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Premixed Flame
A premixed flame is a flame formed under certain conditions during the combustion of a premixed charge (also called pre-mixture) of fuel and oxidiser. Since the fuel and oxidiser—the key chemical reactants of combustion—are available throughout a homogeneous stoichiometric premixed charge, the combustion process once initiated sustains itself by way of its own heat release. The majority of the chemical transformation in such a combustion process occurs primarily in a thin interfacial region which separates the unburned and the burned gases. The premixed flame interface propagates through the mixture until the entire charge is depleted. The propagation speed of a premixed flame is known as the flame speed (or burning velocity) which depends on the convection-diffusion-reaction balance within the flame, i.e. on its inner chemical structure. The premixed flame is characterised as laminar or turbulent depending on the velocity distribution in the unburned pre-mixture (which prov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bunsen Burner Flame Types
Bunsen may refer to: * Christian Charles Josias Bunsen (1791–1860), Prussian diplomat and scholar * Frances Bunsen (1791–1876), or Baroness Bunsen, Welsh painter and author, wife of Christian * Robert Bunsen (1811–1899), German chemist, after whom is named: ** Bunsen burner ** Bunsen cell ** Bunsen crater on the Moon ** 10361 Bunsen, an asteroid ** Bunsen Reaction ** The Bunsen–Kirchhoff Award The Bunsen–Kirchhoff Award is a prize for "outstanding achievements" in the field of analytical spectroscopy. It has been awarded since 1990 by the German Working Group for Applied Spectroscopy, and is endowed with by PerkinElmer, Germany. The ..., a German award for spectroscopy * Maurice de Bunsen (1852–1932), British diplomat * Dr. Bunsen Honeydew, fictional character from the ''Muppet Show'' {{surname Low German surnames ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Universal Gas Constant
The molar gas constant (also known as the gas constant, universal gas constant, or ideal gas constant) is denoted by the symbol or . It is the molar equivalent to the Boltzmann constant, expressed in units of energy per temperature, temperature increment per amount of substance, rather than energy per temperature increment per ''particle''. The constant is also a combination of the constants from Boyle's law, Charles's law, Avogadro's law, and Gay-Lussac's law. It is a physical constant that is featured in many fundamental equations in the physical sciences, such as the ideal gas law, the Arrhenius equation, and the Nernst equation. The gas constant is the constant of proportionality that relates the energy scale in physics to the temperature scale and the scale used for amount of substance. Thus, the value of the gas constant ultimately derives from historical decisions and accidents in the setting of units of energy, temperature and amount of substance. The Boltzmann constan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spark-ignition Engine
A spark-ignition engine (SI engine) is an internal combustion engine, generally a petrol engine, where the combustion process of the air-fuel mixture is ignited by a spark from a spark plug. This is in contrast to compression-ignition engines, typically diesel engines, where the heat generated from compression ratio, compression together with the injection of fuel is enough to initiate the combustion process, without needing any external spark. Fuels Spark-ignition engines are commonly referred to as "gasoline engines" in North America, and "petrol engines" in Britain and the rest of the world. Spark-ignition engines can (and increasingly are) run on fuels other than gasoline, petrol/gasoline, such as autogas (Liquefied petroleum gas, LPG), methanol, ethanol, bioethanol, compressed natural gas (CNG), hydrogen, and (in drag racing) nitromethane. Working cycle The working cycle of both spark-ignition and compression-ignition engines may be either two-stroke cycle, two-stroke or fou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diffusion Flame
In combustion, a diffusion flame is a flame in which the oxidizer and fuel are separated before burning. Contrary to its name, a diffusion flame involves both diffusion and convection processes. The name diffusion flame was first suggested by S.P. Burke and T.E.W. Schumann in 1928, to differentiate from premixed flame where fuel and oxidizer are premixed prior to burning. The diffusion flame is also referred to as nonpremixed flame. The burning rate is however still limited by the rate of diffusion. Diffusion flames tend to burn slower and to produce more soot than premixed flames because there may not be sufficient oxidizer for the reaction to go to completion, although there are some exceptions to the rule. The soot typically produced in a diffusion flame becomes incandescent from the heat of the flame and lends the flame its readily identifiable orange-yellow color. Diffusion flames tend to have a less-localized flame front than premixed flames. The contexts for diffusion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flame Holder
A flame holder is a Components of jet engines, component of a jet engine used as an Pyrotechnic initiator, ignitor to help maintain continual combustion. In a scramjet engine the residence time of the fuel is very low and complete penetration of the fuel into the flow will not occur. To avoid these conditions flame holders are used. All continuous-combustion jet engines require a flame holder. A flame holder creates a low-speed eddy (fluid dynamics), eddy in the engine to prevent the flame from being blown out. The design of the flame holder is an issue of balance between a stable eddy and Drag (physics), drag. The simplest design, often used in amateur projects, is the can-type flame holder, which consists of a Tin can, can covered in small holes. Much more effective is the H-gutter flame holder, which is shaped like a letter H with a curve facing and opposing the flow of air. Even more effective, however, is the V-gutter flame holder, which is shaped like a V with the point in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
