Gas-jet

Jet separator. An interface in which carrier gas is preferentially removed by diffusion out of a gas jet flowing from a nozzle. Jet separator, jet-orifice separator, jet enricher, and jet orifice are synonymous terms. 

Blue gas, or blue-water gas, so-called because of the color of the flame upon burning (10), was discovered in 1780 when steam was passed over incandescent carbon (qv), and the blue-water gas process was developed over the period 1859—1875. Successfiil commercial appHcation of the process came about in 1875 with the introduction of the carburetted gas jet. The heating value of the gas was low, ca 10.2 MJ /m (275 Btu/fT), and on occasion oil was added to the gas to enhance the heating value. The new product was given the name carburetted water gas and the technique satisfied part of the original aim by adding luminosity to gas lights (10). 

Spouted beds are used for coarse particles that do not fluidize well. A single, high velocity gas jet is introduced under the center of a static particulate bed. This jet entrains and conveys a stream of particles up through the bed into the vessel freeboard where the jet expands, loses velocity, and allows the particles to be disentrained. The particles fall back into the bed and gradually move downward with the peripheral mass until reentrained. Particle-gas mixing is less uniform than in a fluid bed. 

FIG. 27-33 Inspirator (gas-jet) mixer feeding a large port premix nozzle of the flame retention type. High-velocity gas emerging from the spud entrains and mixes with air induced in proportion to the gas flow. The mixture velocity is reduced and pressure is recovered in the ventnii section. (F om North Ameiioan Comhnstion Handbook, 3d ed., Notih American Manufacturing Company Cleveland 1996. )... 

Figure 9-6 shows a diagram of a single-stage impulse turbine. The statie pressure deereases in the nozzle with a eorresponding inerease in the absolute veloeity. The absolute veloeity is then redueed in the rotor, but the statie pressure and the relative veloeity remain eonstant. To get the maximum energy transfer, the blades must rotate at about one-half the veloeity of the gas jet veloeity. Two or more rows of moving blades are sometimes used in eonjunetion with one nozzle to obtain wheels with low blade tip speeds and stresses. In-between the moving rows of blades are guide vanes that redireet the gas from one row of moving blades to another as shown in Figure 9-7. This type of turbine is sometimes ealled a Curtis turbine.

In the above situation, the walls cave in from the sides, cutting off the void and presenting a new surface to the incoming gas. This sequence is illustrated in Figure 32. The size of the initial bubble resulting from a detached void is typically on the order of about half the penetration depth of the gas jet. Bubbles or gas voids rise in a fluidized bed by being displaced with an inflow of solids from their perimeters. 

Plasma Plating—deposition on critical areas of metal coatings resistant to wear and abrasion normally this is done by means of a high velocity and high-temperature ionized inert gas jet. 

Step 4 Calculate the scaling parameter R, which accounts for the effect of flame shape of the relative thrusts of the wind and the gas jet discharging from the flare tip ... 

Landi,s E, and A. H. Shapiro. 1951. The Turbulent Mixing of Coaxial Gas Jets. Heat Transfer and Fluid Mechanics Institute, Preprints and Papers. Stanford University Press, California. 

On a number of occasions people have received a mild electric shock while using a carbon dioxide fire extinguisher. The gas jets from the extinguishers contain small particles of solid carbon dioxide, so a charge will collect on the horn of the extinguisher and may pass to earth via the hand of the person who is holding the horn. 

Figure 4.6. Decay of peak overpressure with distance for ignited subcritical 10-mm diameter hydrogen gas jets at various velocities, Uq. A = mean value.

A deflagration-detonation transition was first observed in 1985 in a large-scale experiment with an acetylene-air mixture (Moen et al. 1985). More recent investigations (McKay et al. 1988 and Moen et al. 1989) showing that initiation of detonation in a fuel-air mixture by a burning, turbulent, gas jet is possible, provided the jet is large enough. Early indications are that the diameter of the jet must exceed five times the critical tube diameter, that is approximately 65 times the cell size. 

