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Mazda Motor Corp said it would become the world's first automaker to commercialize a much more efficient petrol engine using technology that deep-pocketed rivals have been trying to engineer for decades, a twist in an industry increasingly going electric.
The new compression ignition engine is 20 percent to 30 percent more fuel efficient than the Japanese automaker's current engines and uses a technology that has eluded the likes of Daimler AG and General Motors Co.
Mazda, with a research and development (R&D) budget a fraction of those of major peers, said it plans to sell cars with the new engine from 2019.
"It's a major breakthrough," said Ryoji Miyashita, chairman of automotive engineering company AEMSS Inc.
[...] A homogeneous charge compression ignition (HCCI) engine ignites petrol through compression, eliminating spark plugs. Its fuel economy potentially matches that of a diesel engine without high emissions of nitrogen oxides or sooty particulates.
[...] AEMSS' Miyashita said a key issue would be how smooth and responsive the engine is.
"Is it jerky? If so, that would pose a big question when it comes to commercializing this technology." he said. "Hopefully Mazda has an answer to that question."
Source: http://www.reuters.com/article/us-mazda-strategy-idUSKBN1AO0E7
(Score: 0) by Anonymous Coward on Wednesday August 09 2017, @11:19PM (5 children)
> A homogeneous charge compression ignition (HCCI) engine ignites petrol through compression, eliminating spark plugs.
I believe that one trick that makes this difficult is that the engine switches back and forth between spark or other assisted ignition and pure compression ignition. The other is that gasoline explodes (knocks) violently compared to slow burning diesel fuel, so the engine has to control and quiet this, likely by staged fuel injection (many little squirts, not one big dump of fuel each power stroke).
Anyone have any experience or the time to look for references?
(Score: 3, Interesting) by LoRdTAW on Wednesday August 09 2017, @11:40PM
See my comment below, link: https://soylentnews.org/comments.pl?noupdate=1&sid=20991&page=1&cid=551347#commentwrap [soylentnews.org]
None of this sounds hard at all. Diesel engines have been using pulsed injection for a while for emission control and quieter/smoother operation. If they kept the spark plugs they would have to ensure they can take that kind of pressure. But if you are running compression ignition and direct injection, why even bother with the plugs? My only thought is there might be starting issues or low speed operation and dealing with the possibly higher compression ratios for the autoignition of petrol. Might need to start and warm up using spark plugs and then switch to diesel cycle. None of this sounds like a major breakthrough. But marketing likes to think so.
There was an old International bulldozer from the 40's, the TD 6, that used a hybrid gas and diesel engine to overcome starting issues. You started it on gas and then pulled a lever to switch to diesel after the engine fired up on gas (youtube has a bunch of TD 6 videos).
(Score: 2) by richtopia on Wednesday August 09 2017, @11:54PM (3 children)
Here is the wikipedia article: https://en.wikipedia.org/wiki/Homogeneous_charge_compression_ignition [wikipedia.org]
You are correct, the major issue has been controlling the autoignition. I'm not sure how Mazda solved it, I think the previous leading method is variable compression which is also a difficult technology to achieve.
(Score: 1, Interesting) by Anonymous Coward on Thursday August 10 2017, @12:30AM
Has been at least partially solved for some time (2014) using machine learning to predict the chaotic behavior of HCCI:
https://www.youtube.com/watch?v=_yrLWFffP_Q&t=570s [youtube.com]
(Score: 2) by Grishnakh on Thursday August 10 2017, @01:20AM (1 child)
Variable compression isn't hard at all today, thanks to Atkinson-cycle engines and variable-valve timing. Mazda's newest engines already employ this technology (basically, holding the exhaust valves open a bit longer when in Atkinson cycle, IIRC; the engines switch to Otto cycle at full throttle I believe).
(Score: 0) by Anonymous Coward on Thursday August 10 2017, @04:09AM
You realize there's a difference between "hard to accomplish" and "hard to manufacture" right? Try making it as CHEAP and RELIABLE as current models. Now you've got a breakthrough.
Damn near everything "new" takes 10-20 years before it hits the market. We've had prototype quantum computers. Prototype transistors that run at 100 GHZ. But can those transisters be made cheap enough and in high enough densities? Not yet.