Internal combustion engines come in various types, but have certain family resemblances, and thus share many common types of components.
Video Component parts of internal combustion engines
Combustion chamber
The internal combustion engine can contain a number of combustion chambers (cylinders), with numbers between one and twelve common, though as many as 36 (Lycoming R-7755) have been used. Having more cylinders in the engine produces two potential benefits: first, the engine can have a larger displacement with smaller individual reciprocating masses, ie the mass of each piston can be less making the engine run more smoothly as the engine tends to vibrate. as a result of the piston moving up and down. Doubling the number of cylinders of the same size will double the torque and power. The downside to having more pistons is that the engine will tend to weigh more and generate more internal friction as more pistons are rubbing against the inside of their cylinders. This tends to reduce fuel efficiency and robs the engine of some of its power. For high-performance gasoline engines using current materials and technologies, such as engines found in modern cars, there appears to be about 10 or 12 cylinders after the addition of a cylinder to an overall loss of performance and efficiency. Although, exceptions such as the W16 engine from Volkswagen exist.
- Most car engines have four to eight cylinders, with some high performing cars having ten, 12- or even 16, and some very small cars and trucks have two or three. In previous years, some fairly large cars like the DKW and Saab 92, had a two-cylinder or two-stroke engine.
- Radial plane engines have three to 28 cylinders; examples include the small Kinner B-5 and Pratt & amp; Whitney R-4360. Larger samples are constructed as multiple lines. Since each row contains an odd number of cylinders, to provide the same startup sequence for a four-step engine, even numbers indicate two or four row engines. The biggest one is the Lycoming R-7755 with 36 cylinders (four rows of nine cylinders), but does not go into production.
- Motorcycles typically have one to four cylinders, with some high-performance models having six; though, some 'new stuff' exists with 8, 10, or 12.
- Snowmobiles Usually have one to four cylinders and can be either 2-stroke or 4-stroke, usually in in-line configuration; However, there are some more new things that exist with V-4 engine
- Small portable appliances such as chainsaws, generators, and the most common domestic mower have one cylinder, but a two-cylinder saw is present.
- Large, reversible two-cycle marine recycling has a minimum of three to more than ten cylinders. Cargo diesel locomotives typically have about 12 to 20 cylinders due to space limitations, as larger cylinders take up more space (volume) per kwh, because the average piston speed limit is less than 30 ft/sec on machines lasting more than 40,000 hours under full force.
Maps Component parts of internal combustion engines
Ignition System
The ignition system of the internal combustion engine depends on the type of engine and fuel used. Gasoline engines are typically turned on by a timely spark, and diesel engines with compressed heating. Historically, outside the fire and hot tube systems were used, see the hot bulb machine.
Spark
In an ignition engine, the mixture is ignited by an electric spark from the spark plug - a very precise time is controlled. Almost all gasoline engines are of this type. Diesel engine time is precisely controlled by pressure pump and injector. The normal pairing distance between the spark plugs is 1mm, and the tension is 3000v under normal atmospheric conditions.
Compression
Ignition occurs because the temperature of the fuel/air mixture is taken above its autoignition temperature, due to the heat generated by compressed air during stroke compression. Most of the compression ignition engines are diesel where the fuel is mixed with air after the air reaches the ignition temperature. In this case, the time comes from the fuel injection system. A very small model engine with simplicity and weight is more important than the fuel cost of using a combustible fuel (a mixture of kerosene, ether, and lubricant) and compression that can be adjusted to control the ignition time to start and run.
Ignition Time
For reciprocating engines, the point in the cycle in which the fuel-oxidator mixture is switched has a direct effect on the efficiency and output of ICE. The ideal thermodynamics of the idealized Carnot heat engine tells us that ICE is most efficient if most combustion takes place at high temperatures, due to compression - near the top die center. The velocity of the fire front is directly influenced by the compression ratio, the fuel mix temperature, and the octane or cetane value of the fuel. The Leaner mixture and lower mixture pressure will burn more slowly and thus require more sophisticated ignition times. It is important to have combustion propagated by thermal flame front (deflagration), not by shock waves. The combustion culture by the shock wave is called detonation and, in the machine, is also known as ping or machine knock.
So at least in a gasoline burner, ignition timing is largely a compromise between "backward" sparks - which provide greater efficiency with high-octane fuel - and earlier "sophisticated" sparks that avoid detonating with the fuel used. For this reason, supporters of high-performance diesel cars, such as Gale Banks, believe it
Only so far you can use an air-sprayed machine on 91-octane gasoline. In other words, it's fuel, gasoline, which has become a limiting factor.... While turbocharging has been applied to gasoline and diesel engines, only a limited boost can be added to the gasoline engine before the octane level of fuel is again a problem. With diesel, increasing pressure is essentially unlimited. It is literally possible to run a boost as much as the machine will physically stand before it broke. Consequently, the engine designer has realized that the diesel engine is capable of producing much more power and torque than a comparable gasoline engine.