U 1,1.. r,r rvlinder As soon as a glowing chip is ignited at S frll end and the moisture, which at first collects there, has disappeared,-the gas jets are turned down and finally ex-... 

A Tube Furnace.—Various forms of furnace are used. Those which are heated on the principle of the Lothar Meyer hot-air furnace by a number of pin-hole gas jets are easily regulated, and can be raised to a high temperature. The Gattermann furnace, shown in the diagram (Fig. 20), is a very convenient form. 

It consists of an oblong Lothar-Meyer air-bath about 6o cms. (24 ins.) long and 15 cms. ( bins) wide. It is heated on each side by a senes of small gas jets made by peiforating an iron pipe which runs below the air-bath. The hot air passes up the space between the outside metal casing and an inner rectangular metal bos , and then clown and into the interior of the air-bath through a number of round holes at the bottom of a central... 

W, R. Hawtlionie, D. S. Wenddell, aiid M. C. Ho((d, "Mixing and Combustion in Turbulent Gas Jets," in Third Symposium on Combustion, Williaiiis Wil- kins, Baltimore, 1949. 

Air (or Gas) Jets. The Jets are often used when there is the possibility that relatively large amounts of natural gas may enter the annulus from a producing formation as the drilling operation progresses. The air (or gas) Jets pull a vacuum on the blooey line and therefore on the annulus, thereby keeping gases in the annulus moving out of the blooey line. 

An important example of the first type is the oil smoke pot which is powered by a slow burning, gassy pyrotechnic mixt such as amm nitrate and amm chloride with a small amount of carbonaceous fuel. The resulting gas jet pulls a stream of oil from a reservoir and injects it into a venturi where the formation of the aerosol takes place... 

Transient computations of methane, ethane, and propane gas-jet diffusion flames in Ig and Oy have been performed using the numerical code developed by Katta [30,46], with a detailed reaction mechanism [47,48] (33 species and 112 elementary steps) for these fuels and a simple radiation heat-loss model [49], for the high fuel-flow condition. The results for methane and ethane can be obtained from earlier studies [44,45]. For propane. Figure 8.1.5 shows the calculated flame structure in Ig and Og. The variables on the right half include, velocity vectors (v), isotherms (T), total heat-release rate ( j), and the local equivalence ratio (( locai) while on the left half the total molar flux vectors of atomic hydrogen (M ), oxygen mole fraction oxygen consumption rate... 

Edelman, R.B., Portune, O.R, Weilerstein, G., Cochran, T.H., and Haggard, J.B., Jr., An analytical and experimental investigation of gravity effects upon laminar gas jet-diffusion flames, Proc. Combust. Inst., 14,399,1973. 

As a simplification, the term in Eq. (10) that accounts for the kinetic energy of the gas jets emerging from the gas distributor is based on the expression ( 9goVl/2, which is valid for incompressible flow. Experimental investigations show [27], that for relatively low gas velocities it is possible to represent the empirically determined loss coefficients q as accurately with this simplification as by the use of expressions for compressible flow. 

The values are clearly greater than 1, which indicates a contraction of the gas jets due to the sharp-edged holes. 

The solution to be electrosprayed is passed through the electrospray capillary (ESC) by means of a motor driven syringe. Some of the spray containing the ions then enters the pressure reducing capillary (PRC) leading to the forechamber (FCH) of the ion source. The exit tip of the PRC directs the gas jet in a direction parallel to the bottom of the FCH, i.e. across the interface plate (IN). An orifice of 4 mm diameter in the interface plate connects the FCH to the reaction chamber (RCH). The ions in the jet exiting from the PRC are deflected out of the jet towards this orifice and into the RCH by means of an electric field applied across the FCH. A weak field is also applied across the RCH. At the bottom of the RCH a small orifice, 100 pm diameter, allowed some gas and ions to leak into the vacuum of the mass... 

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