Mazda Skyactive Engines

[kingjr9000]

Mazda plans big efficiency gains
Petrol engines fitted to Mazdas in five years’ time will be significantly more fuel efficient than today’s

Mazda is aiming to lift the efficiency of its petrol engines by 50% by 2020, according to European research and development chief Kenichiro Saruwatari.

The current efficiency of its petrol engines is a competitive 40%, but it hopes to reach 60% in the next five years.

It hopes to do this by developing its homogeneous charge compression ignition technology (HCCI), in which the mixture is ignited by compression rather than a spark, like a diesel.

That will involve raising the compression ratio from about 14.0:1 today to 18.0:1 and achieving very precise control of the combustion process to avoid knock. The aim is to combine the cleaner emissions of a petrol engine with the efficiency of a diesel.

As part of its Skyactiv efficiency programme, Mazda is also investigating scope for reducing heat lost through the exhaust system, which typically loses about 30% of the fuel’s energy. “We’re looking at several solutions but can’t say which yet,” said Saruwatari.

The company has been pursuing its current efficiency path since the development of the 2002 Mazda 6, which was “generation one of the roadmap”, Saruwatari said.He said the next CX-5 crossoverwill be the first of the seventh generation. “The main direction of Skyactiv has not changed,” he added, “although we sometimes find new technologies and materials that produce a step change.”

Mazda recently announced a partnership with Toyota that could result in a plug-in hybrid model, but it has said its petrol cars could ultimately match EVs for well-to-wheel efficiency. This could mean average well-to-wheel CO2 emissions of about 80g/km for an unspecified ‘average’ model equipped with a Skyactiv Generation 2 engine.

The third generation of Skyactiv engines could take this even further. Mazda has previously spoken of average well-to-wheel emissions as low as 50g/km, although it has not set a date for this.

 

[kingjr9000]

Yes. I know this is old information, but i was just wondering if its actually possible. Does anyone on here know?

 

[Karabiner98k]

Skyactiv technology has not been as successful as Mazda's claims. The real world fuel consumption tests done by magazines show that there are more efficient and faster cars than Skyactiv-Equipped Mazdas.

Mazda once said that they don't believe in Turbo engines and they insisted on producing their 2.0 & 2.5 N/A engines. But soon they found that those engines doesn't have enough torque to satisfy customers and they had to produce a Turbo version of Skyactiv 2.5 which fitted to the new CX-9. But unfortunately, CX-9 2.5 Turbo is still thirstier and slower than some of it's European rivals (like X3 28i).

http://www.caranddriver.com/mazda/cx-9
http://www.caranddriver.com/reviews/2013-bmw-x3-xdrive28i-test-review

The other complaint is about rough idle and noisy operation of Skyactiv petrol engines. But Skyactiv diesel engines are known to be fast and refined although not again at the same level of European rivals.

It is easier said than done! There is a gap between theory and practice.

 

[bum-man]

They are not in the same category. The CX-9 is a 7-passenger SUV of course it will be slower and thirstier. Higher curb weight, larger body, more torque, and crappy transmission (relatively).

 

[Karabiner98k]

Even X5 35i which is both heavier (272 kg more!) and insanely faster than the Mazda, is more fuel-efficient!


http://www.caranddriver.com/reviews/2014-bmw-x5-xdrive35i-test-review

 

[kingjr9000]

Mazda to Launch Skyactiv-X Engine with Compression Ignition in 2019

AUGUST 8, 2017 AT 3:48 PM BY TONY MARKOVICH

Mazda may be dipping into the past with its new factory effort to restore first-generation Miatas, but the company otherwise has its sights set on the future. Mazda announced that it is expanding its environmental initiative by setting new efficiency, safety, and sustainability goals for the coming decades. The most significant development is a new generation of engines, dubbed Skyactiv-X, set to launch in 2019. Mazda claims it will be the first commercial gasoline engine to use compression ignition technology.

Known officially as Homogeneous Charge Compression Ignition (HCCI), the technology is something many auto manufacturers have been working on for years. However, issues with narrow powerbands (read: unusable for normal customers) and managing emissions have held up mass-scale implementation. An HCCI engine pressurizes an air-and-fuel mixture until the generated heat detonates it. It is controlled detonation, a condition to be avoided at all costs in normal gasoline engines.

Unlike a diesel, which only always relies on compression ignition, an HCCI engine still employs a spark plug during maximum load, or high power, situations. Basically, Mazda will have the best of both worlds: an engine with the cruising efficiency of a diesel without sacrificing a peppy top end.

The company did not specify which models would get the technology, but it did say that the Skyactiv-X engine will be supercharged to increase power and improve response. Torque output with the new tech also is claimed to be 10 to 30 percent better than that in the current Skyactiv-G models.

The proprietary method is called Spark Controlled Compression Ignition, and Mazda claims it improves efficiency by 20 to 30 percent from its current Skyactiv-G engines. The efficiency and torque gains allow for “much more latitude in the selection of gear ratios.”

The HCCI news comes shortly after the company announced a partnership with Toyota, working on EV technology. Mazda’s overall goal is to cut carbon dioxide emissions in half by 2030, from their 2010 levels. Expect more details on Skyactiv-X later this year.

