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Positive Crankcase Ventilation
A crankcase ventilation system (CVS) removes unwanted gases from the crankcase of an internal combustion engine. The system usually consists of a tube, a one-way valve and a vacuum source (such as the inlet manifold). The unwanted gases, called "blow-by", are gases from the combustion chamber which have leaked past the piston rings. Early engines released these gases to the atmosphere simply by leaking them through the crankcase seals. The first specific crankcase ventilation system was the 'road draught tube', which used a partial vacuum to draw the gases through a tube and release them to the atmosphere. Positive crankcase ventilation (PCV) systems— first used in the Second World War and present on most modern engines— send the crankcase gases back to the combustion chamber, as part of the vehicle emissions control, in order to reduce air pollution. Two-stroke engines with a crankcase compression design do not need a crankcase ventilation system, because normal operation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Consent Decree
A consent decree is an agreement or settlement that resolves a dispute between two parties without admission of guilt (in a criminal case) or liability (in a civil case). Most often it is such a type of settlement in the United States. The plaintiff and the defendant ask the court to enter into their agreement, and the court maintains supervision over the implementation of the decree in monetary exchanges or restructured interactions between parties. It is similar to and sometimes referred to as an antitrust decree, stipulated judgment, or consent judgment. Consent decrees are frequently used by federal courts to ensure that businesses and industries adhere to regulatory laws in areas such as antitrust law, employment discrimination, and environmental regulation. Legal process The process of introducing a consent decree begins with negotiation. One of three things happens: a lawsuit is filed and the parties concerned reach an agreement prior to adjudication of the cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crankcase
A crankcase is the housing in a reciprocating engine, piston engine that surrounds the crankshaft. In most modern engines, the crankcase is integrated into the engine block. Two-stroke engines typically use a crankcase-compression design, resulting in the fuel/air mixture passing through the crankcase before entering the Cylinder (engine), cylinder(s). This design of the engine does not include an oil sump in the crankcase. Four-stroke engines typically have an oil sump at the bottom of the crankcase and the majority of the engine's oil is held within the crankcase. The fuel/air mixture does not pass through the crankcase, though a small amount of exhaust gasses often enter as "blow-by" from the combustion chamber, particularly in engines with worn rings. The crankcase often forms the upper half of the main bearing journals (with the bearing caps forming the other half), although in some engines the crankcase completely surrounds the main bearing journals. An ''open-crank'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supercharger
In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement (engine), displacement. It is a form of forced induction that is mechanically powered (usually by a belt from the engine's crankshaft), as opposed to a turbocharger, which is powered by the kinetic energy of the exhaust gases. However, up until the mid-20th century, a turbocharger was called a "turbosupercharger" and was considered a type of supercharger. The first supercharged engine was built in 1878, with usage in aircraft engines beginning in the 1910s and usage in car engines beginning in the 1920s. In piston engines used by aircraft, supercharging was often used to compensate for the lower air density at high altitudes. Supercharging is less commonly used in the 21st century, as manufacturers have shifted to turbochargers to reduce fuel consumption and increase power outputs, especially with reduced engine dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turbocharger
In an internal combustion engine, a turbocharger (also known as a turbo or a turbosupercharger) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake air, forcing more air into the engine in order to produce more power for a given displacement. Turbochargers are distinguished from superchargers in that a turbocharger is powered by the kinetic energy of the exhaust gases, whereas a is mechanically powered (usually by a belt from the engine's crankshaft). However, up until the mid-20th century, a turbocharger was called a "turbosupercharger" and was considered a type of supercharger. History Prior to the inv ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Straight Engine
The straight engine (also called inline engine) is a configuration of multi-cylinder piston engine where all of the cylinders are arranged in a single row, rather than radially or in two or more cylinder banks. Design A straight engine is easier to build than an equivalent flat engine or V engine, as it uses one cylinder head rather than two. Inline engines are also narrower than flat engines or V engines; however, they are longer and can be taller. The engine balance characteristics of a straight engine depend on the number of cylinders and the firing interval. Slant engines and horizontally-mounted engines When a straight engine is mounted at an angle from the vertical it is called a ''slant engine''. Notable slant engines include the 1959-2000 Chrysler Slant-6 engine, 1961-63 Pontiac Trophy 4 engine and the 1968-1981 Triumph Slant-4 engine. Some buses and diesel multiple unit trains take this concept further by mounting the engines horizontally (i.e. with a slant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
V Engine
