Posted on 08/14/2016 9:50:59 PM PDT by 2ndDivisionVet
ATSUGI, JAPAN -- Japanese automaker Nissan Motor Co has come up with a new type of gasoline engine it says may make some of today's advanced diesel engines obsolete.
The new engine uses variable compression technology, which Nissan engineers say allows it at any given moment to choose an optimal compression ratio for combustion - a key factor in the trade-off between power and efficiency in all gasoline-fuelled engines.
The technology gives the new engine the performance of turbo-charged gasoline engines while matching the power and fuel economy of today's diesel and hybrid powertrains - a level of performance and efficiency the conventional gasoline engine has so far struggled to achieve....
(Excerpt) Read more at reuters.com ...
Sounds good
So many promises, yet so little delivered.
Well VW certainly is doing its best!
Better Article:
http://www.autoblog.com/2016/08/14/infiniti-vc-t-engine-variable-compression-official/
VW caved too easily, due to WWII guilt.
Should have fought it in court about 15 years.
Cars would be worn out by then.
Then what difference would it make.
First continuously variable transmission, now continuously variable compression...
“Advanced diesel engines of today” they are talking about are the tiny car engines that have been smoking the gas guzzlers in performance in cars that weigh next to nothing.
Diesel fuel has more energy per gallon than gasoline so a gas fueled engine of the same design cannot out perform its diesel powered counterpart. Give me a diesel engine with the same type of research and technology that went into this gas burner and you will have the winner.
Diesel is where the POWER is! No mention of ft-lbs of torque required to move a multi-ton load across the contenent.
The army developed a variable compression dual fuel engine for trucks and it was a mechanical disaster.
Actually, I would go with “the promised fuel economy is at roughly the lower bounds of diesel fuel economy” as a criticism.
No surprise since a 14:1 compression ratio, the upper limit of the varialble compression scheme described, is also about the lower limit of diesel compression ratios.
This should translate into a peak efficiency somewhere around 14-16 HP per gallon of fuel burned per hour given that gasoline engines seem to top out around 13 HP per gallon per hour, with 10 or 11 being more typical.
Diesels by comparison, with compression ratios running to about 20:1 in a few engines, can make up 20 HP per gallon per hour.
I’m not making light of peak efficiency of up to 14-16 HP per gallon per hour from gas, mind you.
“No mention of ft-lbs of torque required to move a multi-ton load across the contenent.”
Are you referring to truck or train?
Geez, that diagram in the article screams of mechanical over complication of a much easier solution considering today’s availability of technology.
I had worked on an engine a guy developed that used one valve per cylinder. Could run any fuel and its valves were controlled by a solenoid whose actuation was not off and on but of a variable drive and not connected mechanically to a camshaft. All the camshaft was used for was pulse timing for sensors. This thing could do the Cadillac 4-6-8 thing based on torque demand coupled to speed and it had the capability to have those cylinders not compress at all if they were determined to be “off” by the injection and ignition computer. Of course I am leaving something out.
No fuel delivery and no compression meant less power loss and fuel savings, as designed for highway cruising and lots of power for stump pulling.
Complicated electronics but only in the software to manage the whole thing.
Diesel is power, and if I am not mistaken, a barrel of crude cannot be turned into a barrel of gasoline without massive waste. There’s a role for gasoline and diesel and even the electrics and cng. No one size fits all.
Are these new engines going to require more mechanical parts as well as electronics to run them?
If so today’s Diesel engines would be much more dependable.Thats why the military depends on Diesal engines on its equipment.its easier to maintain.
I think it would be wise to wait 2-3 years to see if they have the bugs worked out.
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