Nozzle central

TsNUProrazdanii. 1984. Recommendations on Heating and Ventilating Systems Design with Directing Nozzles. Central Research Institute for Industrial Buildings, Moscow. 

Moisan, M., Barbeau, Moreau, S., J., Pelletier, Tabrizian, M., Yahia, L.H. (2001), Int. J. Pharm., vol. 226, p. 1. Molchanov Yu.S., Starik, A.N. (1984), Kinetics of Vibrational Energy Exchange in Hydrocarbon Combustion Products during Gas Expansion in Supersonic Nozzles, Central Institute of Aviation Motors, Preprint 10160,... 

Radial gas phase flow from the center outward in the wash zone formed by two discs. To mix intensively wash liquid is sprayed centrally by means of a nozzle central into the gas flow. The throat opening in the center of the wash zone may be adjusted to the gas flow by means of the check ring. To improve droplet separation swirling flow is induced by baffles mounted on the disc rim (Fig. 3-22). 

Shamlou and Zolfagharian (1990) have studied liquid-jet stirred suspension and found the mechanism of suspension to be similar to impeller-stirred suspension. The preferred design consists of a downward-pointing feeder nozzle centrally mounted with the tip fully submerged in the slurry. They found that to achieve an acceptable cloud height, the tip of the nozzle should be below half the slurry height. They showed also that ... 

Opposed Jet Mills. These mills are, in some ways, similar to the fluidized-bed machine however, in this case two opposed nozzles accelerate particles, causing them to collide at a central point (Fig. 16). A turbine classifier is again used to separate the product that has achieved the desired fineness from that which must be internally recycled for further grinding. 

Figure 11-69 describes a typical central system. Either water or direct-expansion refrigerant coils or air washers may be used for cooling. Steam or hot-water coils are available for heating. Humidification may be provided by target-type water nozzles, pan humidifiers, air washers, or sprayed coils. Air cleaning is usually provided by cleanable or throwaway filters. Central-station air-conditioning units in capacities up to about 50,000 cu ft/min are available in prefabricated units. 

Fine water spray systems may be potentially superior to CO9 apphcations and may replace halon environments such as telephone central offices and computer rooms. In the fine spray dehveiy system, water is delivered at relatively high pressure (above 100 psi [0.689 MPa]) or by air atomization to generate droplets significantly smaUer than those generated by sprinklers. Water flow from a fine spray nozzle potentially extinguishes the fire faster than a sprinkler because the droplets are smaUer and vaporize more quickly. Preliminaiy information indicates that the smaller the droplet size, the lower the water flow requirements and the less chance of water damage. 

These filters are similar in configuration to a Nutsche filter, but instead of one filter plate there is a series of plates inside the vessel. The filtrate is pulled through the filter media in the center of each plate to a central pipe that discharges out the bottom of the devise. The bottom plate of the filter usually discharges its filtrate thought a separate nozzle. These filters are usually used with slurries where a smaller quantity of solids is to be collected. 

There are various designs of flare tips that incorporate such features as central steam injection, an annular ring of steam nozzles, internal air-inspirating steam nozzles, windshields, etc. Table 2 provides some details of suitable types from which selection may be made. 

This discussion will address needs, applications, performance characteristics, and design considerations for LVHV exhaust ventilation. The applications are primarily for dust control. LVHV systems can be effective for protecting workers from dust exposures and for recovering valuable process materials. The equipment, excepting the nozzles, involves technology that is the same as for large central vacuum cleaning systems. 

A 2 IB. Braun airlift fermenter with a working volume of about 2000 ml was used. Sterile air is sparged through a sintered plate located near the bottom of the central concentric tube. There was no mechanical stirring only the air nozzle was forced through the centred tube and the flow directed to the annulus tube side. Aeration causes circulation of media the flow is gentle without serious shear forces. The temperature is maintained at 26 °C. 

