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Hopper cooling is a simple form of water cooling used for small stationary engines. The defining feature of hopper cooling, amongst other water-cooled engines, is that there is no radiator. Cooling water is heated by the engine and evaporates from the surface of the hopper as steam | https://huggingface.co/datasets/fmars/wiki_stem |
An intercooler is a heat exchanger used to cool a gas after compression. Often found in turbocharged engines, intercoolers are also used in air compressors, air conditioners, refrigeration and gas turbines.
Internal combustion engines
Most commonly used with turbocharged engines, an intercooler is used to counteract the heat of compression and heat soak in the pressurised intake air | https://huggingface.co/datasets/fmars/wiki_stem |
Oil cooling is the use of engine oil as a coolant, typically to remove surplus heat from an internal combustion engine. The hot engine transfers heat to the oil which then usually passes through a heat-exchanger, typically a type of radiator known as an oil cooler. The cooled oil flows back into the hot object to cool it continuously | https://huggingface.co/datasets/fmars/wiki_stem |
Radiators are heat exchangers used for cooling internal combustion engines, mainly in automobiles but also in piston-engined aircraft, railway locomotives, motorcycles, stationary generating plant or any similar use of such an engine.
Internal combustion engines are often cooled by circulating a liquid called engine coolant through the engine block, and cylinder head where it is heated, then through a radiator where it loses heat to the atmosphere, and then returned to the engine. Engine coolant is usually water-based, but may also be oil | https://huggingface.co/datasets/fmars/wiki_stem |
Siamesed cylinders are engine cylinders arranged in such a way that they have no channels between them to allow water or other coolant to circulate. Cylinders are generally arranged in this manner when the engine block is of limited size or when stability of the cylinder bores is of concern, such as in racing engines. The advantage is that the engine block will be reduced in size, or the bore can be increased in size | https://huggingface.co/datasets/fmars/wiki_stem |
Water cooling is a method of heat removal from components and industrial equipment. Evaporative cooling using water is often more efficient than air cooling. Water is inexpensive and non-toxic; however, it can contain impurities and cause corrosion | https://huggingface.co/datasets/fmars/wiki_stem |
Waterless coolant is a glycol-based liquid substance that does not contain water. Its boiling point of 191 °C (375 °F) is higher than that of water-based coolants and it resists the formation of corrosion. The substance was invented to circumvent the problems of vaporizing water | https://huggingface.co/datasets/fmars/wiki_stem |
Two-stroke oil (also referred to as two-cycle oil, 2-cycle oil, 2T oil, or 2-stroke oil) is a special type of motor oil intended for use in crankcase compression two-stroke engines, typical of small gasoline-powered engines.
Use
Unlike a four-stroke engine, the crankcase of which is closed except for its ventilation system, a two-stroke engine uses the crankcase as part of the induction tract, so oil must be mixed with gasoline to be distributed throughout the engine for lubrication. The resultant mix is referred to as premix or petroil | https://huggingface.co/datasets/fmars/wiki_stem |
Automatic lubrication (also called autolube or auto-lube) refers to a lubrication system on a two-stroke engine, in which the oil is automatically mixed with fuel and manual oil-fuel pre-mixing is not necessary. The oil is contained in a reservoir that connects to a small oil pump in the engine, which needs to be periodically refilled.
This system is commonly used for motorcycles as it eliminates the need of pre-mixing fuel and two-stroke oil | https://huggingface.co/datasets/fmars/wiki_stem |
A dry-sump system is a method to manage the lubricating motor oil in four-stroke and large two-stroke piston driven internal combustion engines. The dry-sump system uses two or more oil pumps and a separate oil reservoir, as opposed to a conventional wet-sump system, which uses only the main sump (U. S | https://huggingface.co/datasets/fmars/wiki_stem |
Motor oil, engine oil, or engine lubricant is any one of various substances used for the lubrication of internal combustion engines. They typically consist of base oils enhanced with various additives, particularly antiwear additives, detergents, dispersants, and, for multi-grade oils, viscosity index improvers. The main function of motor oil is to reduce friction and wear on moving parts and to clean the engine from sludge (one of the functions of dispersants) and varnish (detergents) | https://huggingface.co/datasets/fmars/wiki_stem |
Oil analysis (OA) is the laboratory analysis of a lubricant's properties, suspended contaminants, and wear debris. OA is performed during routine predictive maintenance to provide meaningful and accurate information on lubricant and machine condition. By tracking oil analysis sample results over the life of a particular machine, trends can be established which can help eliminate costly repairs | https://huggingface.co/datasets/fmars/wiki_stem |
Oil pressure is an important factor in the longevity of most internal combustion engines. With a forced lubrication system (invented by Frederick Lanchester), oil is picked up by a positive displacement oil pump and forced through oil galleries (passageways) into bearings, such as the main bearings, big end bearings and camshaft bearings or balance shaft bearings. Other components such as cam lobes and cylinder walls are lubricated by oil jets | https://huggingface.co/datasets/fmars/wiki_stem |
The oil pump is an internal combustion engine part that circulates engine oil under pressure to the rotating bearings, the sliding pistons and the camshaft of the engine. This lubricates the bearings, allows the use of higher-capacity fluid bearings and also assists in cooling the engine.
