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-   -   This is SO NEW.. why did we not think of this? (http://www.peachparts.com/shopforum/diesel-discussion/391175-so-new-why-did-we-not-think.html)

leathermang 01-25-2018 10:18 PM

This is SO NEW.. why did we not think of this?
 
compression ignition..

https://www.yahoo.com/finance/m/06628167-f04d-305e-85a1-a2b95555ab37/ss_compression-ignition-engines.html

NZScott 01-25-2018 10:27 PM

Do I detect some sarcasm here...the headline should have the important words Homogenous Charge in front of compression ignition, vastly different from our engines

NZScott 01-25-2018 10:29 PM

Model "diesel" engines (which don't run on diesel nor have a fuel injection system) are HCCI.

tjts1 01-25-2018 10:43 PM

Quote:

Originally Posted by NZScott (Post 3783464)
Do I detect some sarcasm here...the headline should have the important words Homogenous Charge in front of compression ignition, vastly different from our engines

Except the Mazda engine is not HCI and it still uses a spark plug at every combustion even but they somehow still claim that it's compression ignition. There's other articles that explain this in more detail.

Diseasel300 01-25-2018 10:48 PM

I remember reading an article in a magazine (I think it was Popular Mechanics) back in the 90s regarding the development of compression-ignition petrol engines. The problem then (and I assume still applies now) was the generation of NOx due to the lean burn. Diesels are being slammed for their NOx production, the original Honda Insight with it's lean-burn engine was killed off due to NOx production, and I see nothing mentioned in the article how they're dealing with NOx...

NZScott 01-26-2018 03:42 AM

Quote:

Originally Posted by tjts1 (Post 3783471)
Except the Mazda engine is not HCI and it still uses a spark plug at every combustion even but they somehow still claim that it's compression ignition. There's other articles that explain this in more detail.

I read it properly and you're quite right. Previous articles I had read didn't mention that bit...

So to me they're basically running it lean and using a controlled form of detonation (spark ignites the fuel partly and causes a pressure and heat spike to ignite the rest of the charge?) wonder how strong the internals are. Not as strong as a real diesel I'd imagine.

oldsinner111 01-26-2018 06:40 AM

I wonder,this gasoline does not lubricate like diesel, so I don't expect million mile motors.

dieselmania 01-26-2018 08:52 AM

Quote:

Originally Posted by Diseasel300 (Post 3783473)
I remember reading an article in a magazine (I think it was Popular Mechanics) back in the 90s regarding the development of compression-ignition petrol engines. The problem then (and I assume still applies now) was the generation of NOx due to the lean burn. Diesels are being slammed for their NOx production, the original Honda Insight with it's lean-burn engine was killed off due to NOx production, and I see nothing mentioned in the article how they're dealing with NOx...

They actually do mention it, claiming that lower combustion temps will reduce NOX output. My very basic understanding of NOX is that lower temps in general reduce it's output, but I am far from an expert on the subject.

97 SL320 01-26-2018 06:36 PM

Quote:

Originally Posted by oldsinner111 (Post 3783515)
I wonder,this gasoline does not lubricate like diesel, so I don't expect million mile motors.

With modern gasoline fuel control , better piston ring sealing and oils, there is far less fuel contamination of oil than in days past. Since oil in a gasoline engine stays cleaner much longer, any advantage a diesel had is long gone.

And remember, a diesel " car " isn't any different than a gasoline " car " so don't expect the " car " portion to last any longer just because it is a diesel.

Father Of Giants 01-26-2018 08:48 PM

This reminds me how formula 1 cars are starting to use pre chambers in their engines in order to run an air fuel mixture that is as lean as possible.

As the price for fuel goes up, lean air fuel mixes for gasoline cars will soon be king of the road, since they are very efficient. Then again, I'd imagine the cost of producing such engines to be more expensive than the regular gasser...

Dubyagee 01-26-2018 09:15 PM

The Honda CVCC (Compound Vortex Controlled Combustion) ran pre chambers and an extra intake valve to inlet a fuel rich mixture as needed. A friend had one and I dont ever remember him at a gas station with it. I had a 1972 Newport and was at the gas station quite a bit.

leathermang 01-26-2018 10:38 PM

I had an old ALL CAST IRON Briggs and Stratton engine which was used on a David Bradley walking tractor which used a prechamber....it was a gas engine....Even the Flywheel with fins was cast iron...

97 SL320 01-27-2018 10:00 AM

Quote:

Originally Posted by Dubyagee (Post 3783740)
The Honda CVCC (Compound Vortex Controlled Combustion) ran pre chambers and an extra intake valve to inlet a fuel rich mixture as needed.


Some 80's Mitsubishi 4 cylinders ( also found in Chrysler products ) used the same process called MCA Jet. It is far easier to light off a rich mixture than a lean one. On the Mitsu it really isn't a pre chamber, it is a nozzle that directs a small amount of a rich mixture towards the spark plug that is in the standard location.

Diseasel300 01-27-2018 10:43 AM

Quote:

Originally Posted by dieselmania (Post 3783533)
They actually do mention it, claiming that lower combustion temps will reduce NOX output. My very basic understanding of NOX is that lower temps in general reduce it's output, but I am far from an expert on the subject.

That's all well and good at cruising speed when the fuel consumption is low, but what about when the engine is under load? Accelerating, climbing a grade, passing someone, towing? The engine MUST run richer at those periods and that's when the NOx production goes up significantly in a lean-burn condition. I have to wonder if these new engines are going to be using massive amounts of EGR with a cooler like the modern diesel truck engines do to meet emissions standards...

Father Of Giants 01-27-2018 05:13 PM

So did the Honda cvcc run a rich fuel mixture in the prechambers, while the combustion chamber was extremely lean? Causing the spark from within the prechamber to ignite the cylinder? Funny how such "groundbreaking" technology has been around for ages, it's just that now we're able to hone in these combustion processes at very precise levels. Nobody is reinventing the wheel, just making sure it can roll a little bit better...

I've also read articles that stated cost of emission control devices will go up if these powerplants are implemented in mass.


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