Common rail
Common rail direct fuel injection is a direct
Common rail injection is widely used in diesel engines. It is also the basis of gasoline direct injection systems used on petrol engines.
History
Vickers pioneered the use of common rail injection in submarine engines. Vickers engines with the common rail fuel system were first used in 1916 in the G-class submarines. It used four plunger pumps to deliver a pressure up to 3,000 pounds per square inch (210 bar; 21 MPa) every 90° of rotation to keep the fuel pressure adequately constant in the rail. Fuel delivery to individual cylinders could be shut off by valves in the injector lines.[1] Doxford Engines used a common rail system in their opposed-piston marine engines from 1921 to 1980, where a multicylinder reciprocating fuel pump generated a pressure around 600 bars (60 MPa; 8,700 psi), with the fuel being stored in accumulator bottles.[2] Pressure control was achieved by an adjustable pump discharge stroke and a "spill valve". Camshaft-operated mechanical timing valves were used to supply the spring-loaded Brice/CAV/Lucas injectors, which injected through the side of the cylinder into the chamber formed between the pistons. Early engines had a pair of timing cams, one for ahead running and one for astern. Later engines had two injectors per cylinder, and the final series of constant-pressure turbocharged engines was fitted with four injectors per cylinder. This system was used for the injection of both diesel and heavy fuel oil (600cSt heated to a temperature near 130 °C).
Common rail engines have been used in marine and
The common rail system prototype for automotive engines was developed in the late 1960s by Robert Huber of Switzerland, and the technology was further developed by Dr. Marco Ganser at the Swiss Federal Institute of Technology in Zurich, later of Ganser-Hydromag AG (est. 1995) in Oberägeri.
The first common-rail-Diesel-engine used in a road vehicle was the MN 106-engine by East German VEB IFA Motorenwerke Nordhausen. It was built into a single IFA W50 in 1985. Due to a lack of funding, the development was cancelled and mass production was never achieved.[3]
The first successful use in a mass production vehicle began in Japan by the mid-1990s. Dr. Shohei Itoh and Masahiko Miyaki of the
Modern common rail systems, although working on the same principle, are governed by an
model. In 2001, common rail made its way into pickup trucks with the 6.6 liter Duramax LB7 V8 used in Chevrolet Silverado and GMC Sierra HD models. Dodge and Cummins implemented this in 2003, and Ford adopted this technology in 2008 with the Navistar-built 6.4L Powerstroke. Today, all diesel pickup trucks use common rail systems.Applications
The common rail system is suitable for all types of road cars with diesel engines, ranging from
Acronyms and branding used
The automotive manufacturers refer to their common rail engines by their own brand names:
- Ashok Leyland: CRS (used in U Truck and E4 Busses)
- Audi: TDI, BiTDi The "Bi" stands for BiTurbo
- BMW Group (BMW and Mini): d (also used in the Land Rover Freelander as TD4 and the Rover 75 and MG ZTas CDT and CDTi), D and SD
- Chrysler CRD
- Citroën: HDi, e-HDi and BlueHDi
- Scania: XPI (developed under joint venture)
- Boschinjectors)
- Daimler: CDI
- JTD(also branded as MultiJet, JTDm, and by supplied manufacturers as TDi, CDTi, TCDi, TiD, TTiD, DDiS and QuadraJet)
- Powerstroke) and EcoBlue Diesel
- GM: VCDi (licensed from VM Motori) and Duramax Diesel
- Honda: i-CTDI and i-DTEC
- Kia and Genesis: CRDi
- IKCO: EFD
- Isuzu: iTEQ, Ddi and DI TURBO
- Jaguar: d
- Jeep: CRD and EcoDiesel
- Komatsu: Tier3, Tier4, 4D95 and higher HPCR-series
- Land Rover: TD4, eD4, SD4, TD6, TDV6, SDV6, TDV8, SDV8
- Lexus: d (e.g. 450d and 220d)
- Mahindra: CRDe, m2DiCR, mEagle, mHawk, mFalcon and mPower (Trucks)
- Maserati: Diesel
- PSA Peugeot Citroënjoint venture) and earlier DiTD
- Mercedes-Benz: CDI and d
- Mitsubishi: Di-D
- Nissan: DDTi
- Opel/Vauxhall: DTI, CDTI, BiTurbo CDTI, CRI, Turbo D and BiTurbo D
- Porsche: Diesel
- Proton: SCDi
- Groupe PSA (Peugeot, Citroën and DS): HDi, e-HDi or BlueHDi (developed under joint venture with Ford) – See PSA HDi engine
- Nissan: dCi and BLUEdCi (Infiniti uses some dCi engines as part of the Renault-Nissan Alliance, branded d)
- Saab: TiD (The 2.2 turbo diesel engine was also called "TiD", but it didn't have Common rail) and TTiD The double "T" stands for Twin-Turbo
- SsangYong: XDi, eXDI, XVT or D
- Subaru: TD, D or BOXER DIESEL (as of Jan 2008)
- Suzuki: DDiS
- ),3.3 L Turbotronn and 5L Turbotronn ( used in M&HCV Trucks).