As well as its primary purpose for lubrication, pressurized oil is increasingly used as a hydraulic fluid to power small actuators | https://huggingface.co/datasets/fmars/wiki_stem |
A ring oiler or oil ring is a form of oil-lubrication system for bearings.
Ring oilers were used for medium-speed applications with moderate loads, during the first half of the 20th century. These represented the later years of the stationary steam engine, and the beginnings of the high-speed steam engine, the internal combustion oil engine and electrical generating equipment | https://huggingface.co/datasets/fmars/wiki_stem |
A total-loss oiling system is an engine lubrication system whereby oil is introduced into the engine, and then either burned or ejected overboard. Now rare in four-stroke engines, total loss oiling is still used in many two-stroke engines.
Steam engines
Steam engines used many separate oil boxes, dotted around the engine | https://huggingface.co/datasets/fmars/wiki_stem |
A turbo timer is a device designed to keep an automotive engine running for a pre-specified period in order to automatically execute the cool-down period required to prevent premature turbo wear and failure. After a period of driving when a turbocharger has been working hard, it is important to let the engine run at idle speed for a period, allowing the compressor assembly to cool from the lower gas temperatures in both the exhaust and intake tracts. At the same time the lubricating oil from the engine is able to circulate properly so the turbine won't burn the lubricating oil that would otherwise be trapped within the charger with the turbine rotating at high speed | https://huggingface.co/datasets/fmars/wiki_stem |
Within piston engines, a wet sump is part of a lubrication system whereby the crankcase sump is used as an integral oil reservoir. An alternative system is the dry sump, whereby oil is pumped from a shallow sump into an external reservoir. Piston engines are lubricated by oil which is pumped into various bearings, and thereafter allowed to drain to the base of the engine under gravity | https://huggingface.co/datasets/fmars/wiki_stem |
An exhaust system is used to guide reaction exhaust gases away from a controlled combustion inside an engine or stove. The entire system conveys burnt gases from the engine and includes one or more exhaust pipes. Depending on the overall system design, the exhaust gas may flow through one or more of:
Cylinder head and exhaust manifold
A turbocharger to increase engine power | https://huggingface.co/datasets/fmars/wiki_stem |
Akrapovič d. d. (Slovene pronunciation: [aˈkrapɔʋitʃ]) is a Slovenian manufacturer of exhaust systems that began in 1990 in the motorcycle market, and expanded into automobile exhausts in 2010 | https://huggingface.co/datasets/fmars/wiki_stem |
Exhaust heat management is the means of lessening the damaging or performance-robbing effects of internal combustion engine exhaust heat by preventing heat from escaping from the exhaust system and into the engine compartment on automobiles.
Overview
The fact that exhausts often pass near important components means that ways of protecting these components from heat soak are especially important. As a result, heat management is used as a way of reflecting, dissipating or simply absorbing the heat | https://huggingface.co/datasets/fmars/wiki_stem |
Exhaust pulse pressure charging (EPPC) is a system for supercharging two-stroke diesel engines of the loop-scavenge type. Loop-scavenge engines cannot be pressure-charged in the same way as uniflow engines or four-stroke engines because the inlet and exhaust ports are open at the same time.
Overview
The engine usually has a Roots blower to provide air for scavenging and this is arranged to deliver excess air so that air follows the exhaust gases into the exhaust manifold | https://huggingface.co/datasets/fmars/wiki_stem |
A four-stroke power valve is a device fitted to four-stroke engines that constantly adjusts the internal diameter of the exhaust system to better suit the speed of the engine. Yamaha was the first to develop such a system, called the Exhaust Ultimate Power Valve (EXUP). It first appeared on the Yamaha FZR EXUP and was later used on many other Yamahas | https://huggingface.co/datasets/fmars/wiki_stem |
A glasspack is a type of automobile muffler in which the exhaust gas passes straight through the center of the muffler. The basic design consists of one smaller tube centered inside of a larger outer tube that is enlarged or swollen in the middle. The gap between the swollen part of the larger outer tube and the smaller diameter center tube is packed full of fiberglass, hence the name | https://huggingface.co/datasets/fmars/wiki_stem |
In automotive engineering, an exhaust manifold collects the exhaust gases from multiple cylinders into one pipe. The word manifold comes from the Old English word manigfeald (from the Anglo-Saxon manig [many] and feald [fold]) and refers to the folding together of multiple inputs and outputs (in contrast, an inlet or intake manifold supplies air to the cylinders).
