Describe the concept of Gasoline Direct Injection (GDI)

Describe the concept of Gasoline Direct Injection (GDI)
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Gasoline Direct Injection (GDI), also known as Petrol Direct Injection. This system is 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, Directly injecting fuel into the combustion chamber requires high pressure injection. The GDI engines operate on full air intake; there is no air throttle plate. Engine speed is controlled by the engine control unit. In this only the combustion air flows through open intake valve on the induction stroke. 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, 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.

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Related questions

What is GDI? State its advantages.

Description : What is GDI? State its advantages. 

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Description : Describe the working of high pressure fuel pump. 

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Description : With the help of suitable sketch describe the working of pressure regulator.

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Description : Draw a labeled block of LPG conversion kit. Describe its working.

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Description : Describe the working of fuel injector with neat sketch

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Description : Describe DTSI system. Write two advantage of it. 

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Description : Describe glow plug. Why and where it is used.

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Description : Describe any four variable affection detonations.

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Describe construction and working of TBI system with suitable sketch.

Description : Describe construction and working of TBI system with suitable sketch.

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Description : State four drawbacks of carbureted SI engine 

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Explain Evaporative emission control system.

Description : Explain Evaporative emission control system.

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Explain Delay Period in detail.

Description : Explain Delay Period in detail.

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What are the advantages of V.V.T?

Description : What are the advantages of V.V.T?

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Description : Sketch and Explain F-head combustion chamber.

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Explain working of LPG kit with labeled block diagram.

Description : Explain working of LPG kit with labeled block diagram.

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Explain engine design modification parameter to control emissions.

Description : Explain engine design modification parameter to control emissions.

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Explain the working computer controlled EGR system.

Description : Explain the working computer controlled EGR system.

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Description : List the various fuels used in I.C. engines. Write the properties of Biodiesel Fuels used in I. C. engine.

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State the effect of compression ratio and turbulence on ignition lag.

Description : State the effect of compression ratio and turbulence on ignition lag.

Last Answer : Effect of engine variables on ignition lag  1) Compression ratio: A higher compression ratio increases the pressure and temperature of the working mixture and decreases the concentration of the residual gases. ... . For this reason. It becomes necessary to advance the spark timing at higher speed. 

What is diesel smoke? State two methods to control diesel smoke.

Description : What is diesel smoke? State two methods to control diesel smoke.

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Explain the working of series hybrid vehicle.

Description : Explain the working of series hybrid vehicle.

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What does VTEC stands for? State advantages of it.

Description : What does VTEC stands for? State advantages of it.

Last Answer : VTEC stands for Variable valve timing and electronic lift control. In VTEC, the valve timing and the valve lift is controlled using ECU to provide efficient breathing of engine and efficient performance of ... GDI is capable of using very lean mixture i.e. 65:1 while using VTEC Improve drivability