This system produces a steady laminar flow with a flat velocity profile at the burner exit for mean flow velocities up to 5m/s. Velocity fluctuations at the burner outlet are reduced to low levels as v /v< 0.01 on the central axis for free jet injection conditions. The burner is fed with a mixture of methane and air. Experiments-described in what follows are carried out at fixed equivalence ratios. Flow perturbations are produced by the loudspeaker driven by an amplifier, which is fed by a sinusoidal signal s)mthesizer. Velocity perturbations measured by laser doppler velocimetry (LDV) on the burner symmetry axis above the nozzle exit plane are also purely sinusoidal and their spectral... 

A polymer of the polyacrylamide type was injected as a 0.5% solution from an axially-placed nozzle at the bellmouth entrance. The experiments showed that the central thread provided drag reduction almost equivalent to premixed solutions of the same total polymer concentration flowing in the pipe. Overall concentrations of 1, 2, 4, and 20 ppm were used. Moreover, the effects were additive 2 ppm thread overall concentration plus 2 ppm premixed gave drag reductions equivalent to 4 ppm of either type. Reynolds numbers of up to 300,000 were investigated. In other experiments, a number of different polymer fluids were injected on the centerline of a water pipe-flow facility [857]. Two distinct flow regions were identified ... 

Figure 12-4 Schematic of disk-bowl centrifuge 1, Ring 2, bowl 3,4, collectors for products 5, feed tank 6, tube 7,8, discharge nozzles 9,10, funnels for collectors 11, through channels 12, bowl 13, bottom 14, thick-walled tube 15 hole for guide 16, disk fixator 17, disks 18 central tube (From Azbel and Cheremisinoff, 1983.)...

Fixed systems are complete installations piped from a central foam station to tanks or equipment, discharging through fixed delivery outlets. These outlets take the form of foam chambers, monitor nozzles, foam-water spray nozzles, etc. Any required pumps are permanently installed. 

The geometry of the ramjet system simulated is shown in Fig. 7.1, which consists of a cylindrical inlet connected to a central dump combustor that has an exhaust nozzle. This specific geometry was chosen because extensive studies have been made in the past of the interaction between acoustics, vorticity dynamics, and chemical energy release in this system [17-20]. These earlier gas-phase flow studies are very helpful in interpreting the current multiphase flow simulations. 

The observed flame features indicated that changing the atomization gas (normal or preheated air) to steam has a dramatic effect on the entire spray characteristics, including the near-nozzle exit region. Results were obtained for the droplet Sauter mean diameter (D32), number density, and velocity as a function of the radial position (from the burner centerline) with steam as the atomization fluid, under burning conditions, and are shown in Figs. 16.3 and 16.4, respectively, at axial positions of z = 10 mm, 20, 30, 40, 50, and 60 mm downstream of the nozzle exit. Results are also included for preheated and normal air at z = 10 and 50 mm to determine the effect of enthalpy associated with the preheated air on fuel atomization in near and far regions of the nozzle exit. Smaller droplet sizes were obtained with steam than with both air cases, near to the nozzle exit at all radial positions see Fig. 16.3. Droplet mean size with steam at z = 10 mm on the central axis of the spray was found to be about 58 /xm as compared to 81 pm with preheated air and 96 pm with normal unheated air. Near the spray boundary the mean droplet sizes were 42, 53, and 73 pm for steam, preheated air, and normal air, respectively. The enthalpy associated with preheated air, therefore, provides smaller droplet sizes as compared to the normal (unheated) air case near the nozzle exit. Smallest droplet mean size (with steam) is attributed to decreased viscosity of the fuel and increased viscosity of the gas. 

The droplet number density presented in Fig. 16.4 indicates the solid-cone nature of the spray except in the immediate vicinity downstream of the nozzle exit. On the spray centerline at 2 = 10 mm, steam provides a lower number density as compared to the two air cases. This is due to the expansion of the spray jet at a relatively lower Reynolds number with steam and rapid vaporization of smaller sized droplets. At increased radial positions and 2 = 10 mm, a peak in the number density corresponds to the spray cone boundary. This peak shifts radially outwards with an increase in axial distance due to the expansion of the spray cone. Similar phenomena are observed for the normal and preheated air cases except that droplet number density for the preheated air case is much higher on the spray central axis (at r = 0). This is attributed to the effect of preheated air on atomization (i.e., larger mean droplet size and smaller number density with normal air as compared to that for heated atomization... 

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