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Hub AI
Diesel engine AI simulator
(@Diesel engine_simulator)
Hub AI
Diesel engine AI simulator
(@Diesel engine_simulator)
Diesel engine
The diesel engine, named after the German engineer Rudolf Diesel, is an internal combustion engine in which ignition of diesel fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is called a compression-ignition engine (or CI engine). This contrasts with engines using spark plug-ignition of the air-fuel mixture, such as a petrol engine (gasoline engine) or a gas engine (using a gaseous fuel like natural gas or liquefied petroleum gas).
Diesel engines work by compressing only air, or air combined with residual combustion gases from the exhaust (known as exhaust gas recirculation, "EGR"). Air is inducted into the chamber during the intake stroke, and compressed during the compression stroke. This increases air temperature inside the cylinder so that atomised diesel fuel injected into the combustion chamber ignites. The torque a diesel engine produces is controlled by manipulating the air-fuel ratio (λ); instead of throttling the intake air, the diesel engine relies on altering the amount of fuel that is injected, and thus the air-fuel ratio is usually high.[citation needed]
The diesel engine has the highest thermal efficiency (see engine efficiency) of any practical internal or external combustion engine due to its very high expansion ratio and inherent lean burn, which enables heat dissipation by excess air. A small efficiency loss is also avoided compared with non-direct-injection gasoline engines, as unburned fuel is not present during valve overlap, and therefore no fuel goes directly from the intake/injection to the exhaust. Low-speed diesel engines (as used in ships and other applications where overall engine weight is relatively unimportant) can reach effective efficiencies of up to 55%. The combined cycle gas turbine (Brayton and Rankine cycle) is a combustion engine that is more efficient than a diesel engine, but due to its mass and dimensions, is unsuitable for many vehicles, including watercraft and some aircraft. The world's largest diesel engines put in service are 14-cylinder, two-stroke marine diesel engines; they produce a peak power of almost 100 MW each.
Diesel engines may be designed with either two-stroke or four-stroke combustion cycles. They were originally used as a more efficient replacement for stationary steam engines. Since the 1910s, they have been used in submarines and ships. Use in locomotives, buses, trucks, heavy equipment, agricultural equipment and electricity generation plants followed later. In the 1930s, they slowly began to be used in some automobiles. Since the 1970s energy crisis, demand for higher fuel efficiency has resulted in most major automakers, at some point, offering diesel-powered models, even in very small cars. According to Konrad Reif (2012), the EU average for diesel cars at the time accounted for half of newly registered cars. However, air pollution and overall emissions are more difficult to control in diesel engines compared to gasoline engines, so the use of diesel engines in the US is now largely relegated to larger on-road and off-road vehicles.
Though aviation has traditionally avoided using diesel engines, aircraft diesel engines have become increasingly available in the 21st century. Since the late 1990s, for various reasons—including diesel's inherent advantages over gasoline engines, but also for recent issues peculiar to aviation—development and production of diesel engines for aircraft has surged, with over 5,000 such engines delivered worldwide between 2002 and 2018, particularly for light airplanes and unmanned aerial vehicles.
In 1878, Rudolf Diesel, who was a student at the "Polytechnikum" in Munich, attended the lectures of Carl von Linde. Linde explained that steam engines are capable of converting just 6–10% of the heat energy into work, but that the Carnot cycle allows conversion of much more of the heat energy into work by means of isothermal change in condition. According to Diesel, this ignited the idea of creating a highly efficient engine that could work on the Carnot cycle. Diesel was also introduced to a fire piston, a traditional fire starter using rapid adiabatic compression principles which Linde had acquired from Southeast Asia. After several years of working on his ideas, Diesel published them in 1893 in the essay Theory and Construction of a Rational Heat Motor.
Diesel was heavily criticised for his essay, but only a few found the mistake that he made; his rational heat motor was supposed to utilise a constant temperature cycle (with isothermal compression) that would require a much higher level of compression than that needed for compression ignition. Diesel's idea was to compress the air so tightly that the temperature of the air would exceed that of combustion. However, such an engine could never perform any usable work. In his 1892 US patent (granted in 1895) #542846, Diesel describes the compression required for his cycle:
pure atmospheric air is compressed, according to curve 1 2, to such a degree that, before ignition or combustion takes place, the highest pressure of the diagram and the highest temperature are obtained-that is to say, the temperature at which the subsequent combustion has to take place, not the burning or igniting point. To make this more clear, let it be assumed that the subsequent combustion shall take place at a temperature of 700°. Then in that case the initial pressure must be sixty-four atmospheres, or for 800° centigrade the pressure must be ninety atmospheres, and so on. Into the air thus compressed is then gradually introduced from the exterior finely divided fuel, which ignites on introduction, since the air is at a temperature far above the igniting-point of the fuel. The characteristic features of the cycle according to my present invention are therefore, increase of pressure and temperature up to the maximum, not by combustion, but prior to combustion by mechanical compression of air, and there upon the subsequent performance of work without increase of pressure and temperature by gradual combustion during a prescribed part of the stroke determined by the cut-oil.