Exhaust manifolds are generally simple cast iron or stainless steel units which collect engine exhaust gas from multiple cylinders and deliver it to the exhaust pipe | https://huggingface.co/datasets/fmars/wiki_stem |
Rolling coal is the practice of modifying a diesel engine to emit large amounts of black or grey sooty exhaust fumes—diesel fuel that has not undergone complete combustion.
Rolling coal is sometimes used as a form of anti-environmentalism. Such modifications may include the intentional removal of the particulate filter | https://huggingface.co/datasets/fmars/wiki_stem |
Scavenging is the process of replacing the exhaust gas in a cylinder of an internal combustion engine with the fresh air/fuel mixture (or fresh air, in the case of direct-injection engines) for the next cycle. If scavenging is incomplete, the remaining exhaust gases can cause improper combustion for the next cycle, leading to reduced power output.
Scavenging is equally important for both two-stroke and four-stroke engines | https://huggingface.co/datasets/fmars/wiki_stem |
In an internal combustion engine, the geometry of the exhaust system can be optimised ("tuned") to maximise the power output of the engine. Tuned exhausts are designed so that reflected pressure waves arrive at the exhaust port at a particular time in the combustion cycle.
Two-stroke engines
Expansion chambers
In two-stroke engines where the exhaust port is opened by being uncovered by the piston (rather than by a separate valve), a tuned exhaust system usually consists of an expansion chamber | https://huggingface.co/datasets/fmars/wiki_stem |
The two-stroke power valve system is an improvement to a conventional two-stroke engine that gives a high power output over a wider RPM range.
Operation of a two-stroke engine
A stroke is the action of a piston travelling the full length of its cylinder. In a two-stroke engine, one of the two strokes combines the intake stroke and the compression stroke, while the other stroke combines the combustion stroke and the exhaust stroke | https://huggingface.co/datasets/fmars/wiki_stem |
Ignition systems are used by heat engines to initiate combustion by igniting the fuel-air mixture. In a spark ignition versions of the internal combustion engine (such as petrol engines), the ignition system creates a spark to ignite the fuel-air mixture just before each combustion stroke. Gas turbine engines and rocket engines normally use an ignition system only during start-up | https://huggingface.co/datasets/fmars/wiki_stem |
Bowl Prechamber Ignition, abbreviated BPI, is a combustion process designed for Otto cycle engines running on an air-fuel mixture leaner than stochiometric
(
λ
>
1
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{\displaystyle (\lambda >1)}
. Its distinguishing feature is a special type of spark plug, capable of reliably igniting very lean air-fuel mixtures. This spark plug is called prechamber spark plug | https://huggingface.co/datasets/fmars/wiki_stem |
Capacitor discharge ignition (CDI) or thyristor ignition is a type of automotive electronic ignition system which is widely used in outboard motors, motorcycles, lawn mowers, chainsaws, small engines, turbine-powered aircraft, and some cars. It was originally developed to overcome the long charging times associated with high inductance coils used in inductive discharge ignition (IDI) systems, making the ignition system more suitable for high engine speeds (for small engines, racing engines and rotary engines). The capacitive-discharge ignition uses capacitor discharge current to the coil to fire the spark plugs | https://huggingface.co/datasets/fmars/wiki_stem |
The Delco ignition system, also known as the Kettering ignition system, points and condenser ignition or breaker point ignition, is a type of inductive discharge ignition system invented by Charles F. Kettering. It was first sold commercially on the 1912 Cadillac and was manufactured by Delco | https://huggingface.co/datasets/fmars/wiki_stem |
A distributor is an electric and mechanical device used in the ignition system of older spark ignition engines. The distributor's main function is to route electricity from the ignition coil to each spark plug at the correct time.
Design
A distributor consists of a rotating arm ('rotor') that is attached to the top of a rotating 'distributor shaft' | https://huggingface.co/datasets/fmars/wiki_stem |
Dual Ignition is a system for spark-ignition engines, whereby critical ignition components, such as spark plugs and magnetos, are duplicated. Dual ignition is most commonly employed on aero engines, and is sometimes found on cars and motorcycles.
Dual ignition provides two advantages: redundancy in the event of in-flight failure of one ignition system; and more efficient burning of the fuel-air mixture within the combustion chamber | https://huggingface.co/datasets/fmars/wiki_stem |
High energy ignition, also known as H. E. I | https://huggingface.co/datasets/fmars/wiki_stem |
A hot-tube ignitor was an early device that fit onto the cylinder head of an internal-combustion engine, used to ignite the compressed fuel/air mixture by means of a flame heating part of the tube red-hot. A hot-tube ignitor consisted of a metal or porcelain tube, closed at one end and attached to the cylinder head at the other and an adjustable burner that could be moved to position its flame at any point along the length of the tube.
