Gasoline Direct Injection

[tomthorp]

4 GM Brands to get Orbital Direct Injection

Australasian Business Intelligence, July 2, 2002 Delphi to give Orbital a run at last.
Full Text: COPYRIGHT 2002 News provided by Comtex.

ABIX via COMTEX) -- Perth-based Orbital Engine Corporation has finally had its fuel injection technology accepted for use in the mass vehicle market. The first vehicles to use the technology are not expected to be available until 2005. Delphi has reported that it is in negotiations with at least four brands to use the technology in future four-cylinder models. Delphi is a major component supplier to the global automotive industry, and holds the rights to manufacture and sell the technology as part of its engine management system. It is believed that General Motors will have access to the fuel-saving technology first. The technology will then be made available to subsidiaries and alliance partners Saab Automobile, Adam Opel, Subaru and Suzuki. Delphi has been testing a four-stroke engine fitted with the Orbital system for system integration and durability for the past 18 months. The air-assisted, direct injection system produces a 10 to 20% saving in fuel, Delphi has said. Orbital's technology is already used in two-strike motorbike and marine engines.

Publication Date: 3 July 2002

[Mojocvh]

Bit late with that patent Audi have it on the road (and race track) now and going back a few months too.........MoJo

[tomthorp]

Hi MoJo, The big difference between Orbital's system and the other HPDI(High Pressure Direct Injection) systems is that Orbital's system works. It works with pump gas now available and does not require botiqe 10 ppm Low Sulfer fuel. OCP also does not require expensive exhaust after treatment like HPDI. Orbital is currently suppling injectors and systems to many 2S engine manufacturers now. 4S engines are being tested by several big auto companies as we speak.
Full disclosure: I do own stock in OE(OEC in Au and Germany). Myself and 142 other interested people discuss it in detail at http://groups.yahoo.com/group/oec2/messages/?expand=1, The OE website is also full of valuble info including many tech papers.

I don't want to try to explain the whole system(s) here, but will note the big differencein OCP. In OCP(Orbital Combustion Process) compressed air and fuel are mixed in the injector at relatively low pressures(6-8 bar). This mixture is then injected into the cylinder and as soon as the mixture enters the lower pressure, the compessed air expands violently and sheers/rips the fuel into small(8 micron) droplets. This size is ideal for combustion.

In an HPDI system the gasoline is injected at high pressure(100=300 or more bar) and generally impinges on a "cup" in the cylinder head, to try to "bust" up the fuel into smaller droplets. Usually the best they can do is bout 40 microns. The wall wetting caused by the impingement causes many problems with Excessive NOX being one of them. This excessive NOX causes the system to require very expensive after treatment systems and use of botiuqe fuels.

Have a nice day, Tom

[mondeoman]

quote:
In OCP(Orbital Combustion Process) compressed air and fuel are mixed in the injector at relatively low pressures(6-8 bar). This mixture is then injected into the cylinder and as soon as the mixture enters the lower pressure, the compessed air expands violently and sheers/rips the fuel into small(8 micron) droplets. This size is ideal for combustion.

In an HPDI system the gasoline is injected at high pressure(100=300 or more bar) and generally impinges on a "cup" in the cylinder head, to try to "bust" up the fuel into smaller droplets. Usually the best they can do is bout 40 microns. The wall wetting caused by the impingement causes many problems with Excessive NOX being one of them.

Try closer to 2000 bar in the latest systems.... much better atomisation and fuelling control, expecially with multi hole nozzles (5, 7, 9 or 11 are common), and it doesn't require a "pip" for fuel break up - this occurs because of the nozzle hole size (measured in microns).

Just FWIW.