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Gasoline direct injection Gasoline direct injectionIn internal combustion engines, Gasoline Direct Injection (GDI), also known as Petrol Direct Injection, Direct Petrol Injection, Spark Ignited Direct Injection (SIDI) and Fuel Stratified Injection (FSI), is a variant of fuel injection employed in modern two stroke and four stroke gasoline engines. The gasoline is highly pressurized, and injected via a common rail fuel line directly into the combustion chamber of each cylinder, as opposed to conventional multi point fuel injection that injects fuel into the intake tract, or cylinder port. Directly injecting fuel into the combustion chamber requires high pressure injection whereas low pressure is used injecting into the intake tract or cylinder port. In some applications, gasoline direct injection enables a stratified fuel charge (ultra lean burn) combustion for improved fuel efficiency, and reduced emission levels at low load. The major advantages of a GDI engine are increased fuel efficiency and high power output. levels can also be more accurately controlled with the GDI system. The cited gains are achieved by the precise control over the amount of fuel and injection timings that are varied according to engine load. In addition the engines operate on full air intake. That is, there is no air throttle plate eliminating air throttling losses in some GDI engines, when compared to a conventional fuel injected or carbureted engine, which greatly improves efficiency, and reduces piston 'pumping losses'. Engine speed is controlled by the engine control unit/engine management system (EMS), which regulates fuel injection function and ignition timing, instead of having a throttle plate that restricts the incoming air supply. Adding this function to the EMS requires considerable enhancement of its processing and memory, as direct injection plus the engine speed management must have very precise algorithms for good performance and drivability. The engine management system continually chooses among three combustion modes: ultra lean burn, stoichiometric, and full power output. Each mode is characterized by the air fuel ratio. The stoichiometric air fuel ratio for gasoline is 14.7:1 by weight (mass), but ultra lean mode can involve ratios as high as 65:1 (or even higher in some engines, for very limited periods). These mixtures are much leaner than in a conventional engine and reduce fuel consumption considerably. Ultra lean burn or stratified charge mode is used for light load running conditions, at constant or reducing road speeds, where no acceleration is required. The fuel is not injected at the intake stroke but rather at the latter stages of the compression stroke. The combustion takes place in a cavity on the piston's surface which has a toroidal or an ovoidal shape, and is placed either in the center (for central injector), or displaced to one side of the piston that is closer to the injector. The cavity creates the swirl effect so that the small amount of air fuel mixture is optimally placed near the spark plug. This stratified charge is surrounded mostly by air and residual gases, which keeps the fuel and the flame away from the cylinder walls. Decreased combustion temperature allows for lowest emissions and heat losses and increases air quantity by reducing dilation, which delivers additional power. This technique enables the use of ultra lean mixtures that would be impossible with carburetors or conventional fuel injection.[1][2][3] Stoichiometric mode is used for moderate load conditions. Fuel is injected during the intake stroke, creating a homogeneous fuel air mixture in the cylinder. From the stoichiometric ratio, an optimum burn results in a clean exhaust emission, further cleaned by the catalytic converter. Full power mode is used for rapid acceleration and heavy loads (as when climbing a hill). The air fuel mixture is homogeneous and the ratio is slightly richer than stoichiometric, which helps prevent detonation (pinging). The fuel is injected during the intake stroke. It is also possible to inject fuel more than once during a single cycle. After the first fuel charge has been ignited, it is possible to add fuel as the piston descends. The benefits are more power and economy, However, certain octane fuels have caused exhaust valve erosion.