Operation
The compression stroke in the cylinder pushed some left over combustion products in the tube, followed by fresh (unburned) fuel/air mixture | https://huggingface.co/datasets/fmars/wiki_stem |
Hot-wiring is the process of bypassing a motor vehicle's ignition switch and thus starting it without the key. It is often utilized during a vehicle theft. However, a legitimate vehicle owner who has lost a vehicle key or starting a vehicle with inoperable ignition switch (e | https://huggingface.co/datasets/fmars/wiki_stem |
An ignition coil is used in the ignition system of a spark-ignition engine to transform the battery voltage to the much higher voltages required to operate the spark plug(s). The spark plugs then use this burst of high-voltage electricity to ignite the air-fuel mixture.
The ignition coil is constructed of two sets of coils wound around an iron core | https://huggingface.co/datasets/fmars/wiki_stem |
In a spark ignition internal combustion engine, ignition timing is the timing, relative to the current piston position and crankshaft angle, of the release of a spark in the combustion chamber near the end of the compression stroke.
The need for advancing (or retarding) the timing of the spark is because fuel does not completely burn the instant the spark fires. The combustion gases take a period of time to expand and the angular or rotational speed of the engine can lengthen or shorten the time frame in which the burning and expansion should occur | https://huggingface.co/datasets/fmars/wiki_stem |
Inductive discharge ignition systems were developed in the 19th century as a means to ignite the air–fuel mixture in the combustion chamber of internal combustion engines. The first versions were low tension coils, then low-tension and in turn high-tension magnetos, which were offered as a more effective alternative to the older-design hot-tube ignitors that had been utilized earlier on hot tube engines. With the advent of small stationary engines; and with the development of the automobile, engine-driven tractors, and engine-driven trucks; first the magneto and later the distributor-type systems were utilized as part of an efficient and reliable engine ignition system on commercially available motorized equipment | https://huggingface.co/datasets/fmars/wiki_stem |
Laser ignition is an alternative method for igniting mixtures of fuel and oxidiser. The phase of the mixture can be gaseous or liquid. The method is based on laser ignition devices that produce short but powerful flashes regardless of the pressure in the combustion chamber | https://huggingface.co/datasets/fmars/wiki_stem |
A low-tension coil is an electrical device used to create a spark across the points of an ignitor on early-1900s gasoline engines, generally flywheel engines, hit-and-miss engines, and other engines of that era. In modern electronic terms, a low-tension coil is simply a large inductor, an electrical device that stores energy for brief periods. The term "low tension" was the terminology of the day used to differentiate it from the term "high tension" and generally meant "low voltage" (tension) as opposed to "high voltage" (tension) | https://huggingface.co/datasets/fmars/wiki_stem |
An ignition magneto (also called a high-tension magneto) is an older type of ignition system used in spark-ignition engines (such as petrol engines). It uses a magneto and a transformer to make pulses of high voltage for the spark plugs. The older term "high-tension" means "high-voltage" | https://huggingface.co/datasets/fmars/wiki_stem |
Saab Direct Ignition is a capacitor discharge ignition developed by Saab Automobile, then known as Saab-Scania, and Mecel AB during the 1980s.
It was first shown in 1985 and put into series production in the Saab 9000 in 1988. One of the first instances of using the system was for a Formula Three racing engine (on B202 basis) developed with the help of engine builder John Nicholson, first shown in the spring of 1985 | https://huggingface.co/datasets/fmars/wiki_stem |
A spark plug is an electrical device used in an internal combustion engine to produce a spark which ignites the air-fuel mixture in the combustion chamber. As part of the engine's ignition system, the spark plug receives high-voltage electricity (generated by an ignition coil in modern engines and transmitted via a spark plug wire) which it uses to generate a spark in the small gap between the positive and negative electrodes. The timing of the spark is a key factor in the engine's behaviour, and the spark plug usually operates shortly before the combustion stroke commences | https://huggingface.co/datasets/fmars/wiki_stem |
Spark plug wires (also called high tension leads) are electrical cables used by older internal combustion engines to transmit high-voltage electricity from the distributor to the spark plugs . Tension in this instance is a synonym for voltage. High tension may also be referred to as HT | https://huggingface.co/datasets/fmars/wiki_stem |
In this type of CI engine the surface-ignition plug is mounted on an alcohol fueled direct injection diesel engine.