Fuel system
Fuel burns faster and more efficiently when they present a large surface area for oxygen in the air. Liquid fuels should be atomized to create a mixture of air fuel, traditionally this is done with a carburetor in gasoline engines and with fuel injectors in diesel engines. Most modern gasoline engines now use fuel injection too - although the technology is very different. While diesel should be injected at the correct point in the engine cycle, no such precision is required in the gasoline engine. However, the lack of lubricants in gasoline means that the injector itself must be more sophisticated.
Carburetor
A simpler reciprocating engine continues to use the carburetor to supply fuel into the cylinder. Although carburetor technology in the car achieved a very high level of sophistication and accuracy, from the mid-1980s lost the cost and flexibility for fuel injectors. Simple carburetor forms are still widely used in small machines such as lawn mowers and more sophisticated forms still used in small motorcycles.
Fuel injection
The larger gasoline engines used in cars have largely moved to fuel injection systems (see Gasoline Direct Injection). Diesel engines always use a fuel injection system because the injection time begins and controls the combustion.
The Autogas engine uses a fuel injection system or an open or closed loop carburetor.
Fuel pump
Most internal combustion engines now require fuel pumps. Diesel engines use all-mechanical precision pumping systems that deliver direct-injection into the combustion chamber, requiring high delivery pressure to overcome the pressure of the combustion chamber. Fuel injection of gasoline sends to the inlet at atmospheric pressure (or below) and time is not involved, this pump is usually electrically driven. Gas turbines and rocket engines use electrical systems.
More
Other internal combustion engines such as jet engines and rocket engines use a variety of fuel delivery methods including crashing jets, gas/liquid shear, preburner and others.
Oxidiser-Air input system
Some engines such as solid rockets have oxidizers already inside the combustion chamber but in many cases for burning, continuous oxidizing supplies must be supplied to the combustion chamber.
Machine naturally aspirated
When the air is used with a piston engine, it can only suck it when the piston increases the volume of space. However, this provides a maximum of 1 atmospheric pressure difference in the inlet valve, and at high engine speed the resulting airflow can limit the output potential.
Supercharger and turbocharger
Supercharger is a system of "forced induction" which uses a compressor powered by the engine shaft that pushes air through the engine valve to achieve a higher flow. When this system is used, the maximum absolute pressure on the inlet valve is usually about 2 times atmospheric or more pressure.
Turbochargers are another type of forced induction system that has compressors powered by a gas turbine that flows from the exhaust gases of the engine.
Turbochargers and superchargers are very useful in the highlands and are often used in aircraft engines.
The channel jet engine uses the same basic system, but avoid the piston engine, and replace it with a burner only.
Fluid
In a liquid rocket engine, the oxidizer comes in liquid form and must be sent at high pressure (typically 10-230 bar or 1-23 MPa) into the combustion chamber. This is usually achieved by using centrifugal pumps supported by gas turbines - configurations known as turbopumps, but can also be fed under pressure.
Section
For four-stroke engines, the main parts of the machine include crankshaft (purple), connecting rod (orange), one camshaft or more (red and blue), and valve. For a two-stroke engine, there may be only an outlet and fuel inlet instead of a valve system. In both types of machines there are one or more cylinders (gray and green), and for every cylinder there are spark plugs (darker-gray, only gasoline engines), pistons (yellow), and crankpin (purple). The single stroke of the cylinder by the piston in upward or downward movement is known as a stroke. The downward stroke that occurs immediately after the fuel-air mixture passes from the carburetor or fuel injector to the cylinder (where it is lit) is also known as the stroke power.
The Wankel machine has an orbiting triangle rotor in the epitrochoidal chamber (figure 8) around the eccentric shaft. Four phases of operation (intake, compression, power, and disposal) take place in a room that effectively moves, variable volume.
Valves
All four-stroke internal combustion engines use valves to control the entry of fuel and air into the combustion chamber. The two-step machine uses a port in a cylindrical hole, covered and found by a piston, although there are variations such as a flue valve.
Piston engine valve
In piston engines, the valves are grouped into an 'entrance valve' which receives the entry of fuel and air and the 'exit valve' which allows the flue gas to escape. Each valve is open once per cycle and one that is subjected to extreme acceleration is held closed by a spring normally opened by a rod running on a rotating shaft with a crankshaft of the engine.
Control valve
Continuous combustion engines - as well as piston engines - usually have a valve that opens and closes to receive fuel and/or air at startup and shutdown. Some feather valves to regulate the flow to control the power or engine speed as well.
Exhaust system
The internal combustion engine must effectively manage the discharge of the cooled combustion gas from the engine. Exhaust systems often contain devices to control chemical pollution and noise. In addition, for cyclic combustion engines, the exhaust system is often tuned to increase the discharge of the combustion chamber. The majority of the exhaust also has a system to prevent heat reaching places that will face damage from it like heat-sensitive components, often referred to as Exhaust Heat Management.
For internal jet propulsion combustion engines, the 'exhaust system' takes the form of a high-speed nozzle, which generates thrust for the engine and forms a polymerized gas jet that names its engine.
