What is direct injection technology and which cars have engines that are direct injection engines?

Ecoboost is Ford's general term for engines that will use turbocharging and direct injection in the future.

Extensive use of direct injection in the cylinder.

Among the engine technologies that have been adopted by various plants recently, the hottest technology is in-cylinder direct injection. This diesel-derived technology is now widely used in the, BMW, MERCEDES-BENZ, GM and Toyota (Lexus) models.

Direct in-cylinder injection technology is widely used in the Group, by Audi

The RS4 and R8 RSI engines are one of the most powerful examples of this.

Among them, the Group can be regarded as the most representative example of the introduction of in-cylinder direct injection technology, including Audi and VW, both have listed the in-cylinder direct injection engine called FSI as the high-end power of their models**, and in the top cars of the Audi and VW series, even FSI combined with turbocharging to increase power.

The biggest advantage of the in-cylinder direct injection design of the fuel supply system is that the fuel is injected directly into the combustion chamber at a very high pressure, so in addition to the structure and position of the fuel injector are different from the traditional fuel supply system, the atomization and mixing efficiency of oil and gas is also better. In addition, the control technology of various electronic systems on the car has been greatly improved, and the computer has become more accurate in the interpretation and control of air intake and fuel injection timing, so with the direct injection technology in the cylinder to greatly improve the combustion efficiency of the engine, in addition to the engine to generate greater power, it also has a positive help for environmental protection and energy saving. In addition to the material of the engine with direct injection, the piston and combustion chamber are specially designed

However, the in-cylinder direct injection technology is not invincible, because from an economic point of view, the use of in-cylinder direct injection fuel supply system in addition to the research and development process must spend more costs, in the case of complex and precise component composition, the most expensive components are more expensive than the traditional fuel supply system, so these are also the elements to be overcome in the future in-cylinder direct injection engine.

In-cylinder direct injection is also known as FSI (Fuel

stratified

injection), which is a technology of fuel stratification injection, in which fuel is injected directly into the cylinder from the nozzle. This technology can further improve the thermal efficiency of gasoline engines and reduce gasoline engine emissions. This set of technology, derived from diesel engines, is now widely used.

Advantages of in-cylinder direct injection engines:

The fuel injector can be controlled during layered combustion, and the piston compression stroke reaches the highest point; The fuel injection starts just before the spark plug ignites. In addition, during combustion, the air layer isolates heat, reducing the transfer of heat to the cylinder wall, thereby reducing heat loss and improving the thermal efficiency of the engine.

Disadvantages: It needs to be equipped with high-pressure fuel injectors to improve the atomization degree and mixing efficiency of oil and gas; In addition to the material of the engine, the engine of the direct injection system in the cylinder is more particular, and in order to control the flow direction of the gas during layered combustion, even the shape of the piston and combustion chamber also needs to be specially designed; Most importantly, in-cylinder direct injection requires consistent quality of high-grade fuel.

Explanation: In general, the in-cylinder direct injection technology has the ability to control the autonomous fuel injection, which can make the engine have the most efficient fuel utilization in all operating conditions. The horsepower increase is about 10%, and the fuel consumption is not much different. As a consumer and a manufacturer, there really isn't a reason to say no to this advanced technology.

In addition, the well-established technologies for controlling valve timing and valve lift, such as VVT-I, I-VTEC, MIVEC, etc., as well as turbocharging and supercharging, are all aimed at controlling the efficiency of air entering the cylinder more efficiently. However, the in-cylinder direct injection technology that can improve the final combustion step is still in the process of gradual promotion, but just like the electric injection engine replaced the carburetor in the past, the in-cylinder direct injection technology will definitely be gradually adopted by major manufacturers.

1.In the case of heavy or full load, the in-cylinder direct injection engine injects fuel into the combustion chamber during the intake stroke. Since the fuel bundle moves less than the downward velocity of the piston, the pressure around the fuel bundle is lower and the fuel rapidly diffuses and evaporates, resulting in a homogeneous combustion mixture.

2.The direct injection engine in the cylinder adopts the layered combustion mode under medium and medium load conditions, and the gradient of fuel concentration is gradient distribution, that is, most of the gas distributed near the cylinder wall is air, which effectively prevents heat transfer to the cylinder water jacket and improves the combustion heat efficiency.

3.When the inlet injection engine starts cold, the temperature in the cylinder is low, and the evaporation of the oil is incomplete, resulting in the actual fuel injection far exceeding the fuel injection calculated according to the theoretical air-to-fuel ratio, and it is easy to misfire or incomplete combustion during cold start, increasing HC emissions. The in-cylinder direct injection engine can precisely control the air-to-oil ratio of each empty cycle.

Combined with the stratified combustion direct start technology, HC emissions can be reduced during cold starts, with good transient response.