Basic concept
In this engine a slab of insulator material, wound with a few strands of heating wire is fixed on the combustion chamber with the wire running on the face exposed to the gases. Fuel injector is situated such that a part of the spray impinges head on this surface | https://huggingface.co/datasets/fmars/wiki_stem |
A timing mark is an indicator used for setting the timing of the ignition system of an engine, typically found on the crankshaft pulley (as pictured) or the flywheel. These have the largest radius rotating at crankshaft speed and therefore are the place where marks at one degree intervals will be farthest apart.
On older engines it is common to set the ignition timing using a timing light, which flashes in time with the ignition system (and hence engine rotation) | https://huggingface.co/datasets/fmars/wiki_stem |
VEMS is a commercial engine management system. VEMS is unlike most other EMS's in that it used to be public domain and then a form of open source.
History
The original version of VEMS was called MegaSquirtAVR and was a re-write of the popular but inadequate (at the time) MegaSquirt system | https://huggingface.co/datasets/fmars/wiki_stem |
A crank sensor (CKP) is an electronic device used in an internal combustion engine, both petrol and diesel, to monitor the position or rotational speed of the crankshaft. This information is used by engine management systems to control the fuel injection or the ignition system timing and other engine parameters. Before electronic crank sensors were available, the distributor would have to be manually adjusted to a timing mark on petrol engines | https://huggingface.co/datasets/fmars/wiki_stem |
Internal combustion engine cooling uses either air or liquid to remove the waste heat from an internal combustion engine. For small or special purpose engines, cooling using air from the atmosphere makes for a lightweight and relatively simple system. Watercraft can use water directly from the surrounding environment to cool their engines | https://huggingface.co/datasets/fmars/wiki_stem |
An exhaust gas temperature gauge (EGT gauge or EGT sensor) is a meter used to monitor the exhaust gas temperature of an internal combustion engine in conjunction with a thermocouple-type pyrometer. EGT gauges are found in certain cars and aeroplanes. By monitoring EGT, the driver or pilot can get an idea of the vehicle's air-fuel ratio (AFR) | https://huggingface.co/datasets/fmars/wiki_stem |
An idle air control actuator or idle air control valve (IAC actuator/valve) is a device commonly used in fuel-injected vehicles to control the engine's idling rotational speed (RPM). In carburetted vehicles a similar device known as an idle speed control actuator is used.
Description
The IAC actuator is an electrically controlled device, which gets its input from the vehicle's engine control unit (ECU) | https://huggingface.co/datasets/fmars/wiki_stem |
In spark ignition internal combustion engines, knocking (also knock, detonation, spark knock, pinging or pinking) occurs when combustion of some of the air/fuel mixture in the cylinder does not result from propagation of the flame front ignited by the spark plug, but when one or more pockets of air/fuel mixture explode outside the envelope of the normal combustion front. The fuel-air charge is meant to be ignited by the spark plug only, and at a precise point in the piston's stroke. Knock occurs when the peak of the combustion process no longer occurs at the optimum moment for the four-stroke cycle | https://huggingface.co/datasets/fmars/wiki_stem |
The manifold absolute pressure sensor (MAP sensor) is one of the sensors used in an internal combustion engine's electronic control system.
Engines that use a MAP sensor are typically fuel injected. The manifold absolute pressure sensor provides instantaneous manifold pressure information to the engine's electronic control unit (ECU) | https://huggingface.co/datasets/fmars/wiki_stem |
A mass (air) flow sensor (MAF) is a sensor used to determine the mass flow rate of air entering a fuel-injected internal combustion engine.
The air mass information is necessary for the engine control unit (ECU) to balance and deliver the correct fuel mass to the engine. Air changes its density with temperature and pressure | https://huggingface.co/datasets/fmars/wiki_stem |
A nitrogen oxide sensor or NOx sensor is typically a high-temperature device built to detect nitrogen oxides in combustion environments such as an automobile, truck tailpipe or smokestack.
Overview
The term NOx represents several forms of nitrogen oxides such as NO (nitric oxide), NO2 (nitrogen dioxide) and N2O (nitrous oxide, also known as laughing gas). In a gasoline engine, NO is the most common form of NOx at around 93%, while NO2 is around 5% and the rest is N2O | https://huggingface.co/datasets/fmars/wiki_stem |
An oxygen sensor (or lambda sensor, where lambda refers to air–fuel equivalence ratio, usually denoted by λ) or probe or sond, is an electronic device that measures the proportion of oxygen (O2) in the gas or liquid being analysed.
It was developed by Robert Bosch GmbH during the late 1960s under the supervision of Dr. Günter Bauman | https://huggingface.co/datasets/fmars/wiki_stem |
A throttle position sensor (TPS) is a sensor used to monitor the air intake of an engine. The sensor is usually located on the butterfly spindle/shaft, so that it can directly monitor the position of the throttle. More advanced forms of the sensor are also used | https://huggingface.co/datasets/fmars/wiki_stem |
A valvetrain or valve train is a mechanical system that controls the operation of the intake and exhaust valves in an internal combustion engine. The intake valves control the flow of air/fuel mixture (or air alone for direct-injected engines) into the combustion chamber, while the exhaust valves control the flow of spent exhaust gasses out of the combustion chamber once combustion is completed.
