Differences between diesel and gasoline engines

An engine produces power. The internal combustion engine produces power by burning fuel inside a combustion chamber within the engine. This type of engine provides power for automobiles, tractors, motorcycles and many other types of equipment.

The diesel engine is a type of internal combustion engine that produces power by compression-ignition. At first glance these engines may look like spark-ignition engines, but upon closer inspection it is easy to see that they differ in many ways.

Internal combustion engines are classified by their method of ignition: either spark-ignition (gasoline engines) or compression ignition (diesel engines).

There are some major differences between a diesel and a gasoline engine that can be easily observed, first of all, it is the presence of an injection pump and the fuel lines connecting the pump to the injector nozzles in the cylinders.

There are some other differences between these two types of engines that should be mentioned too:

- Diesel engines require more air for operation than do other internal combustion engines that run on liquid fuel;

- Unlike gasoline engines, diesel engines have no ignition system, so there are no spark plugs no coil, magneto, distributor or ignition wiring;

- Diesel engines draw in only air on the intake (admission) stroke whereas gasoline engines draw in a mixture of fuel and air;

- A diesel engine compresses the air before the fuel is introduced. In a gasoline engine the fuel is picked up by the air as it passes through the carburetor so that the vaporized fuel is compressed along with the air;

- Diesel engines use greater a compression ratio than do gasoline engine;

- A diesel engine requires a high-pressure pump to inject the fuel into the compressed air in the cylinder;

- Each cylinder in the diesel engine has a fuel injection nozzle or injector that sprays fuel into the hot, compressed air;

- Diesel engines are heavier than are gasoline engines of the same horse-power. Since diesel engines must operate with high cylinder pressure the engines should be constructed with heavier materials to withstand the greater pressure;

- In a diesel engine the throttle control regulates only the fuel. Engine speed is controlled by changing the amount of fuel injected into the compressed air in the cylinder;

- Diesel engines are stopped by shutting off the fuel to the cylinders by a manually operated control or by an electric solenoid which acts on the injection pump governors. Gasoline engines are stopped by cutting off the spark from the spark plugs.

Answer these questions:

а)

1. Каким образом в ДВС создается механическая энергия?

2. Какие существуют два типа двигателей внутреннего сгорания?

3. В чем заключаются основные различия между дизельным и бензиновым двигателями?

b)

1. How does the internal combustion engine produce power?

2. What are the two types of internal combustion engines?

3. What are the major differences between a diesel and a gasoline engine?

4. What are some other differences between these two types of engines?

Read Text 3 and translate it into Russian. Make up your own Vocabulary. Try to memorize the main terms.

Text 3