Diesel engine
The diesel engine, named after the German engineer Rudolf Diesel, is an internal combustion engine in which ignition of diesel fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is called a compression-ignition engine (or CI engine). This contrasts with engines using spark plug-ignition of the air-fuel mixture, such as a petrol engine (gasoline engine) or a gas engine (using a gaseous fuel like natural gas or liquefied petroleum gas).
Diesel engines work by compressing only air, or air combined with residual combustion gases from the exhaust (known as exhaust gas recirculation, "EGR"). Air is inducted into the chamber during the intake stroke, and compressed during the compression stroke. This increases air temperature inside the cylinder so that atomised diesel fuel injected into the combustion chamber ignites. The torque a diesel engine produces is controlled by manipulating the air-fuel ratio (λ); instead of throttling the intake air, the diesel engine relies on altering the amount of fuel that is injected, and thus the air-fuel ratio is usually high.[citation needed]
The diesel engine has the highest thermal efficiency (see engine efficiency) of any practical internal or external combustion engine due to its very high expansion ratio and inherent lean burn, which enables heat dissipation by excess air. A small efficiency loss is also avoided compared with non-direct-injection gasoline engines, as unburned fuel is not present during valve overlap, and therefore no fuel goes directly from the intake/injection to the exhaust. Low-speed diesel engines (as used in ships and other applications where overall engine weight is relatively unimportant) can reach effective efficiencies of up to 55%. The combined cycle gas turbine (Brayton and Rankine cycle) is a combustion engine that is more efficient than a diesel engine, but due to its mass and dimensions, is unsuitable for many vehicles, including watercraft and some aircraft. The world's largest diesel engines put in service are 14-cylinder, two-stroke marine diesel engines; they produce a peak power of almost 100 MW each.
Diesel engines may be designed with either two-stroke or four-stroke combustion cycles. They were originally used as a more efficient replacement for stationary steam engines. Since the 1910s, they have been used in submarines and ships. Use in locomotives, buses, trucks, heavy equipment, agricultural equipment and electricity generation plants followed later. In the 1930s, they slowly began to be used in some automobiles. Since the 1970s energy crisis, demand for higher fuel efficiency has resulted in most major automakers, at some point, offering diesel-powered models, even in very small cars. According to Konrad Reif (2012), the EU average for diesel cars at the time accounted for half of newly registered cars. However, air pollution and overall emissions are more difficult to control in diesel engines compared to gasoline engines, so the use of diesel engines in the US is now largely relegated to larger on-road and off-road vehicles.
Though aviation has traditionally avoided using diesel engines, aircraft diesel engines have become increasingly available in the 21st century. Since the late 1990s, for various reasons—including diesel's inherent advantages over gasoline engines, but also for recent issues peculiar to aviation—development and production of diesel engines for aircraft has surged, with over 5,000 such engines delivered worldwide between 2002 and 2018, particularly for light airplanes and unmanned aerial vehicles.
In 1878, Rudolf Diesel, who was a student at the "Polytechnikum" in Munich, attended the lectures of Carl von Linde. Linde explained that steam engines are capable of converting just 6–10% of the heat energy into work, but that the Carnot cycle allows conversion of much more of the heat energy into work by means of isothermal change in condition. According to Diesel, this ignited the idea of creating a highly efficient engine that could work on the Carnot cycle. Diesel was also introduced to a fire piston, a traditional fire starter using rapid adiabatic compression principles which Linde had acquired from Southeast Asia. After several years of working on his ideas, Diesel published them in 1893 in the essay Theory and Construction of a Rational Heat Motor.
Diesel was heavily criticised for his essay, but only a few found the mistake that he made; his rational heat motor was supposed to utilise a constant temperature cycle (with isothermal compression) that would require a much higher level of compression than that needed for compression ignition. Diesel's idea was to compress the air so tightly that the temperature of the air would exceed that of combustion. However, such an engine could never perform any usable work. In his 1892 US patent (granted in 1895) #542846, Diesel describes the compression required for his cycle:
pure atmospheric air is compressed, according to curve 1 2, to such a degree that, before ignition or combustion takes place, the highest pressure of the diagram and the highest temperature are obtained-that is to say, the temperature at which the subsequent combustion has to take place, not the burning or igniting point. To make this more clear, let it be assumed that the subsequent combustion shall take place at a temperature of 700°. Then in that case the initial pressure must be sixty-four atmospheres, or for 800° centigrade the pressure must be ninety atmospheres, and so on. Into the air thus compressed is then gradually introduced from the exterior finely divided fuel, which ignites on introduction, since the air is at a temperature far above the igniting-point of the fuel. The characteristic features of the cycle according to my present invention are therefore, increase of pressure and temperature up to the maximum, not by combustion, but prior to combustion by mechanical compression of air, and there upon the subsequent performance of work without increase of pressure and temperature by gradual combustion during a prescribed part of the stroke determined by the cut-oil.
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