Layout
The valvetrain layout is largely dependent on the location of the camshaft | https://huggingface.co/datasets/fmars/wiki_stem |
A camshaft is a shaft that contains a row of pointed cams, in order to convert rotational motion to reciprocating motion. Camshafts are used in piston engines (to operate the intake and exhaust valves), mechanically controlled ignition systems and early electric motor speed controllers.
Camshafts in piston engines are usually made from steel or cast iron, and the shape of the cams greatly affects the engine's characteristics | https://huggingface.co/datasets/fmars/wiki_stem |
A hydraulic tappet, also known as a hydraulic valve lifter or hydraulic lash adjuster, is a device for maintaining zero valve clearance in an internal combustion engine. Conventional solid valve lifters require regular adjusting to maintain a small clearance between the valve and its rocker or cam follower. This space prevents the parts from binding as they expand with the engine's heat, but can also lead to noisy operation and increased wear as the parts rattle against one another until they reach operating temperature | https://huggingface.co/datasets/fmars/wiki_stem |
In the context of an internal combustion engine, a rocker arm is a valvetrain component that typically transfers the motion of a pushrod to the corresponding intake/exhaust valve.
Rocker arms in automobiles are typically made from stamped steel, or aluminum in higher-revving applications. Some rocker arms (called roller rockers) include a bearing at the contact point, to reduce wear and friction at the contact point | https://huggingface.co/datasets/fmars/wiki_stem |
A tappet is most commonly a component in an internal combustion engine which converts the rotating motion of the camshaft into linear motion of the valves, either directly or indirectly.
An earlier use of the term was for part of the valve gear in beam engines beginning in 1715. The term is also used for components in pneumatic cylinders and weaving loom | https://huggingface.co/datasets/fmars/wiki_stem |
An antifreeze is an additive which lowers the freezing point of a water-based liquid. An antifreeze mixture is used to achieve freezing-point depression for cold environments. Common antifreezes also increase the boiling point of the liquid, allowing higher coolant temperature | https://huggingface.co/datasets/fmars/wiki_stem |
A block heater is used in cold climates to warm an engine prior to starting. They are mostly used for car engines; however they have also been used in aircraft engines.
The most common design of block heater is an electrical heating element embedded in the engine block | https://huggingface.co/datasets/fmars/wiki_stem |
In turbocharged internal combustion engines, a boost controller is a device sometimes used to increase the boost pressure produced by the turbocharger. It achieves this by reducing the boost pressure seen by the wastegate.
Operation
The purpose of a boost controller is to reduce the boost pressure seen by the wastegate's reference port, in order to trick the wastegate into allowing higher boost pressures than it was designed for | https://huggingface.co/datasets/fmars/wiki_stem |
In internal combustion engines with carburetors, a choke valve or choke modifies the air pressure in the intake manifold, thereby altering the air–fuel ratio entering the engine. Choke valves are generally used in naturally aspirated engines to supply a richer fuel mixture when starting the engine. Most choke valves in engines are butterfly valves mounted upstream of the carburetor jet to produce a higher partial vacuum, which increases the fuel draw | https://huggingface.co/datasets/fmars/wiki_stem |
A cold air intake (CAI) is usually an aftermarket assembly of parts used to bring relatively cool air into a car's internal-combustion engine.
Most vehicles manufactured from the mid-1970s until the mid-1990s have thermostatic air intake systems that regulate the temperature of the air entering the engine's intake tract, providing warm air when the engine is cold and cold air when the engine is warm to maximize performance, efficiency, and fuel economy. With the advent of advanced emission controls and more advanced fuel injection methods, modern vehicles do not have a thermostatic air intake system and the factory-installed air intake draws unregulated cold air | https://huggingface.co/datasets/fmars/wiki_stem |
A serpentine belt (or drive belt) is a single, continuous belt used to drive multiple peripheral devices in an automotive engine, such as an alternator, power steering pump, water pump, air conditioning compressor, air pump, etc. The belt may also be guided by an idler pulley and/or a belt tensioner (which may be spring-loaded, hydraulic, or manual).