[citation needed]Direct injection may also be accompanied by other engine technologies such as variable valve timing (VVT) or continuous variable cam phasing, tuned/multi path or variable length intake manifolding (VLIM, or VIM), and turbocharging. Water injection or (more commonly) exhaust gas recirculation (EGR) may help reduce the high nitrogen oxides (NOx) emissions that can result from burning ultra lean mixtures; modern turbocharged engines use continuous cam phasing in place of EGR. Tuning up an early generation FSI power plant to generate higher power is difficult, since the only time it is possible to inject fuel is during the induction phase. Conventional injection engines can inject throughout the 4 stroke sequence, as the injector squirts onto the back of a closed valve. A direct injection engine, where the injector injects directly into the cylinder, is limited to the intake stroke of the piston. As the RPM increases, the time available to inject fuel decreases. Newer FSI systems that have sufficient fuel pressure to inject even late in compression phase do not suffer to the same extent; however, they still do not inject during the exhaust cycle (they could but it would just waste fuel). Hence, all other factors being equal, an FSI engine needs higher capacity injectors to achieve the same power as a conventional engine. Some engines overcome this limitation by using both direct injection and multiport fuel injection (Toyota 2GR FSE V6). The invention of direct gasoline injection was by the French inventor of the V8 engine configuration, Leon Levavasseur in 1902.[4] Levavasseur designed the original Antoinette firm's series of V form aero engines, starting with the Antoinette 8V to be used by the aircraft the Antoinette firm built that Levavasseur also designed, flown from 1906 to the firm's demise in 1910, with the world's first V16 engine, using Levavasseur's direct injection and producing some 100hp, flying an Antoinette VII monoplane in 1907. The first post World War I example of direct gasoline injection was on the Hesselman engine invented by Swedish engineer Jonas Hesselman in 1925.[5][6] Hesselman engines used the ultra lean burn principle and injected the fuel in the end of the compression stroke and then ignited it with a spark plug, it was often started on gasoline and then switched over to run on diesel or kerosene. The Hesselman engine was a low compression design constructed to run on heavy fuel oils. Direct gasoline injection was applied during the Second World War to almost all higher output production aircraft powerplants made in Germany (the widely used BMW 801 radial, and the popular inverted inline V12 Daimler Benz DB 601, DB 603 and DB 605, along with the similar Junkers Jumo 210G, Jumo 211 and Jumo 213, starting as early as 1937 for both the Jumo 210G and DB 601), the Soviet Union's (Shvetsov ASh 82FN radial, 1943, Chemical Automatics Design Bureau KB Khimavtomatika) and the US (Wright R 3350 Duplex Cyclone radial, 1944). The first automotive direct injection system used to run on gasoline was developed by Bosch, and was introduced by Goliath and Gutbrod in 1952. This was basically a high pressure diesel direct injection pump with an intake throttle valve set up. (Diesels only change the amount of fuel injected to vary output; there is no throttle.) This system used a normal gasoline fuel pump, to provide fuel to a mechanically driven injection pump, which had separate plungers per injector to deliver a very high injection pressure directly into the combustion chamber. The 1955 Mercedes Benz 300SL, the first production sports car to use fuel injection, used direct injection. The Bosch fuel injectors were placed into the bores on the cylinder wall used by the spark plugs in other Mercedes Benz six cylinder engines (the spark plugs were relocated to the cylinder head). Later, more mainstream applications of fuel injection favored the less expensive indirect injection methods. Research was conducted in the early 1970s with the backing of American Motors Corporation (AMC) to develop a Straticharge Continuous Fuel Injection (SCFI) system.[7] The conventional spark ignited internal combustion AMC straight 6 engine was modified with a redesigned cylinder head. The system incorporated a mechanical device that automatically responded to the engine's airflow and loading conditions with two separate fuel control pressures supplied to two sets of continuous flow injectors.[8] Flexibility was designed into the SCFI system for trimming it to a particular engine.[9] Prototype "straticharge" engine road testing was performed using a 1973 AMC Hornet, but the mechanical fuel controls had teething problems.[10] The Ford Motor Company developed a stratified charge engine in the late 1970s called "PROCO" (programmed combustion)[11][12] using a unique high pressure pump and direct injectors. At least one hundred and fifteen (115) Crown Victoria cars were built at Ford's Atlanta Assembly in Hapeville, Georgia using a PROCO V8 engine. The project was canceled for several reasons: electronic controls, a key element, were in their infancy; pump and injector costs were extremely high; and lean combustion produced nitrogen oxides in excess of near future United States Environmental Protection Agency (EPA) limits.