A V engine, sometimes called a Vee engine, is a common configuration for internal combustion engines. It consists of two cylinder banks—usually with the same number of cylinders in each bank—connected to a common crankshaft. These cylinder banks are arranged at an angle to each other, so that the banks form a "V" shape when viewed from the front of the engine. V engines typically have a shorter length than equivalent inline engines, however the trade-off is a larger width. V6, V8 and V12 engines are the most common layout for automobile engines with 6, 8 or 12 cylinders respectively. History The first V engine, a two-cylinder V-twin, was designed by Wilhelm Maybach and used in the 1889 Daimler Stahlradwagen automobile. The first V8 engine was produced in 1903, in the form of the Antoinette engine designed by Léon Levavasseur for racing boats and airplanes. The first V12 engine was produced the following year by Putney Motor Works in London, again for use in raci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Back-fire
A backfire or afterburn is combustion or an explosion produced by a running internal combustion engine that occurs in the exhaust system, rather than inside the combustion chamber. It is also sometimes referred to as an afterfire, especially in cases where the word backfire is used to mean a fuel burn that occurs while an intake valve is open, causing the fire to move backward through the system and out through the intake instead of the exhaust. When the flame moves backward it may also be called a "pop-back". A backfire can be caused either by ignition that happens with an exhaust valve open or unburnt fuel making its way into the hot exhaust system. A visible flame may momentarily shoot out of the exhaust pipe. A backfire is often a sign that the engine is improperly tuned. The term derives from parallel experiences with early unreliable firearms or ammunition in which the explosive force was directed out at the breech instead of the muzzle. That is the origin of the us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flame Arrester
A flame arrester (also spelled arrestor), deflagration arrester, or flame trap is a device or form of construction that will allow free passage of a gas or gaseous mixture but will interrupt or prevent the passage of flame. It prevents the transmission of flame through a flammable gas/air mixture by quenching the flame on the high surface area provided by an array of small passages through which the flame must pass. The emerging gases are cooled enough to prevent ignition on the protected side. Principles Flame arresters are safety devices fitted to openings of enclosures or to pipe work, and are intended to allow flow but prevent flame transmission. A flame arrester functions by absorbing the heat from a flame front thus dropping the burning gas/air mixture below its auto-ignition temperature; consequently, the flame cannot survive. The heat is absorbed through channels (passages) designed into an element. These channels are chosen and measured as the MESG ( maximum experimen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oil Catch Tank
An oil catch tank or oil catch can is a device that is fitted into the cam/crankcase ventilation system on a car. Installing an oil catch can aims to reduce the amount of oil vapors re-circulated into the intake of the engine. Positive crankcase ventilation During normal operation of a car engine, some vapors from the cylinder pass by the piston rings and down into the crankcase. Without ventilation this can pressurize the crankcase and cause issues such as lack of piston ring sealing and damaged oil seals. To avoid this, manufacturers created a crankcase ventilation system. Originally this was often a very basic setup where a filter was placed on the top of the cam case and the pressure and vapors were vented to atmosphere. This was deemed unacceptable as it allowed fumes and oil mist to be vented out into the atmosphere which caused pollution. It could also cause issues for the occupants of the car as it could be drawn into the inside of the car, which was often unpleasant. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oil Mist
Oil mist refers to oil droplets suspended in the air in the size range 1~10 μm. Formation of oil mist Oil mist may form when high pressure fuel oil, lubricating oil, hydraulic oil, or other oil is sprayed through a narrow crack, or when leaked oil connects with a high temperature surface, vaporizes, and comes in contact with low air temperature. This happens while the fluids interact with the moving parts during machining. Smaller oil droplets than oil mist are difficult to generate under normal circumstances. Bigger oil droplets than oil mist remain in spray form; this has the advantage of a higher ignition temperature. It sinks easily, reducing fire hazard. Oil mist inside the crankcase can cause a bigger problem. Risks When the concentration of oil mist increases and reaches the lower explosion limit (LEL; 50 mg/ℓ, as defined by the IACS), explosion may occur when the mist contacts surfaces of over or a spark. The International Association of Classificatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manifold Vacuum
Manifold vacuum, or engine vacuum in a petrol engine is the difference in air pressure between the engine's intake manifold and Earth's atmosphere. Manifold vacuum is an effect of a piston's movement on the induction stroke and the airflow through a throttle in the intervening carburetor or throttle body leading to the intake manifold. It is a result of the amount of restriction of airflow through the engine. In some engines, the manifold vacuum is also used as an auxiliary power source to drive engine accessories and for the crankcase ventilation system. Manifold vacuums should not be confused with venturi vacuums, which are an effect exploited in some carburetors to establish a pressure difference roughly proportional to mass airflow and to maintain a somewhat constant air/fuel ratio. It is also used in light airplanes to provide airflow for pneumatic gyroscopic instruments. Overview The rate of airflow through an internal combustion engine is an important factor deter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
