HCCI(Homogeneous Charge Compression Ignition)..is it next big thing in diesel?

[dbuzz]

Homogeneous Charge Compression Ignition, or HCCI, is a relatively new combustion technology.

It is a hybrid of the traditional spark ignition (SI) and the compression ignition process (such as a Diesel engine) the continuing effort to assess the possibility of an HCCI engine to provide low emission, high efficiencypower generation for the ever growing energy demands of this planet.

Is this a possible challenger of CRDI?

[alwayz_yummy]

paano concept nito of injecting fuel??premixed na kaya before ignition? will this have kaya another new cycle?

[dbuzz]

paano concept nito of injecting fuel??premixed na kaya before ignition? will this have kaya another new cycle?

[SIZE=3]HCCI has characteristics of the two most popular forms of combustion used in IC engines:[/SIZE]
[SIZE=3][/SIZE]
[SIZE=3] ]]] homogeneous charge spark ignition ([/SIZE][SIZE=3]gasoline[/SIZE][SIZE=3] engines) - here, the fuel and oxidizer are mixed together however, rather than using an electric discharge to ignite a portion of the mixture, the concentration and temperature of the mixture are raised by compression until the entire mixture reacts simultaneously.[/SIZE]
[SIZE=3][/SIZE]
[SIZE=3]]]] stratified charge compression ignition ([/SIZE][SIZE=3]diesel[/SIZE][SIZE=3] engines). In stratified charge compression ignition also relies on temperature increase and concentration resulting from compression, but combustion occurs at the boundary of fuel-air mixing, caused by an injection event, to initiate combustion.[/SIZE]

[SIZE=3]The defining characteristic of HCCI is that the ignition occurs at several places at a time which makes the fuel/air mixture burn nearly simultaneously. There is no direct initiator of combustion. This makes the process inherently challenging to [/SIZE][SIZE=3]control[/SIZE][SIZE=3]. However, with advances in microprocessors and a physical understanding of the ignition process, HCCI can be controlled to achieve [/SIZE][SIZE=3]gasoline engine[/SIZE][SIZE=3]-like emissions along with [/SIZE][SIZE=3]diesel engine[/SIZE][SIZE=3]-like efficiency. In fact, HCCI engines have been shown to achieve extremely low levels of Nitrogen oxide emissions (NOx) without after-treatment [/SIZE][SIZE=3]catalytic converter[/SIZE][SIZE=3]. The unburned hydrocarbon and carbon monoxide emissions are still high (due to lower peak temperatures), as in gasoline engines, and must still be treated to meet [/SIZE][SIZE=3]automotive emission regulations[/SIZE][SIZE=3].[/SIZE]
[SIZE=3][/SIZE]
[SIZE=3]HCCI engines have a long history, even though HCCI has not been as widely implemented as spark ignition or diesel injection. It is essentially an [/SIZE][SIZE=3]Otto combustion cycle[/SIZE][SIZE=3]. In fact, HCCI was popular before electronic [/SIZE][SIZE=3]spark ignition[/SIZE][SIZE=3] was used. One example is the [/SIZE][SIZE=3]hot-bulb engine[/SIZE][SIZE=3] which used a hot vaporization chamber to help mix fuel with air. The extra heat combined with compression induced the conditions for combustion to occur.[/SIZE]

[dbuzz]

Homogeneous Charge Compression Ignition, or HCCI, is a relatively new combustion technology.

It is a hybrid of the traditional spark ignition (SI) and the compression ignition process (such as a Diesel engine) the continuing effort to assess the possibility of an HCCI engine to provide low emission, high efficiencypower generation for the ever growing energy demands of this planet.

Is this a possible challenger of CRDI?

so i guess its really very new kaya halos walang naka comment. matagal ng may research dito kaya lang ang talagang problema ay kung papaano i monitor ang ngayayari sa loob ang combustion chamber. kaya nga sa ngayon dahil sa mga microchips na masyadong sophsticated ay pwede na.

[mbeige]

Do a search on "DiesOtto" a new Mercedes-Benz designed engine that also uses gasoline and diesel engine technologies to have variable compression ability while still maintaining the compress-ignite principle.

It has been said to produce 240hp in a 1.8L engine but can also go 40MPG in an S-class sized vehicle.

[dbuzz]

*mbeige: `Do a search on "DiesOtto" a new Mercedes-Benz designed engine that also uses gasoline and diesel engine technologies to have variable compression ability while still maintaining the compress-ignite principle.

It has been said to produce 240hp in a 1.8L engine but can also go 40MPG in an S-class sized vehicle.

well, who knows, kasi talagang mabilis ang advancement of technology now a days mostly in the fields of microchips and alloys/chemistry no wonder that there are a lot of old and new ideas surfacing or resurfacing out gaya lang nitong Mercedes-Benz DiesOtto by Nikolaus August Otto is an experimental (also called concept-engine) automobile engine that is said "to incorporate the benefits of a diesel engine, but runs on regular old unleaded." It is also fitted with a starter alternator to further increase its mileage in town conditions. Its principle of operation is to operate using controlled auto ignition on low demanding conditions (even shutting down the engine altogether at a stop thanks to the starter alternator), and harvest the full benefits of turbocharging and direct injection on high demanding conditions.
The company’s powerful and economical BLUETEC diesel engine diesel has already been available in the US in the E-Class since 2006, and it will also become available in Europe from the end of this year.

The E 300 BLUETEC will be by far the cleanest diesel in its class, and will meet the requirements of the EU5 exhaust emission standards in full.
"Our next goal will now be to make the gasoline engine as economical as a diesel. All the preconditions for this are provided by our DiesOtto concept, which incorporates the foremost strengths of both the gasoline engine and diesel engine," says Prof. Dr. Herbert Kohler, Head of Group Research & Advanced Engineering Vehicle and Powertrain; Chief Environmental Officer of DaimlerChrysler.
The result of this " marriage " is a four-cylinder unit with a displacement of just 1.8 litres, which combines the strengths of the low-emission gasoline engine with the fuel economy of a diesel.

[dbuzz]

ito ang latest sa HCCI.

Its latest effort is the HCCI internal combustion engine, a spark-ignition piston engine that can operate as a compression ignition motor, similar to a diesel. GM installed a version of the engine in both a Saturn Aura and an Opel Vectra and let us drive them around its proving grounds in Milford, Michigan.


General Motors says HCCI (Homogeneous Charge Compression Ignition) can yield a 15 percent improvement in fuel economy. But there are a few caveats. First, GM Powertrain Chief Tom Stephens says the technology won't likely reach production before 2015. And second, this impressive number includes the cumulative efficiency of variable valve timing and lift as well as direct injection, both of which must be in place for compression ignition to operate.

Compression ignition is all about the temperature inside the combustion chamber. In compression-ignition mode, the exhaust valves close earlier, trapping some of the heated air from the previous combustion cycle. This warms the incoming fuel mixture sufficiently to produce ignition once it's compressed by the piston. Clever stuff. But when the engine is under load — while accelerating, for example — the engine must transition back into spark mode to make full power.