Nozzle, jets

In order to maintain high energy efficiency and ensure a long service life of the materials of construction in the combustion chamber, turbine and jet nozzle, a clean burning flame must be obtained that minimizes the heat exchange by radiation and limits the formation of carbon deposits. These qualities are determined by two procedures that determine respectively the smoke point and the luminometer index. 

The inks formulated for jet printing must be very fluid, stable, and free of any particles that could cause clogging of the jet nozzles, and be capable of depositing and adhering to a substrate with a minimum of character fogging. They are generally formulated with soluble dye colorants in a suitable aqueous or solvent-based vehicle (9). 

As for oil and gas, the burner is the principal device required to successfully fire pulverized coal. The two primary types of pulverized-coal burners are circular concentric and vertical jet-nozzle array burners. Circular concentric burners are the most modem and employ swid flow to promote mixing and to improve flame stabiUty. Circular burners can be single or dual register. The latter type was designed and developed for NO reduction. Either one of these burner types can be equipped to fire any combination of the three principal fuels, ie, coal, oil and gas. However, firing pulverized coal with oil in the same burner should be restricted to short emergency periods because of possible coke formation on the pulverized-coal element (71,72). 

Some manufacturers are using relatively low-pressure air (100 kPa, or 15 Ibfiin", instead of 690 kPa, or 100 Ibf/in") and are eliminating the venturi tubes for clean-gas induction. Others have eliminated the separate jet nozzles located at the individual bags and use a single jet to inject a pulse into the outlet-gas plenum. 

Use Stellite or other hard surface material in the jet nozzle. For example 316s/s is insufficient. 

Figure 1. Blending can be improved by a shrouded blending nozzle system because the jet nozzle educts a large quantity of surrounding fluid.

Size, Spacing and Number of Burner Jets - The jet nozzles are 380 mm lengths of 25 mm stainless steel pipe. They discharge vertically from the horizontal burner lines, which run across the bottom of the stack. The jet nozzles are not insulated. 

A large variety of methods can be used for zoning, such as inclined jets, horizontal cooled jets, vertical jets, floor jets, nozzle ducts, and vortex. Examples of different methods are illustrated in Fig. 8.13. 

The assumptions that the exhaust flow has a negligible effect and that the offset jet can be treated as an equivalent wall jet were tested by Robinson and Ingham - and found to be reasonable over the majority of the surface of the tank, except close to the jet nozzle and exhaust hood. Far from the surface of the tank, the exhaust flow has a more noticeable effect. 

Having established that these assumptions are reasonable, we need to consider the relationship between the parameters of the actual offset jet and the equivalent wall jet that will produce the same (or very similar) flow far downstream of the nozzle. It can be shown that the ratio of the initial kinematic momentum per unit length of nozzle of the wall jet to the offset jet,, and the ratio of the two nozzle heights,, depend on the ratio D/B, where D is the offset distance betw een the jet nozzle and the surface of the tank, and h, is the nozzle height of the offset jet. The relationship, which because of the assumptions made in the analysis is not valid at small values of D/hj, is shown in Fig 10.72. 

A schematic diagram of the version of the Aaberg slot exhaust (ASE) system is shown in Fig. 10.81. It consists of a horizontal bench to which a vertical flange is attached, housing a rectangular exhaust slot and jet nozzle. Figure 10.82 shows the two-dimensional geometry and the coordinate system of the ASE model. 

Strahl-antrieb, m. jet propulsion, -apparat, m. jet apparatus (as steam-jet injector, pump, or blower), -asbest, m. plumose asbestos, -baryt, m. radiated barite, Bologna stone, -blende, /. a variety of sphalerite. -dUse, /. jet nozzle. 

Big-eyed bit Drill bit with one large-sized Jet nozzle, used for Jet deflection. 

Jet bit deflection A method of changing the inclination angle and direction of the wellbore by using the washing action of a jet nozzle at one side of the bit. 

Erosion Corrosion Rates at Jets, Nozzles, Orifices and Other Flow Expansions... 

Wear parts Bearings Jet-nozzle coatings Slurry valves Extrusion dies Abrasive pump seals Computer disk coatings Engine parts Medical implants Ball bearings Drawing dies Textile machinery... 

A schematic diagram of the experimental apparatus is shown in Fig. 1. A rotating fluidized bed composes of a plenum chamber and a porous cylindrical air distributor (ID400xD100mm) made of stainless sintered mesh with 20(xm openings [2-3]. The horizontal cylinder (air distributor) rotates around its axis of symmetry inside the plenum chamber. There is a stationary cylindrical filter (ID140xD100mm, 20(o.m openings) inside the air distributor to retain elutriated fine particle. A binary spray nozzle moimted on the metal filter sprays binder mist into the particle bed. A pulse air-jet nozzle is also placed inside the filter, which cleans up the filter surface in order to prevent clogging. 

The aqueous solution flows from the jet nozzle to a receiving capillary with no overflow into the outer stream, resulting in short contact times of around 0.05 s. Analysis is implemented by flowing the outer organic phase continually through a closed loop and monitoring concentration changes spectrophotometrically. The apparatus used by Freeman and Tavlarides employed capillaries with internal diameters of 2 mm, and the... 

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