking at a system that would allow me to sell highly profitable SUVs that blow the competition away on mileage. That even beats out small cars like the Civic and Corolla. If they could fit the system to a small car, it might see 150MPG+. And I'm talking how normal sheeple drive, not how folks here who hypermile do.
Peterbilt and Eaton Corporation are jointly developing refuse trucks using Eaton’s parallel hydraulic hybrid system—Hydraulic Launch Assist (HLA). Peterbilt plans to build and evaluate a production version of the vehicle during the next year.
Eaton Corporation has received a $2.15 million contract from IMPACT Engineering Inc. to accelerate commercial development of Eaton’s hydraulic hybrid system (Hydraulic Launch Assist—earlier post) for a US Army program.
The US EPA and its industry partners today unveiled the world’s first diesel-hydraulic series-hybrid delivery truck. (Earlier post.) The hydraulic hybrid offers an improvement in fuel economy of up to 60-70% and a reduction in CO2 emissions of 40% or more compared to a conventional diesel-powered truck.
The CVT transmission is also mentioned. It's definitely a system that targets city stop-and-go traffic.
Found out more about it. The system apparently uses a large cylinder like an oxy-acetaline torch would use with a bladder inside. The bladder is pressurized to about 5000PSI. A regenerative braking system is used to fill the bladder with hydraulic fluid, and that is used to help launch the vehicle when you take off again.
If this is how it works, I'm impressed that they can use hydraulic pressure to get a vehicle moving, but that's about it. I don't see how they are going to be able to get enough pressure into the system during a braking maneuver to get the vehicle moving again, nor do I see how this will actually make a full size SUV or truck get 60MPG.
Like the pressure tank that people with their own water wells have, huh? But rated for >5000 psi... Well, maybe they can make it work. They have been "on the verge" of putting it into production for 8 years now, that I know of.