Sandman

I saw Syrob's thread about Direct Injection and thought that you might be interested in HCCI: Homeogeneous Charge Compression Ignition.

HCCI is an engine technology under development that can improve fuel efficiency and power by up to 50% over conventional Spark Ignition/Otto Cycle Engines. Within 5-10 years HCCI could be a practical reality with thermodynamic efficiencies approaching that of a Diesel Ignition engine with almost no NOx or soot! HCCI runs on a very lean fuel air mixture and ignition is not by a spark plug but by compression auto-ignition. The pressure in the cylinder created by the moving piston almost perfectly ignites the fuel/air mixture with very litte combustion byproducts.

It is more of an engine technology than an engine itself. HCCI technology can be combined with gasoline engines or diesel engines. There are dozens of ideas about how to use this technology - and some of them are a "hybrid" approach, for example one proposal would have an engine running a standard spark-ignition cycle until the engine got above a certain RPM and then switch into a HCCI cycle.

A big challenge with HCCI is in controlling when this auto-ignition happens. But there are lots of potential ways of handling this and researchers are working on ways to solve this problem.

The really neat thing is that there is a lot of experimentation going on with engine technology. The gas engine is far from dead! And hopefully we will continue to see big leaps in power and efficiency. This way we can enjoy our future Lexus vehicles without having to worry about oil shortages and destroying the environment. Can you imagine the 2.0L engine that delivers 350HP and gets 75MPG - and produces almost no emissions?

Links:

http://www.tfd.chalmers.se/~ogink/index.html (see sidebar links)

http://www.greencarcongress.com/2004...n_eye_on_.html

http://www-cdr.stanford.edu/dynamic/..._7_21_2003.pdf (Not for those with a weak stomach)

Sandman

Since this thread is about new and potentially useful engine technology I'll also mention that a lot of research is being done to eliminate mechanical valves and replace them with electro-mechanical valves. Ideally you would have an electromechanical device (such as a solenoid or an electric "shutter") that you could have a microprocessor control to open and close. Today we have large, heavy valves that cause friction and drag and can only be controlled within the limits of VVT-i. The only limitations to electro-mechanical valves are how responsive the valves are to the electric commands and how creative your firmware programmer is. Bye-bye valves (valve tap), cam shaft, timing chain/belt, etc!

A big part of combustion is how the engine breathes. We have seen the benefit to controlling the exhaust valves in the new GS V6 - it can help widen the torque curve. Having electro-mechanical valves controlled by the engine micro would be a big step forward in performance and efficiency.

An obstacle to this technology is inexpensive processing power. The processing power required to emulate what a CAM does is still cost prohibitive, but not for long.

Sandman

One other technology that is interesting is SHEP - Stored Hydraulic Energy Propulsion.

There are a few companies perfecting this new technology. One is UK based SHEP Technologies, Inc. (recently acquired by a Canadian Holding Company), and another is Permo-Drive Technologies from Australia. The system works a lot like the electric hybrid cars that Lexus is making except that instead of generating electric charge and storing it in a battery, SHEP recovers energy during deceleration and braking and converts it into stored hydraulic energy. Instead of a battery it uses an "accumulator" which stores a highly compressed nitrogen gas. This energy can be called up on demand and supplied back to the wheels through a hydraulic motor. The manufacturers claim that they can cut fuel consumption in half for city driving and can increase torque (and therefore horsepower) by about 40-50%. It also saves tremendously on brakes - since most of normal braking can be achieved through the use of SHEP.

The cost to convert a large SUV to SHEP is only around $600 which is significantly less than that of an electric hybrid.

SHEP claims to be working with "one of the world's largest car manufacturers" on extensive testing of this technology. My research shows that this is Ford - but I'm not certain. Deployment in an automobile in the near future is likely, but the technology is also well suited to buses, delivery trucks, garbage trucks etc, that do a lot of stopping and starting.

Links:

http://www.shepinc.com/

http://www.permo-drive.com/

http://www.iags.org/n033104t3.htm

http://www.greencarcongress.com/2004...and_peter.html

XeroK00L

Very interesting, mind-blowing technologies, Sandman!
Thanks for sharing the research.

The SEHP seems to be a more approachable technology in the near term than HCCI, but both will be able to work hand-in-hand.

Hopefully Toyota will be able to make enough money with their HSD technology before those new technologies matures. The SEHP in particular seems to promise HSD's benefits without the complexities that come with it.

The future of the automotive industry has never looked brighter.

BTW, shouldn't this be better posted in Car Chat instead of the 3GS forum?

Sandman

I'm glad you liked it, XeroKOOL. I just love this new technology. I love the challenge of going beyond what everyone says is possible. I'm hoping that 30 years from now the cars we are driving will be what we now think of horse and carriages.

Well, I was inspired by the post that Syrob did on Direct Injection. Maybe I should have just dropped these 3 under his thread. I don't look on the other sections of CL - I'm only interested in the Gen 3 GS section - so it didn't occur to me but you are probably right. I doubt that this will get a lot of exchange so it probably doesn't matter either way. Let's see what the Admin's want to do....

adale

Just to add a little more....several auto manuf. are toying with the electro-mechanical valve idea. As was stated earlier, they are have processing issues another and to some degree bigger problem is heat managment. The valves in our cars get really hot and if you are using a coil to actuate them then the coil gets hot and you know where it goes from there. Another approach is using air pressure to accuate the valves. All F1 teams do this in their motors for several reasons starting with speed of valve movement. This is how the F1 motors get to 19,000 + RPM. The problem there is air delivery and storage, as these cars have tanks and do not generate their own air pressure. None of the teams tell the exact pressure these systems operate at, but needless to say, it is very high. Because BMW uses this technology, they do not use a normal fuel injection "butterfly" type throttle body, but instead they make the valves do the TB work. This technology is slowly coming off the race track and into our daily drivers and I like it!!!! I realize that F1 motors are hand assembled and built to only last a few hours, but still, while they are alive they are living life and the bleeding edge. What a age we live in?

Rockville

Thanks Sandman. We live in interesting times. We are witnessing a paradigm shift in the Auto at this time. 2006 is the dividing line of the new wave of engine technology and electric motor use.

SYROB

Great stuff guys !

SYROB