That the future of the automobile industry is electric vehicles (battery or fuel cell) is increasingly peaceful — only someone very unaware can say otherwise. However, in this matter where opinions tend to polarize, the same consideration is required in the considerations that are made about the future of combustion engines.
The combustion engine is not yet exhausted, and there are several signs to that effect. Let's just remember a few:
- You synthetic fuels , which we have already talked about, could become a reality;
- Mazda remains firm in the engine and technology development that not so long ago seemed impossible to put into production;
- Even Nissan/Infiniti, which bets so much on electric cars, have shown that there is still more "juice" to squeeze out of the old orange which is the combustion engine;
- Toyota has a new 2.0 liter engine (mass-produced) with a record thermal efficiency of 40%
Yesterday Bosch gave another slap of white gloves — still dirty from the Dieselgate… did you like the joke? — on those who insist on trying to bury the old combustion engine. The German brand announced with pomp and circumstance a "mega-revolution" in diesel engine emissions.
As you can see, the internal combustion engine is alive and kicking. And as if these arguments weren't enough, the University of Wisconsin-Madinson discovered yet another technology capable of combining the Otto (petrol) and Diesel (diesel) cycles simultaneously. It's called Reactivity Controlled Compression Ignition (RCCI).
An engine that runs on diesel and gasoline… at the same time!
Sorry for the gigantic introduction, let's get to the news. The University of Wisconsin-Madison has developed an RCCI engine capable of achieving a thermal efficiency of 60% — that is, 60% of the fuel used by the engine is converted into labor and is not wasted in the form of heat.It should be noted that these results were achieved in laboratory tests.
For many, it was considered impossible to reach values of this order, but once again the old combustion engine surprised.
How does RCCI work?
The RCCI uses two injectors per cylinder to mix low-reacting fuel (petrol) with high-reacting fuel (diesel) in the same chamber. The combustion process is fascinating — petrolheads don't need much to be fascinated.
First, a mixture of air and gasoline is injected into the combustion chamber, and only then is diesel injected. The two fuels mix as the piston approaches the top dead center (PMS), at which point another small amount of diesel is injected, which triggers ignition.
This form of combustion avoids hot spots during combustion — if you don't know what "hot spots" are, we've explained in this text about particulate filters in gasoline engines. As the mixture is highly homogenized, the explosion is more efficient and cleaner.
For the record, Jason Fenske from EngineeringExplained made a video explaining everything, if you don't want to understand just the basics:
With this study from the University of Wisconsin-Madison, the concept was proven to work, but it still needs further development before it reaches production. In practical terms, the only drawback is the need to top up the car with two different fuels.
Source: w-ERC