From C&D

 

[kingjr9000]

Electrification arrives same year
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• Mazda has revealed that it will introduce a new gas engine that uses compression ignition as part of its long-term tech development dubbed “Sustainable Zoom-Zoom 2030.” Called Skyactiv-X, the new mill will be the world’s first compression-ignition gas engine to go into mass production, according to Mazda. The automaker says that it intends to prioritize efficiency improvements for the internal combustion engine since Mazda believes it will power the majority of cars for some time. Mazda will also combine its super-efficient engines with electrification starting in 2019, the same year that the new Skyactiv-X engine will arrive. Part of the new plan also aims to reduce the company’s carbon dioxide emissions in 2030 by 50 percent compared to 2010, and 90 percent by 2050.
  
  The engine features a proprietary combustion method that Mazda calls Spark Controlled Compression Ignition, which it says solves the two issues that originally kept it from getting commercialized: maximizing the zone where compression ignition can happen and making the transition between compression and spark ignition as seamless as possible, combining the advantages of gas and diesel engines to improve fuel economy and performance. In this way, Skyactiv-X differs from Homogeneous-Charge Compression Ignition (HCCI) designs, which don’t use spark plugs. In addition to compression ignition, Mazda also adds a supercharger to improve fuel economy and engine response, and increase torque between 10-30 percent over the current Skyactiv-G engines found in current Mazda vehicles. Compression ignition also enables a super lean burn, improving the Skyactiv-X engine’s efficiency by 20-30 percent over the current Skyactiv-G powertrains and 35-45 percent better than the MZR units from 2008.
  
  
  In addition to the new engine, Mazda has also announced that it will begin electrifying its cars in 2019 but focus on markets it calls “regions that use a high ratio of clean energy for power generation or restrict certain vehicles to reduce air pollution” (read: markets with extremely strict emissions standards). This comes right after the automaker signed a joint venture with Toyota, which will see both automakers share a new factory in the U.S., and co-develop electric cars, connected-car systems, and new safety tech.
  
  Autonomous driving tech is also part of the Sustainable Zoom-Zoom 2030 initiative and it will see Mazda begin its Co-Pilot Concept in 2020 and it plans to make it standard on all of its vehicles by 2025. Additionally, it will make its i-ActiveSense suite of active safety features standard on its vehicles. In its home market of Japan, Mazda has already started to make features such as automatic emergency braking standard on some of its vehicles. U.S.-market vehicles such as the 2017 Mazda CX-5 and 2018 Mazda3 come with forward collision warning and automatic emergency braking as standard on all trim levels.
  
  Mazda to Launch Compression-Ignition Gas Engine by 2019 - Motor Trend
  

 

[Centurion]

Mazda to Launch Skyactiv-X Engine with Compression Ignition in 2019

AUGUST 8, 2017 AT 3:48 PM BY TONY MARKOVICH
View attachment 419130


Mazda may be dipping into the past with its new factory effort to restore first-generation Miatas, but the company otherwise has its sights set on the future. Mazda announced that it is expanding its environmental initiative by setting new efficiency, safety, and sustainability goals for the coming decades. The most significant development is a new generation of engines, dubbed Skyactiv-X, set to launch in 2019. Mazda claims it will be the first commercial gasoline engine to use compression ignition technology.

Known officially as Homogeneous Charge Compression Ignition (HCCI), the technology is something many auto manufacturers have been working on for years. However, issues with narrow powerbands (read: unusable for normal customers) and managing emissions have held up mass-scale implementation. An HCCI engine pressurizes an air-and-fuel mixture until the generated heat detonates it. It is controlled detonation, a condition to be avoided at all costs in normal gasoline engines.

Unlike a diesel, which only always relies on compression ignition, an HCCI engine still employs a spark plug during maximum load, or high power, situations. Basically, Mazda will have the best of both worlds: an engine with the cruising efficiency of a diesel without sacrificing a peppy top end.

The company did not specify which models would get the technology, but it did say that the Skyactiv-X engine will be supercharged to increase power and improve response. Torque output with the new tech also is claimed to be 10 to 30 percent better than that in the current Skyactiv-G models.

The proprietary method is called Spark Controlled Compression Ignition, and Mazda claims it improves efficiency by 20 to 30 percent from its current Skyactiv-G engines. The efficiency and torque gains allow for “much more latitude in the selection of gear ratios.”

The HCCI news comes shortly after the company announced a partnership with Toyota, working on EV technology. Mazda’s overall goal is to cut carbon dioxide emissions in half by 2030, from their 2010 levels. Expect more details on Skyactiv-X later this year.

From C&D

Interesting. I wonder whether the timing is different between spark and non-spark combustion, and how that affect engine vibrations.

I'm also curious to understand what they mean by "maximum load". Is it moderate throttle response, high revs or pedal to the floor?

 

[Giannis]

I wonder whether the timing is different between spark and non-spark combustion

Think, where does the mixture combust in each case? In a spark ignition the spark is basically a point and the flame starts traveling from that point. In combustion ignition, the mixture combusts throughout its volume. Therefore, timing is by definition different, as timing is set in order for the whole mixture to be burnt before the piston reaches TDC.

and how that affect engine vibrations.

Think diesel vs gas engines. In gas engines, the flame front travels radially from the spark point. In diesel engines, the situation is chaotic and so are engine vibrations.

 

[Giannis]

I'm also curious to understand what they mean by "maximum load".

I think it's low revs and full throttle.