Orifice flames

Orifice flames Pool flames Jet flames Fireball flames Flash fire flames... 

Orifice flames can be cliaracterized as either prenii.xed or diffusion flames. In a prenii.xed flame, tlie air for combustion is already nii.xed witli the fuel gas before it leaves the orifice or pipe. In a diffusion flame, fuel e.xiting tlie orifice is piu c and the air needed for combustion diffuses into tlie fuel gas from the surroundings. Orifice flames can also be cliaracterized by tlie fame Reynolds number. Tlie flame lengtli of a diffusion flame can be calculated by Jost s equation. ... 

The flame behavior of a fire is important in determining tlie causes and effects of fires. There are several classificiitions of flames orifice flames, pool flames, fireballs. Jet fimnes, and flash fires. Orifice or pipe flames are characterized as eitlier prenii. ed flame or diffusion flmiies. Pool flames are flames on ground pools and flames on tanks. Fireballs radiate intense heat, wliich can cause fatal bums and can quickly ignite otlier materials. Jet flame or flares also radiate intense heat. 

Gaseous fuels. Gas burners can be diffusion flame burners or pre-aeraled burners. Diffusion flame burners may be relatively simple, with fuel gas burning at an orifice in the presence of... 

For a plasma temperature of 8000 K and N(,= lO Vml, A, is about 0.0006 mm, which is very much smaller than the 1-mm sampler orifice, so ions can pass through easily. Hot gases from the plasma impinge on the edges of the sampler orifice so deposits build up and then reduce its diameter with time. The surrounds of the sampler orifice suffer also from corrosive effects due to bombardment by hot species from the plasma flame. These problems necessitate replacement of the sampler from time to time. 

Confirmation of the formation of the radicals during combustion reactions has been made by inuoducing a sample of dre flames into a mass spectrometer. The sample is withdrawn from a turbulent flame which is formed into a thin column, by admitting a sample of the flame to the spectrometer drrough a piidrole orifice, usually of diameter a few tenths of a millimetre. An alternative procedure which has been successful in identifying the presence of radicals, such as CHO, has been the use of laser-induced fluorescence. 

JET FIRE Euel burning as a flame when flammable gas or vapour issues from a pipe, or other orifice, and burns on the orifice. 

Piping Restrictions - No restrictions such as check valves, flame arresters, orifice plates, etc., are permitted in the outlet piping. 

Overpressure within a vapor cloud is dependent upon outflow velocity, orifice diameter, and laminar flame speed expressed in the following semi-empirical relation ... 

If two or more systems are connected together (such as a pipe length with an orifice plate, two or more vessels connected with pipe or duct, or a compartmented vessel) and an explosion develops in No. 1 area, which generally may be at equilibrium pressure with compartments No. 2 and 3 in equilibrium with No. 2, it can cause a pressure rise in front of the flame front in the unburnt gases in the interconnecting spaces (pipe, compartment). The increased pressure in compartment or area No. 1 becomes the starting pressure for an explosion in com-... 

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