Since the piston internal combustion engine came out in the 1960s, it has been a relatively perfect machine through continuous improvement and development.
It is widely used because of its high thermal efficiency, wide range of power and speed, convenient matching and good maneuverability.
All kinds of cars, tractors, agricultural machinery, construction machinery, small mobile power stations and chariots around the world are powered by internal combustion engines.
Marine merchant ships, inland river ships and conventional ships, as well as some small aircraft are also propelled by internal combustion engines.
The number of internal combustion engines ranks first in the world's power machinery and occupies a very important position in human activities.
Piston internal combustion engine originated from powder explosion to gain power, but it was not successful because the powder combustion was difficult to control.
1794, streeter, an Englishman, put forward the concept of mixing fuel with air for the first time.
1833, British Wright put forward the design of directly using combustion pressure to push the piston to do work.
After that, people put forward various internal combustion engine schemes, but they were not put into practice until the middle of the nineteenth century.
Until 1860, the Frenchman Lenoir imitated the structure of the steam engine and designed and manufactured the first practical gas engine.
This is an internal combustion engine with no compression, electric ignition and gas ignition.
Lenoir first adopted elastic piston rings in internal combustion engines.
The thermal efficiency of this gas turbine is about 4%.
Barnett of Britain once advocated compressing combustible mixture before ignition, and then someone wrote an article to discuss the important role of compressing combustible mixture, and pointed out that compression can greatly improve the efficiency of lenoir internal combustion engine.
1862, French scientist Rosa theoretically analyzed the thermal process of internal combustion engine, and put forward the requirement of improving the efficiency of internal combustion engine, which is the earliest four-stroke working cycle.
1876, the German inventor Otto successfully manufactured the first reciprocating piston, single cylinder, horizontal, 3.2 kW (4.4 HP) four-stroke internal combustion engine, still using gas as fuel, using flame ignition, rotating speed 156.7 rpm, compression ratio 2.66 and thermal efficiency 14.
At that time, both power and thermal efficiency were the highest.
Otto internal combustion engine has been popularized and its performance is improving.
1880, the single machine power reached1~15kw (15 ~ 20hp), and 1893 increased to 150 kW.
With the increase of compression ratio, the thermal efficiency also increases. The thermal efficiency in 1886 is 15.5%, and it has reached 20 ~ 26% in 1897.
188 1 year, British engineer Clark successfully developed the first two-stroke gas engine and exhibited it at the Paris Expo.
With the development of petroleum, people pay attention to gasoline and diesel which are easier to transport and carry than gas. First of all, volatile gasoline has been tried.
1883, Daimler Company of Germany successfully manufactured the first vertical gasoline engine, which is characterized by light weight and high speed.
At that time, the speed of other internal combustion engines did not exceed 200 rpm, but jumped to 800 rpm, which was especially suitable for the requirements of transportation machinery.
From1885 to1886, the gasoline engine successfully operated as the automobile power, which greatly promoted the development of the automobile.
At the same time, the development of automobile promotes the improvement and improvement of gasoline engine.
Soon, the gasoline engine was used as the power of the ship again.
1892, inspired by the dust explosion in the flour mill, German engineer Diesel imagined that the air sucked into the cylinder would be highly compressed to make its temperature exceed the self-ignition temperature of the fuel, and then the fuel would be blown into the cylinder with high-pressure air to ignite it.
His first compression-ignition internal combustion engine (diesel engine) was successfully developed in 1897, which opened up a new road for the development of internal combustion engines.
The diesel engine began to try to make the internal combustion engine realize Carnot cycle in order to obtain the highest thermal efficiency, but in fact it realized approximate isobaric combustion with a thermal efficiency of 26%.
The advent of compression ignition internal combustion engine has aroused great interest in the world machinery industry, and compression ignition internal combustion engine is also named diesel engine after the inventor.
This kind of internal combustion engine will use diesel as fuel in the future, so it is also called diesel engine.
1898 diesel engine was first used for stationary generator sets, 1903 was used as power for merchant ships, 1904 was installed on ships, 19 13 was the first diesel locomotive driven by diesel engine, and it began to be used in automobiles and agriculture around 1920.
Long before the birth of reciprocating piston internal combustion engine, people tried to make rotary piston internal combustion engine, but all failed.
It was not until 1954 that Wankel, a German engineer, solved the sealing problem and developed a rotary piston engine called Wankel engine in 1957.
It has an approximately triangular rotating piston, which rotates in a cylinder with a specific profile and works according to the Otto cycle.