[13] Also, the PROCO system was being launched in the late 1970s, a time of the second "gas crisis" in the US, which drove fuel costs higher. PROCO had been initially developed for Ford's 460 Cubic inch V8 engine line, later applied to the 351, and eventually the 302. Mitsubishi was the first with a GDI engine in the Japanese market with its Galant/Legnum's 4G93 1.8L inline four.[14][15] It was subsequently brought to Europe in 1997 in the Carisma,[16] although the engine was a failure due to high emissions and poor fuel efficiency.[17] It also developed the first six cylinder GDI powerplant, the 6G74 3.5L V6, in 1997.[18] Mitsubishi applied this technology widely, producing over one million GDI engines in four families by 2001.[19] Although in use for many years,, on September 11, 2001 MMC claimed a trademark for the acronym 'GDI' (with an uppercase final "I").[20] In 1997 Nissan released the Leopard featuring the VQ30DD equipped with direct injection.[21] In 1998, Toyota's D4 direct injection system first appeared on various Japanese market vehicles equipped with the SZ and NZ engines.[22][23][24] Toyota later introduced its D4 system to European markets with the 1AZ FSE engine found in the 2001 Avensis.[25] and US markets in 2005 with the 3GR FSE engine found in the Lexus GS 300. Toyota's 2GR FSE V6 first found in the Lexus IS 350 uses a more advanced direct injection system, which combines both direct and indirect injection using two fuel injectors per cylinder, a traditional port fuel injector (low pressure) and a direct fuel injector (high pressure) in a system known as D4 S.[26] In 1999, Renault introduced the 2.0 IDE (Injection Directe Essence),[27] first on the Megane. Rather than following the lean burn approach, Renault's design uses high ratios of exhaust gas recirculation to improve economy at low engine loads, with direct injection allowing the fuel to be concentrated around the spark.[28] Later gasoline direct injection engines have been tuned and marketed for their high performance as well as increased fuel efficiency. PSA Peugeot Citron, Hyundai, and Volvo entered into a development agreements and licensed Mitsubishi's GDI technology in 1999.[29][30][31][32][33] The Mitsubishi engines were also produced in the NedCar factory and used in the 1.8 L Carisma and the GDI powered Volvo S40/V40 models.[34][35] In 2000, the Volkswagen Group introduced its gasoline direct injection engine in the Volkswagen Lupo, a 1.4L inline four unit, under the product name "Fuel Stratified Injection" (FSI) and "Turbo Fuel Stratified Injection" (TFSI).[36] The technology was adapted from Audi's Le Mans prototype race car R8. Volkswagen Group marques use direct injection in its turbocharged 2.0L TFSI and naturally aspirated 2.0L FSI four cylinder engines. Later, a 1.6L inline four unit was introduced in the MY 2002 Volkswagen Golf Mk4/Jetta/Bora, a 1.4L in the MY 2002 Volkswagen Polo Mk4 and a 2.0L in the model year 2003 Audi A4. PSA Peugeot Citron introduced its first GDi (HPi) engine in 2000 in the Citron C5 and Peugeot 406. It was a 2.0 liter 16 valve EW10 D unit with 140hp (104kW), the system was licensed from Mitsubishi.[31][35][37] In 2002, the Alfa Romeo 156 with a direct injection engine, the JTS (Jet Thrust Stoichiometric) went on sale[38] and today the technology is used on almost every Alfa Romeo engine. In 2003, Ford debuted a 1.8L Duratec SCi naturally aspirated engine for the Mondeo.[39] Ford introduced its first European Ford engine to use direct injection technology in 2001, badged SCi (Smart Charge injection) for Direct Injection Spark Ignition (DISI).[39] The range will include some turbocharged derivatives, including the 1.0L, three cylinder turbocharged unit showcased at the 2002 Geneva Show.[39] In 2003,woolrich outlet Natural Treat, BMW introduced a low pressure gasoline direct injection N73 V12.[40] This initial BMW setup could not enter lean burn mode, but the company introduced its second generation High Precision Injection (HPI) system on the new turbocharged N54 straight 6 in 2006,hogan outlet scarpe How Hybrid Cars Work, which used high pressure injectors.[41] This system surpasses many others with a wider envelope of lean burn time, increasing overall efficiency.[42] PSA is cooperating with BMW on a new line of engines that made its first appearance in the 2007 MINI Cooper S. Honda released their own direct injection system on the Stream sold in Japan.[43] Honda's fuel injector is placed directly atop the cylinder at a 90 degree angle rather than a slanted angle.[43]hogan sito ufficiale woolrich sito ufficiale hogan uomo outlet giuseppe zanotti design peuterey sito ufficiale chaussures louboutin pas cher canada goose pas cher hogan outlet 2015 louboutin femme scarpe hogan outlet online doudoune moncler site officiel woolrich outlet online air max 90 pas cher roshe run pas cher moncler outlet 

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