Vortex, vapor

In a submerged-tube FC evaporator, all heat is imparted as sensible heat, resulting in a temperature rise of the circulating hquor that reduces the overall temperature difference available for heat transfer. Temperature rise, tube proportions, tube velocity, and head requirements on the circulating pump all influence the selec tion of circulation rate. Head requirements are frequently difficult to estimate since they consist not only of the usual friction, entrance and contraction, and elevation losses when the return to the flash chamber is above the liquid level but also of increased friction losses due to flashing in the return line and vortex losses in the flash chamber. Circulation is sometimes limited by vapor in the pump suction hne. This may be drawn in as a result of inadequate vapor-liquid separation or may come from vortices near the pump suction connection to the body or may be formed in the line itself by short circuiting from heater outlet to pump inlet of liquor that has not flashed completely to equilibrium at the pressure in the vapor head. 

The term refrigeration refers to the gas coming into contact with evaporator coils on a dx vapor-compression cycle, coils on an absorption cycle, vortex... 

Deflagrative combustion of an extended, flat vapor cloud is very ineffective in producing damaging blast waves because combustion products have a high rate of side relief accompanied by vortex formation. 

Chart, 204, 205, 207 Vortex, 190 Water hammer, 98 Wire mesh separators, 246, 247 Calculations, 247-254 Efficiency, 248, 250 Installation, 251-253 k-value for mesh, table, 249 Mesh patterns, 247 Pressure drop, 249, 251 Specifications form, 254 Vapor velocity, 247, 250 Wire mesh types, 248... 

Total protection from liquids and vapors can be provided by an impervious hood incorporating a glass or plastic window. Unfortunately, these are very hot and may require additional ventilation directly from an air line, or perhaps through a device known as a vortex tube that converts supplied compressed air to either a cool or warm flow as required. 

Add 200 pi water to the cell pellet and sonicate briefly at low power. Use 50 pi homogenate for a protein determination and 100 pi for lipid extraction. To 100 pi homogenate add 4 ml chloroform/methanol 2/1 (v/v). Leave for 1 h at room temperature and add 0.8 ml of 0.73% NaCl. Vortex and centrifuge for 5 min at 1000xg to separate the phases. Remove the lower chloroform phase and add 10 nmol cho-lesteryl oleate and 10 nmol triolein as a cold carrier. Dry the sample under nitrogen. Take the sample up in 25 pi chloroform/methanol 2/1 (v/v) and spot the sample on a silica gel plate (0.5 cm streak). Rinse the tube with 25 pi chloroform/methanol 2/1 (v/v) and spot the sample on a silica gel plate. Develop the plate with hexane/diethyl-ether/acetic acid, 70/30/1 (v/v/v). Remove the plate from the tank when the solvent front almost reaches the top, dry the plate, and expose briefly to iodine vapor to localize the cholesteryl oleate. Scrape the spots into scintillation vials, mix thoroughly, and count in a scintillation counter. 

The details of the transitions and the vortex behavior depend on the actual channel dimensions and wall-temperature distributions. In general, however, for an application like a horizontal-channel chemical-vapor-deposition reactor, the system is designed to avoid these complex flows. Thus the ideal boundary-layer analysis discussed here is applicable. Nevertheless, one must exercise caution to be sure that the underlying assumptions of one s model are valid. 

Within the framework of the AsiaFlux program, Saigusa et al. (2005) measured the C02 fluxes since 1993 in the forest ecosystem of Takayama using an aerodynamic method to estimate the vertical gradient of C02 concentration and a vortex divergence method to calculate the coefficient of diffusion over the forest canopy. Also, measurements were made of vortex fluxes of sensible heat, water vapor, and C02. 

Bottom liquid outlets. Sufficient residence time must be provided in the bottom of the column to separate any entrained gas from the leaving liquid. Gas in the bottom outlet may also result from vortexing or from forthing caused by liquid dropping from the bottom tray (a waterfall pool effect). Vortex breakers are commonly used, and liquid-drop height is often restricted. Inadequate gas separation may lead to bottom pump cavitation or vapor choking the outlet line. 

Redistribution of vapor depends on a balance between the vertical and horizontal pressure gradients (157). The horizontal pressure gradient depends on column diameter, and diminishes rapidly as column diameter increases. This explains the strong effect of diameter in item 4 above. Another important factor cited by Porter and Ali (157) is vortex formation. This can cause downward flows of vapor in the bed. Downward flows were actually measured by Kabakov and Rozen (154) and Porter and Ali (157). 

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