To allow the belt to pass over more than three pulleys with a large enough wrap angle to avoid slipping, idler pulleys which press against the back of the belt are included, forcing the belt into a serpentine shape | https://huggingface.co/datasets/fmars/wiki_stem |
Wood gas is a fuel gas that can be used for furnaces, stoves, and vehicles. During the production process, biomass or related carbon-containing materials are gasified within the oxygen-limited environment of a wood gas generator to produce a combustible mixture. In some gasifiers this process is preceded by pyrolysis, where the biomass or coal is first converted to char, releasing methane and tar rich in polycyclic aromatic hydrocarbons | https://huggingface.co/datasets/fmars/wiki_stem |
A combustion chamber is part of an internal combustion engine in which the fuel/air mix is burned. For steam engines, the term has also been used for an extension of the firebox which is used to allow a more complete combustion process.
Internal combustion engines
In an internal combustion engine, the pressure caused by the burning air/fuel mixture applies direct force to part of the engine (e | https://huggingface.co/datasets/fmars/wiki_stem |
A combustor is a component or area of a gas turbine, ramjet, or scramjet engine where combustion takes place. It is also known as a burner, burner can, combustion chamber or flame holder. In a gas turbine engine, the combustor or combustion chamber is fed high-pressure air by the compression system | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, the concept of an inverse element generalises the concepts of opposite (−x) and reciprocal (1/x) of numbers.
Given an operation denoted here ∗, and an identity element denoted e, if x ∗ y = e, one says that x is a left inverse of y, and that y is a right inverse of x. (An identity element is an element such that x * e = x and e * y = y for all x and y for which the left-hand sides are defined | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, an invariant convex cone is a closed convex cone in a Lie algebra of a connected Lie group that is invariant under inner automorphisms. The study of such cones was initiated by Ernest Vinberg and Bertram Kostant.
For a simple Lie algebra, the existence of an invariant convex cone forces the Lie algebra to have a Hermitian structure, i | https://huggingface.co/datasets/fmars/wiki_stem |
In group theory, an inverse semigroup (occasionally called an inversion semigroup) S is a semigroup in which every element x in S has a unique inverse y in S in the sense that x = xyx and y = yxy, i. e. a regular semigroup in which every element has a unique inverse | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, particularly in abstract algebra, a semigroup with involution or a *-semigroup is a semigroup equipped with an involutive anti-automorphism, which—roughly speaking—brings it closer to a group because this involution, considered as unary operator, exhibits certain fundamental properties of the operation of taking the inverse in a group: uniqueness, double application "cancelling itself out", and the same interaction law with the binary operation as in the case of the group inverse. It is thus not a surprise that any group is a semigroup with involution. However, there are significant natural examples of semigroups with involution that are not groups | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, an IP set is a set of natural numbers which contains all finite sums of some infinite set.
The finite sums of a set D of natural numbers are all those numbers that can be obtained by adding up the elements of some finite nonempty subset of D.
The set of all finite sums over D is often denoted as FS(D) | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics and computer science, the Krohn–Rhodes theory (or algebraic automata theory) is an approach to the study of finite semigroups and automata that seeks to decompose them in terms of elementary components. These components correspond to finite aperiodic semigroups and finite simple groups that are combined in a feedback-free manner (called a "wreath product" or "cascade").
Krohn and Rhodes found a general decomposition for finite automata | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, Light's associativity test is a procedure invented by F. W. Light for testing whether a binary operation defined in a finite set by a Cayley multiplication table is associative | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, a monogenic semigroup is a semigroup generated by a single element. Monogenic semigroups are also called cyclic semigroups.
Structure
The monogenic semigroup generated by the singleton set {a} is denoted by
⟨
a
⟩
{\displaystyle \langle a\rangle }
| https://huggingface.co/datasets/fmars/wiki_stem |
In abstract algebra, a branch of mathematics, a monoid is a set equipped with an associative binary operation and an identity element. For example, the nonnegative integers with addition form a monoid, the identity element being 0.
Monoids are semigroups with identity | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, Nambooripad order (also called Nambooripad's partial order) is a certain natural partial order on a regular semigroup discovered by K S S Nambooripad in late seventies. Since the same partial order was also independently discovered by Robert E Hartwig, some authors refer to it as Hartwig–Nambooripad order. "Natural" here means that the order is defined in terms of the operation on the semigroup | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, and more precisely in semigroup theory, a nilsemigroup or nilpotent semigroup is a semigroup whose every element is nilpotent.
Definitions
Formally, a semigroup S is a nilsemigroup if:
S contains 0 and
for each element a∈S, there exists a positive integer k such that ak=0.
Finite nilsemigroups
Equivalent definitions exists for finite semigroup | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, a nowhere commutative semigroup is a semigroup S such that, for all a and b in S, if ab = ba then a = b. A semigroup S is nowhere commutative if and only if any two elements of S are inverses of each other.
Characterization of nowhere commutative semigroups
Nowhere commutative semigroups can be characterized in several different ways | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, a null semigroup (also called a zero semigroup) is a semigroup with an absorbing element, called zero, in which the product of any two elements is zero. If every element of a semigroup is a left zero then the semigroup is called a left zero semigroup; a right zero semigroup is defined analogously.
