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Diaphragm (mechanical Device)
In mechanics, a diaphragm is a sheet of a semi-flexible material anchored at its periphery and most often round in shape. It serves either as a barrier between two chambers, moving slightly up into one chamber or down into the other depending on differences in pressure, or as a device that vibrates when certain frequencies are applied to it. A diaphragm pump uses a diaphragm to pump a fluid. A typical design is to have air on one side constantly vary in pressure, with fluid on the other side. The increase and decrease in volume caused by the action of the diaphragm alternately forces fluid out the chamber and draws more fluid in from its source. The action of the diaphragm is very similar to the action of a plunger with the exception that a diaphragm responds to changes in pressure rather than the mechanical force of the shaft. A diaphragm pressure tank is a tank which has pressurant sealed inside on one side of the diaphragm. It is favored in certain applications due to its h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanical Engineering
Mechanical engineering is the study of physical machines and mechanism (engineering), mechanisms that may involve force and movement. It is an engineering branch that combines engineering physics and engineering mathematics, mathematics principles with materials science, to design, analyze, manufacture, and maintain mechanical systems. It is one of the oldest and broadest of the List of engineering branches, engineering branches. Mechanical engineering requires an understanding of core areas including mechanics, Analytical dynamics, dynamics, thermodynamics, materials science, design, structural analysis, and electricity. In addition to these core principles, mechanical engineers use tools such as computer-aided design (CAD), computer-aided manufacturing (CAM), computer-aided engineering (CAE), and product lifecycle management to design and analyze manufacturing plants, industrial equipment and industrial machinery, machinery, HVAC, heating and cooling systems, transport systems, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scuba Diving
Scuba diving is a Diving mode, mode of underwater diving whereby divers use Scuba set, breathing equipment that is completely independent of a surface breathing gas supply, and therefore has a limited but variable endurance. The word ''scuba'' is an Acronym#Normal case and acronyms, acronym for "Self-Contained Underwater Breathing Apparatus" and was coined by Christian J. Lambertsen in a patent submitted in 1952. Scuba divers carry their own source of breathing gas, affording them greater independence and movement than surface-supplied divers, and more time underwater than freedivers. Although the use of compressed air is common, other gas blends are also used. Open-circuit scuba systems discharge the breathing gas into the environment as it is exhaled and consist of one or more diving cylinders containing breathing gas at high pressure which is supplied to the diver at ambient pressure through a diving regulator. They may include additional cylinders for range extension, de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Engine
A gas engine is an internal combustion engine that runs on a fuel gas (a gaseous fuel), such as coal gas, producer gas, biogas, landfill gas, natural gas or hydrogen. In the United Kingdom and British English-speaking countries, the term is unambiguous. In the United States, due to the widespread use of "gas" as an abbreviation for gasoline (petrol), such an engine is sometimes called by a clarifying term, such as ''gaseous-fueled engine'' or ''natural gas engine''. Generally in modern usage, the term ''gas engine'' refers to a heavy-duty industrial engine capable of running continuously at full load for periods approaching a high fraction of 8,760 hours per year, unlike a gasoline automobile engine, which is lightweight, high-revving and typically runs for no more than 4,000 hours in its entire life. Typical power ranges from to . History Lenoir There were many experiments with gas engines in the 19th century, but the first practical gas-fuelled internal combustion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compressed Natural Gas
Compressed natural gas (CNG) is a fuel gas mainly composed of methane (CH4), compressed to less than 1% of the volume it occupies at standard atmospheric pressure. It is stored and distributed in hard containers at a pressure of , usually in cylindrical or spherical shapes. CNG is used in traditional petrol/internal combustion engine vehicles that have been modified, or in vehicles specifically manufactured for CNG use: either alone (dedicated), with a segregated liquid fuel system to extend range (dual fuel), or in conjunction with another fuel ( bi-fuel). It can be used in place of petrol, diesel fuel, and liquefied petroleum gas (LPG). CNG combustion produces fewer undesirable gases than the aforementioned fuels. In comparison to other fuels, natural gas poses less of a threat in the event of a spill, because it is lighter than air and disperses quickly when released. Biomethane, biogas from anaerobic digestion or landfill, can be used. In response to high fuel prices a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autogas
Autogas is liquefied petroleum gas (LPG) used as a fuel in internal combustion engines of vehicles as well as in stationary applications such as generators. It is a mixture of propane and butane. Autogas is widely used as a "green" fuel, as its use reduces exhaust emissions by around 15% compared to petrol. One litre of petrol produces 2.3 kg of when burnt, whereas the equivalent amount of autogas (1.33 litres due to the lower density of autogas) produces only 2 kg of when burnt. CO emissions are 30% lower compared to petrol, and is reduced by 50%. It has an octane rating (MON/RON) that is between 90 and 110 and an energy content ( higher heating value—HHV) that is between 25.5 megajoules per litre (for pure propane) and 28.7 megajoules per litre (for pure butane) depending upon the actual fuel composition. Autogas is the fourth most popular automotive fuel in the world, with approximately 27.8 million of 1.47 billion passenger cars powered usi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquefied Petroleum Gas