4. The in-cylinder direct injection engine adopts quality adjustment, and the fuel injection is carried out according to the actual needs of each cylinder, which can reduce the difference between the cylinders and improve the uniformity of each cylinder, generally compared with the intake injection gasoline engine, the uniformity of each cylinder of the in-cylinder direct injection engine can be controlled within 3%.

1.Under heavy or full load conditions, the in-cylinder direct injection engine injects fuel into the combustion chamber during the intake stroke. Since the fuel rod bundle moves less than the piston down velocity, the pressure around the fuel rod bundle is lower and the fuel rapidly diffuses and evaporates, forming a homogeneous combustion mixture.

2.The direct injection engine adopts a layered combustion method under medium and low load conditions, and the fuel concentration gradient presents a gradient distribution, that is, most of the air is distributed near the cylinder wall, which effectively avoids the transfer of heat to the cylinder water jacket and improves the combustion heat efficiency. 3.

In the process of cold starting, the temperature in the cylinder is low, and the evaporation of oil and gas is incomplete, resulting in the actual injection amount far exceeding the injection amount calculated according to the theoretical air-fuel ratio, and the phenomenon of ignition or incomplete combustion is easy to occur during cold starting, which increases HC emissions. The direct-injection engine allows for precise adjustment of the air/fuel ratio for each cycle. Combined with the stratified combustion direct start technology, the HC emission slag can be reduced during cold starting, and it has a good transient response.

4.The in-cylinder direct injection engine adopts quality adjustment and injects fuel according to the actual needs of each cylinder, which can reduce the difference between each cylinder and improve the uniformity of each cylinder. Compared with the intake injection gasoline engine, the uniformity of each cylinder of the direct injection engine in the cylinder can be adjusted within 3% for most of the time.

What are the advantages of in-cylinder direct injection engines? 1.High Performance:

Using the in-cylinder direct injection technology, the fuel is directly injected into the combustion chamber, which avoids the generation of mixed gas in the inlet tract, so that the fuel combustion is more adequate and the performance is better. 2.Low emission:

By precisely adjusting the air-fuel ratio and quality adjustment technology for each cycle, it is possible to reduce the differences between each cylinder and achieve a low emission effect. 3.Joints and beams pin oil:

Direct injection technology enables efficient combustion and avoids fuel waste in the intake tract, resulting in lower fuel consumption. 4.Increase output power:

The use of in-cylinder direct injection technology can increase the power output of the engine, making the performance of the car even better.

1.At low loads, a considerable amount of NOx and high temperatures are generated, so the requirements for the three-way catalytic converter will be high. 2.

The in-cylinder direct injection technology also has high requirements for some hardware facilities, such as the need to equip high-pressure fuel nozzles to improve the atomization degree and mixing efficiency of oil and gas; The engine with direct injection system not only pays more attention to the material, but also requires a special design of the shape of the piston and combustion chamber to control the flow of gas during stratified combustion. On top of that, in-cylinder direct injection requires consistent, high-grade fuel. 3. Because the direct injection in the cylinder cannot be washed out through gasoline like the intake manifold injection, the base of the valve leakage head will lead to serious carbon deposition in the engine after a long time, and a thick layer of carbon deposit will be left on the back of the Qinshou valve, which will affect the ECU's judgment of the air intake volume, and can lead to difficulty in starting in serious cases.

<> "Direct injection engine is an engine that adopts in-cylinder direct injection technology, which is the technology that directly injects fuel into the cylinder and mixes with the intake air, and direct injection is also a kind of electric injection, the full name is called in-cylinder direct injection. So what are the advantages and disadvantages of the in-cylinder direct injection engine?

Advantages of in-cylinder direct injection engines: stratified combustion can control the nozzles, and the spark plugs start to inject instantaneously before the piston compression stroke reaches its highest point; During combustion, the air layer isolates the heat and reduces the heat transfer to the cylinder walls, thereby reducing heat loss and improving the thermal efficiency of the engine.

Disadvantages of in-cylinder direct injection engine: high-pressure injectors are needed to improve the atomization and mixing efficiency of oil and gas. Even the shape of the piston and combustion chamber requires a special design, and most importantly, direct injection in the cylinder requires a consistently high grade of fuel.

The advantages and disadvantages of the in-cylinder direct injection engine are as follows: 1. Advantages: the fuel injector can be controlled during layered combustion, and the fuel injection can be started at the moment when the piston compression stroke reaches the highest point and the spark plug is ignited; 2. Moreover, during combustion, the air layer isolates the heat, reduces the transfer of heat to the cylinder wall, thereby reducing the loss of heat and improving the thermal efficiency of the engine; 3. Disadvantages:

It is necessary to be equipped with high-pressure fuel injectors to improve the atomization degree and mixing efficiency of oil and gas. 4. In order to control the flow direction of gas during stratified combustion, even the shape of the piston and combustion chamber needs to be specially designed, and the most important point is that the direct injection in the cylinder requires stable quality of high-grade fuel.