According to Clifford and Preston, "In spite of their triviality, these semigroups arise naturally in a number of investigations | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, a numerical semigroup is a special kind of a semigroup. Its underlying set is the set of all nonnegative integers except a finite number and the binary operation is the operation of addition of integers. Also, the integer 0 must be an element of the semigroup | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, an ordered semigroup is a semigroup (S,•) together with a partial order ≤ that is compatible with the semigroup operation, meaning that x ≤ y implies z•x ≤ z•y and x•z ≤ y•z for all x, y, z in S.
An ordered monoid and an ordered group are, respectively, a monoid or a group that are endowed with a partial order that makes them ordered semigroups. The terms posemigroup, pogroup and pomonoid are sometimes used, where "po" is an abbreviation for "partially ordered" | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, an orthodox semigroup is a regular semigroup whose set of idempotents forms a subsemigroup. In more recent terminology, an orthodox semigroup is a regular E-semigroup. The term orthodox semigroup was coined by T | https://huggingface.co/datasets/fmars/wiki_stem |
In functional analysis a partial isometry is a linear map between Hilbert spaces such that it is an isometry on the orthogonal complement of its kernel.
The orthogonal complement of its kernel is called the initial subspace and its range is called the final subspace.
Partial isometries appear in the polar decomposition | https://huggingface.co/datasets/fmars/wiki_stem |
In algebra, a presentation of a monoid (or a presentation of a semigroup) is a description of a monoid (or a semigroup) in terms of a set Σ of generators and a set of relations on the free monoid Σ∗ (or the free semigroup Σ+) generated by Σ. The monoid is then presented as the quotient of the free monoid (or the free semigroup) by these relations. This is an analogue of a group presentation in group theory | https://huggingface.co/datasets/fmars/wiki_stem |
In algebra, the principal factor of a
J
{\displaystyle {\mathcal {J}}}
-class J of a semigroup S is equal to J if J is the kernel of S, and to
J
∪
{
0
}
{\displaystyle J\cup \{0\}}
otherwise.
Properties
A principal factor is a simple, 0-simple or null semigroup.
References
Further reading
Howie, John M | https://huggingface.co/datasets/fmars/wiki_stem |
In quantum mechanics, a quantum Markov semigroup describes the dynamics in a Markovian open quantum system. The axiomatic definition of the prototype of quantum Markov semigroups was first introduced by A. M | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematical analysis, a C0-semigroup Γ(t), t ≥ 0, is called a quasicontraction semigroup if there is a constant ω such that ||Γ(t)|| ≤ exp(ωt) for all t ≥ 0. Γ(t) is called a contraction semigroup if ||Γ(t)|| ≤ 1 for all t ≥ 0.
See also
Contraction (operator theory)
Hille–Yosida theorem
Lumer–Phillips theorem
References
Renardy, Michael; Rogers, Robert C | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, a rational monoid is a monoid, an algebraic structure, for which each element can be represented in a "normal form" that can be computed by a finite transducer: multiplication in such a monoid is "easy", in the sense that it can be described by a rational function.
Definition
Consider a monoid M. Consider a pair (A,L) where A is a finite subset of M that generates M as a monoid, and L is a language on A (that is, a subset of the set of all strings A∗) | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, in semigroup theory, a Rees factor semigroup (also called Rees quotient semigroup or just Rees factor), named after David Rees, is a certain semigroup constructed using a semigroup and an ideal of the semigroup.
Let S be a semigroup and I be an ideal of S. Using S and I one can construct a new semigroup by collapsing I into a single element while the elements of S outside of I retain their identity | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, the Rees matrix semigroups are a special class of semigroups introduced by David Rees in 1940. They are of fundamental importance in semigroup theory because they are used to classify certain classes of simple semigroups.
Definition
Let S be a semigroup, I and Λ non-empty sets and P a matrix indexed by I and Λ with entries pi,λ taken from S | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, a refinement monoid is a commutative monoid M such that for any elements a0, a1, b0, b1 of M such that a0+a1=b0+b1, there are elements c00, c01, c10, c11 of M such that a0=c00+c01, a1=c10+c11, b0=c00+c10, and b1=c01+c11.
A commutative monoid M is said to be conical if x+y=0 implies that x=y=0, for any elements x,y of M.
Basic examples
A join-semilattice with zero is a refinement monoid if and only if it is distributive | https://huggingface.co/datasets/fmars/wiki_stem |
In mathematics, a regular semigroup is a semigroup S in which every element is regular, i. e. , for each element a in S there exists an element x in S such that axa = a | https://huggingface.co/datasets/fmars/wiki_stem |
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