- Toyota: D-4D and D-CAT
- unit injectorengines). Bentley term their Bentayga diesel simply Diesel
- PSA Peugeot Citroën), Volvo PentaD-series engines
Principles
Solenoid or
Common rail engines require a very short to no heating-up time, depending on the ambient temperature, and produce lower engine noise and emissions than older systems.[10]
Diesel engines have historically used various forms of fuel injection. Two common types include the unit-injection system and the distributor/inline-pump systems. While these older systems provide accurate fuel quantity and injection timing control, they are limited by several factors:
- They are cam driven, and injection pressure is proportional to engine speed. This typically means that the highest injection pressure can only be achieved at the highest engine speed and the maximum achievable injection pressure decreases as engine speed decreases. This relationship is true with all pumps, even those used on common rail systems. With unit or distributor systems, the injection pressure is tied to the instantaneous pressure of a single pumping event with no accumulator, thus the relationship is more prominent and troublesome.
- They are limited in the number and timing of injection events that can be commanded during a single combustion event. While multiple injection events are possible with these older systems, it is much more difficult and costly to achieve.
- For the typical distributor/inline system, the start of injection occurs at a predetermined pressure (often referred to as pop pressure) and ends at a predetermined pressure. This characteristic results from "dumb" injectors in the cylinder head which open and close at pressures determined by the spring preload applied to the plunger in the injector. Once the pressure in the injector reaches a predetermined level, the plunger lifts and injection starts.
In common rail systems, a high-pressure pump stores a reservoir of fuel at high pressure — up to and above 2,000 bars (200 MPa; 29,000 psi). The term "common rail" refers to the fact that all of the
Third-generation[
See also
References
- ISBN 978-0-917308-06-2.
- ^ "Doxford Engine Reference". Archived from the original on 2007-12-20.
- ^ "Nordhäuser an Entwicklung des weltweit ersten Common-Rail-Diesels beteiligt – IFA-Museum öffnet zur Nordhäuser Museumsnacht". meinanzeiger.de. 25 March 2015. Archived from the original on 2020-10-28. Retrieved 2022-03-03.
- ^ "240 Landmarks of Japanese Automotive Technology - Common rail ECD-U2". Jsae.or.jp. Archived from the original on 2009-09-08. Retrieved 2009-04-29.
- ^ "Diesel Fuel Injection". DENSO Global. Archived from the original on 2011-08-07. Retrieved 2011-08-03.
- ^ "Fiat Rebirth of a carmaker". economist.com. 2008-04-24. Archived from the original on 2009-09-08. Retrieved 2008-05-01.
- ^ "New Powertrain Technologies Conference". autonews.com. Archived from the original on 2013-07-03. Retrieved 2008-04-08.
- ^ "Denso targets French, US automakers : World's No. 4 supplier will grow organically, not by acquisitions". Europe.autonews.com. 2005-10-17. Retrieved 16 May 2018.
- ^ (multistroke injection) See BMW 2009 Brochure for 3 series
- ^ "Archived copy". www.carservicesalisbury.com. Archived from the original on 14 May 2018. Retrieved 15 January 2022.
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: CS1 maint: archived copy as title (link) - ^ "DENSO Develops a New Diesel Common Rail System With the World's Highest Injection Pressure| News | DENSO Global Website". DENSO Global Website. 2013-06-26. Archived from the original on 2017-10-13.