Cooling system
Burning generates a lot of heat, and some of this goes to the machine wall. Failure will occur if the engine body is allowed to reach too high a temperature; whether the machine will fail physically, or the used lubricant will decrease to the point where they no longer protect the machine. Lubricants must be clean because dirty lubrication can cause the formation of sludge in the machine.
Cooling systems typically use air conditioning or liquid (usually water), while some very hot machines use radiant cooling (especially some rocket engines). Some high-altitude rocket engines use ablative cooling, where the walls gradually erode in a controlled manner. The rocket in particular can use regenerative cooling, which uses fuel to cool the solid parts of the engine.
Piston
piston is a component of engine reciprocating. It lies inside the cylinder and is made gasproof by a piston ring. The goal is to transfer the power from extending the gas in the cylinder to the crankshaft via the piston rod and/or connecting rod. In a two-stroke piston engine it also acts as a valve by closing and uncovering ports on the cylinder wall.
Pushing the nozzle
To form a jet engine from an internal combustion engine, the propellant nozzle is present. It takes high temperature, high pressure, and expands and cools it. The exhaust leaves the nozzle going higher and gives a boost, and constricts the flow from the engine and increases the pressure on the rest of the engine, giving a larger boost to the exhaust mass coming out.
Crankshaft
Most internal combustion reciprocating engines end up with rotating shafts. This means that the piston linear motion must be converted into rotation. This is usually achieved by the crankshaft.
Crazy Wheel
The crazy wheel is a disc or wheel attached to the crank, forming an inertia mass that stores the rotational energy. In a machine with only one cylinder, a flywheel is essential to drain energy from the power stroke to the next compression step. Wheel wheels are present in most reciprocating engines to smooth the delivery of power at each crank and in most automotive engines also install gear rings for starters. Rotational inertia on the flywheel also allows lower speeds lowered lower and also improves smoothness at idle. The crazy wheel can also perform part of the system balancing and by itself becomes unbalanced, although most machines will use a neutral balance for the flywheel, allowing it to be balanced in separate operations. The crazy wheel is also used as a mounting for clutch or torque converter in most automotive applications.
Starter system
All internal combustion engines require some form of system to make it operate. Most piston engines use starter motors powered by the same battery as running the rest of the electrical system. Large jet engines and gas turbines begin with compressed air motors directed to one of the driveshafts engines. Compressed air can be supplied from other machines, units on the ground or by APU aircraft. Small internal combustion engines often begin by pulling the rope. Motorcycles of all sizes traditionally begin, though all but the smallest ones now begin electrically. Large stationary and marine engines can be started with compressed air injection into a cylinder - or sometimes with a cartridge. Direct starts referring to the help of other batteries (usually when the battery is installed is released), while the bump begins to refer to alternative methods starting with the application of some external forces, for example rolling down the hill.
Heat protection system
These systems often work in combination with engine cooling and exhaust systems. A heat shield is required to prevent engine heat from damaging heat-sensitive components. The majority of older cars use simple steel thermal protectors to reduce thermal and convective radiation. Now the most common for modern cars is to use aluminum heat shield which has a lower density, can be easily formed and does not corrode just like steel. High-performance vehicles begin to use ceramic heat shields as these can withstand much higher temperatures as well as further reductions in heat transfer.
Lubrication System
Internal combustion engines require lubrication in operations that move parts gliding smoothly with each other. The subject of insufficient lubrication of machine parts to metal-to-metal contact, friction, heat buildup, rapid wear often culminates in parts that become welded together together eg. piston in the cylinder. Big end bearings that take up time will cause the connecting rod to break and poke through the crankcase.
Several types of system lubrication are used. A simple two-step machine is lubricated with oil mixed into the fuel or injected into the induction stream as a spray. Initial stationary and slow-speed marine engines lubricated by gravity from a small space similar to those used on steam engines at the time - with the tender engine recharging it as needed. Since the engine is adapted for automotive and aircraft use, the need for a high power-to-weight ratio leads to increased speed, higher temperatures, and greater pressure on bearings which in turn requires pressure lubrication for crank bearings and connecting rod journals. This is provided either by direct lubrication of the pump, or indirectly by oil jets directed at the pickup cups at the end of the connecting rod which has the advantage of providing higher pressure when engine speed increases.
System control
Most machines require one or more systems to start and shut down the engine and to control parameters such as power, speed, torque, pollution, combustion temperatures, and efficiency and to stabilize the engine from an operation mode that can cause self-destruction such as pre-ignition. Such a system can be referred to as a machine control unit.
Many current control systems are digital, and are often called FADEC systems (Electronic Digital Authority Control).
Diagnostic system
Engine On Board Diagnostics (also known as OBD) is a computerized system that enables the electronic diagnosis of a vehicle's powerplant. The first generation, known as OBD1 , was introduced 10 years after the US Congress passed the Clean Air Act in 1970 as a way to monitor vehicle fuel injection systems. OBD2 , a second-generation onboard computer diagnostic, codified and recommended by the California Air Resources Board in 1994 and became a compulsory equipment in all vehicles sold in the United States in 1996.
See also
- jet engine
- piston machine
References
Source of the article : Wikipedia
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