This kind of engine has the advantages of high power, small volume, small vibration, stable operation, simple structure and convenient maintenance. However, due to its poor fuel economy, low low-speed torque and unsatisfactory exhaust performance, it is only used on individual vehicles.
Internal combustion engine is famous for its high thermal efficiency, compact structure, strong maneuverability and simple operation and maintenance.
100 years, the great vitality of internal combustion engines has been enduring.
At present, the number of internal combustion engines in the world greatly exceeds that of any other heat engine and occupies a very important position in the national economy.
Modern internal combustion engine has become the most important, consuming and widely used thermal machinery.
Of course, the internal combustion engine also has many shortcomings, mainly: high fuel requirements, can not directly burn inferior fuel and solid fuel; Due to intermittent ventilation and manufacturing difficulties, the power increase of single machine is limited. The maximum power of modern internal combustion engines is generally less than 40 thousand kilowatts, while the single power of steam engines can be as high as several hundred thousand kilowatts. The internal combustion engine cannot be reversed; The noise of internal combustion engine and harmful components in exhaust gas especially pollute the environment.
It can be said that the development history of internal combustion engine in the past hundred years is a history of continuous innovation and challenges to overcome these shortcomings.
The development of internal combustion engine has a history of about one and a half centuries.
Like other sciences, every progress of internal combustion engine is a summary and generalization of human production practice experience.
The invention of internal combustion engine began with the research and improvement of piston steam engine.
In the history of its development, we should especially mention German Otto and Dissel. It is they who put forward the perfect Otto cycle and Diesel cycle for the working cycle of internal combustion engine on the basis of summarizing countless practical experiences of predecessors, which made the practice and creative activities of countless people get a scientific summary and a qualitative leap. They inherited, developed, summarized and improved the superficial, purely empirical and disorderly experience of their predecessors.
Reciprocating piston internal combustion engine
There are many kinds of reciprocating piston internal combustion engines, and the main classification methods are as follows: according to the different fuels used, they are divided into gasoline engines, diesel engines, kerosene engines and gas engines (including various gas internal combustion engines). According to the different number of strokes in each working cycle, it is divided into four strokes and two strokes; According to different ignition methods, it can be divided into ignition type and compression ignition type; According to different cooling methods, it can be divided into water cooling and air cooling; According to the different arrangement forms of cylinders, they are divided into in-line type, V-type, opposite type and star type. According to the number of cylinders, it can be divided into single-cylinder internal combustion engine and multi-cylinder internal combustion engine. According to the different uses of internal combustion engines, they are divided into automobile, agricultural, locomotive, marine and fixed use.
This article will mainly introduce the development of gas engines, gasoline engines and diesel engines to you.
The earliest internal combustion engine-gas engine
The earliest internal combustion engine was a gas engine with gas as fuel.
1860, the French inventor Lionel made the first practical internal combustion engine (single cylinder, two-stroke, uncompressed, electric ignition gas engine, output power 0.74- 1.47 kW, speed 100r/min, thermal efficiency 4%).
French engineer de Rocha realized that in order to improve the thermal efficiency of internal combustion engine as much as possible, it is necessary to reduce the cooling area of each cylinder volume as much as possible, expand the piston as soon as possible, and expand the range (stroke) as long as possible.
On this basis, he put forward the famous four-stroke cycle of constant volume combustion in 1862: intake, compression, combustion expansion and exhaust.
1876, Otto, a German, made the first four-stroke reciprocating piston internal combustion engine (single cylinder, horizontal, gas as fuel, power about 2.2 1KW, 180r/min).
On this engine, Otto added a flywheel to make it run smoothly, lengthened the air intake and improved the cylinder head to make the mixture fully formed.
This is a very successful engine, and its thermal efficiency is twice that of the steam engine at that time.
Otto integrated the three key technical ideas of internal combustion, compressed gas and four stroke, which made this internal combustion engine have a series of advantages such as high efficiency, small size, light weight and high power.
At the 1878 Paris World Expo, it was praised as "the greatest achievement of power machine since Watt".
The four-stroke cycle of constant volume combustion is realized by Otto cycle, also known as Otto cycle.
Although gas engines have great advantages over steam engines, they still can't meet the requirements of high speed and portability in the case of socialized mass production.
Because it uses gas as fuel, it needs a huge gas generator and pipeline system.
Moreover, the calorific value of the gas is low (about1.75×107 ~ 2.09×107j/m3), so the gas turbine has a slow rotating speed and a small specific power.
By the second half of19th century, with the rise of petroleum industry, it has become an inevitable trend to use petroleum products instead of natural gas as fuel.