Diesel engine is an engine that burns diesel to obtain energy release. The advantages of it are high power and good economic performance. At the same time, the advantages of diesel engine in energy saving and carbon dioxide emission are irreplaceable by all thermal engines including gasoline engine. Therefore, the diesel engine has become the power device of many machines. It is very necessary to know the characteristics of various types of engines.
Here is the content list:
What is diesel engine?
What are the types of diesel engines?
What are the characteristics of these engines?
Diesel engine obtains energy release by burning diesel. The working process of diesel engine is much the same as that of gasoline engine. Each working cycle also experiences four strokes: intake, compression, work and exhaust. However, because the fuel of diesel engine is diesel, its viscosity is higher than that of gasoline, and it is not easy to evaporate, but its spontaneous combustion temperature is lower than that of gasoline, so the formation and ignition mode of combustible mixture are different from that of gasoline engine. The main difference is that the mixture in the cylinder of diesel engine is compression ignition, not ignition. When the diesel engine works, air enters the cylinder. When the air in the cylinder is compressed to the end point, the temperature can reach 500-700 ℃, and the pressure can reach 40-50 atmospheres. When the piston is close to TDC, the high-pressure pump on the engine injects diesel oil into the cylinder at high pressure. The diesel oil forms fine oil particles and mixes with high-pressure and high-temperature air. The diesel mixture burns itself, expands violently, and generates explosive force to push the piston downward to do work. At this time, the temperature can reach 1900-2000 ℃, and the pressure can reach 60-100 atmospheres. The power generated is very large, so the diesel engine generates power motivation is widely used in large diesel vehicles.
The application of diesel engine is very extensive, and it also occupies an important position in the industrial chain. There are many types of diesel engines. When purchasing diesel engines, we should first understand the types of diesel engines. It can be divided into these types according to the use: automotive engine, construction engine, generator engine and marine engine.
For automobile engine
A few decades ago, people once gave up diesel cars. The image of diesel engine with large volume, high noise and bad smell still remains in many people's memory. However, after decades of development, modern diesel engine has become a clean emission, energy saving power, is a feasible transitional technology solutions. Automobile engine has the following characteristics:
(1) It has high energy density (the effective thermal efficiency of large low-speed turbocharged diesel engine has exceeded 50%) and low fuel consumption rate, which is very important to save energy and improve economic benefits.
(2) Good fuel economy
(3) The emission of greenhouse gas is low, and its carbon dioxide emission is about 30-35% lower than that of gasoline engine. However, the exhaust gas contains more harmful components (no, particulate matter, etc.) and has greater noise, which has attracted attention in environmental protection.
(4) It has a wide range of power and speed (power 1-6558okw, speed 54-5000r / min), so it has a wide range of applications
(5) Compared with gasoline engine, the structure is more complex, the material and process requirements of parts are higher, the manufacturing cost is higher, and the quality is higher.
(6) New technologies (electronic control, supercharging, exhaust gas recirculation, new materials) are widely used and rapidly developed. The investment in product R & D and production equipment is large, which belongs to technology intensive and capital intensive products.
For generator engine and marine engine
Generator diesel set is a kind of power supply equipment which takes diesel engine as prime mover and drives synchronous generator to generate electricity. It is a kind of power generation device with quick start, convenient operation and maintenance, less investment and strong adaptability to the environment.
Compared with marine engine, generator diesel set has the following characteristics:
(1) Small volume, light weight and simple system per unit of output, which are generally integrated. Therefore, the construction speed of diesel electromechanical station is fast.
(2) The thermal efficiency of diesel power generation is high, and the fuel consumption per unit output has little change under part load or light load.
(3) The starting, loading and stopping time of generator diesel set is short. It can be started at any time and is more suitable for emergency power supply.
(4) The operation and maintenance of generator diesel set is simpler and more convenient than that of steam turbine generator set.
However, the diesel generator set also has some disadvantages: ① it can only use liquid fuel, the fuel price is expensive, so the cost of electric energy is high. ② Diesel engine wear is bigger, life is shorter, maintenance is more frequent. The operation stability and overload capacity are worse than those of steam power plant. ③ In operation, the vibration and noise of the unit are large, and the operation conditions of workers are poor. ④ The magnetic pole surface of the generator must be equipped with a brake coil to facilitate the start and stop of the unit.
When choosing diesel engine, a lot of information about the equipment needs to be understood. For example, model, performance and so on. If you want to know more, we can provide you with the best service. Please contact xxx company.