Liquefied petroleum gas, also referred to as liquid petroleum gas (LPG or LP gas), is a fuel gas which contains a flammable mixture of hydrocarbon gases, specifically propane, Butane, ''n''-butane and isobutane. It can also contain some propylene, butylene, and isobutylene/Isobutylene, isobutene. LPG is used as a fuel gas in HVAC, heating appliances, cooking equipment, and vehicles, and is used as an aerosol propellant and a refrigerant, replacing chlorofluorocarbons in an effort to reduce the damage it causes to the ozone layer. When specifically used as a vehicle fuel, it is often referred to as autogas or just as Autogas#Terminology variations and confusion, gas. Varieties of LPG that are bought and sold include mixes that are mostly propane (), mostly butane (), and, most commonly, mixes including both propane and butane. In the northern hemisphere winter, the mixes contain more propane, while in summer, they contain more butane. In the United States, mainly two grad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuel Injection
Fuel injection is the introduction of fuel in an internal combustion engine, most commonly automotive engines, by the means of a fuel injector. This article focuses on fuel injection in reciprocating piston and Wankel rotary engines. All compression-ignition engines (e.g. diesel engines), and many spark-ignition engines (i.e. petrol (gasoline) engines, such as Otto or Wankel), use fuel injection of one kind or another. Mass-produced diesel engines for passenger cars (such as the Mercedes-Benz OM 138) became available in the late 1930s and early 1940s, being the first fuel-injected engines for passenger car use. In passenger car petrol engines, fuel injection was introduced in the early 1950s and gradually gained prevalence until it had largely replaced carburetors by the early 1990s. The primary difference between carburetion and fuel injection is that fuel injection atomizes the fuel through a small nozzle under high pressure, while carburetion relies on suction crea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuel
A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work (physics), work. The concept was originally applied solely to those materials capable of releasing chemical energy but has since also been applied to other sources of heat energy, such as Nuclear power, nuclear energy (via nuclear fission and nuclear fusion). The heat energy released by reactions of fuels can be converted into mechanical energy via a heat engine. Other times, the heat itself is valued for warmth, cooking, or industrial processes, as well as the illumination that accompanies combustion. Fuels are also used in the Cell (biology), cells of organisms in a process known as cellular respiration, where organic molecules are oxidized to release usable energy. Hydrocarbons and related organic molecules are by far the most common source of fuel used by humans, but other substances, including radioactive metals, are also utilized. Fu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Welding
Principle of burn cutting Oxy-fuel welding (commonly called oxyacetylene welding, oxy welding, or gas welding in the United States) and oxy-fuel cutting are processes that use fuel gases (or liquid fuels such as gasoline or petrol, diesel, biodiesel, kerosene, etc) and oxygen to weld or cut metals. French engineers Edmond Fouché and Charles Picard became the first to develop oxygen-acetylene welding in 1903. Pure oxygen, instead of air, is used to increase the flame temperature to allow localized melting of the workpiece material (e.g. steel) in a room environment. A common propane/air flame burns at about , a propane/oxygen flame burns at about , an oxyhydrogen flame burns at and an acetylene/oxygen flame burns at about . During the early 20th century, before the development and availability of coated arc welding electrodes in the late 1920s that were capable of making sound welds in steel, oxy-acetylene welding was the only process capable of making welds of exceptional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pressure
Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and even by industry. Further, both spellings are often used ''within'' a particular industry or country. Industries in British English-speaking countries typically use the "gauge" spelling. is the pressure relative to the ambient pressure. Various #Units, units are used to express pressure. Some of these derive from a unit of force divided by a unit of area; the International System of Units, SI unit of pressure, the Pascal (unit), pascal (Pa), for example, is one newton (unit), newton per square metre (N/m2); similarly, the Pound (force), pound-force per square inch (Pound per square inch, psi, symbol lbf/in2) is the traditional unit of pressure in the imperial units, imperial and United States customary units, US customary systems. Pressure ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pressure Regulator
A pressure regulator is a valve that controls the pressure of a fluid to a desired value, using negative feedback from the controlled pressure. Regulators are used for gases and liquids, and can be an integral device with a pressure setting, a restrictor and a sensor all in the one body, or consist of a separate pressure sensor, controller and flow valve. Two types are found: The pressure reduction regulator and the back-pressure regulator. *A pressure reducing regulator is a control valve that reduces the input pressure of a fluid to a desired value at its output. It is a normally-open valve and is installed upstream of pressure sensitive equipment. *A back-pressure regulator, back-pressure valve, pressure sustaining valve or pressure sustaining regulator is a control valve that maintains the set pressure at its inlet side by opening to allow flow when the inlet pressure exceeds the set value. It differs from an over-pressure relief valve in that the over-pressure valve is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypergolic Propellant
A hypergolic propellant is a rocket propellant combination used in a rocket engine, whose components spontaneously ignite when they come into contact with each other. The two propellant components usually consist of a fuel and an oxidizer. The main advantages of hypergolic propellants are that they can be stored as liquids at room temperature and that engines which are powered by them are easy to ignite reliably and repeatedly. Common hypergolic propellants are extremely toxic or corrosive, making them difficult to handle. In contemporary usage, the terms "hypergol" and "hypergolic propellant" usually mean the most common such propellant combination: dinitrogen tetroxide plus hydrazine. History The fact that turpentine may spontaneously combust when mixed with nitric acid was discovered as early as the late 17th century by Frederick Slare, but it remained a scientific curiosity for centuries until it was proposed to use it for rocket-assisted take off during WWII. In 1935 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
