Turbulence effects

Wind-induced pressures. The pressure at a location on the envelope depends on the shape of the building, the shielding of the building, the wind direction, and the wind speed. Air-exchange due to wind turbulence effects is normally not considered. 

As previously outlined, perfect mixing is assumed in the individual zones. The spatial distribution of air velocities, contaminant concentrations, and air temperatures in a zone cannot be determined. Air exchange due to wind turbulence effects is not considered. 

The neglect of a low turbulence effect and a laminar flow is not justified in regions close to solid surfaces where the turbulent velocity fluctuations... 

Zhibin, Z. and Guoquan, Z. Investigations of the Collection Efficiency of an Electrostatic Precipitator with Turbulent Effects. Aerosol Science and Technology. 20 (1994) 2, pp. 169-176. 

Inlet channel width to each pump is considered optimum at 2 to prevent secondary turbulence effects. [3]... 

Tamanini, F., Turbulence Effects on Dust Explosion Venting, Ibid, p. 52. 

Based on the flame-hole dynamics [59], dynamic evolutions of flame holes were simulated to yield the statistical chance to determine the reacting or quenched flame surface under the randomly fluctuating 2D strain-rate field. The flame-hole d5mamics have also been applied to turbulent flame stabilization by considering the realistic turbulence effects by introducing fluctuating 2D strain-rate field [22] and adopting the level-set method [60]. 

In addition to bulk liquid turbulence effects, suspended particles maybe involved in collisions with one another or with solid surfaces within the vessel. This phenomenon has been extensively studied in micro-carrier cultures [60] and appears to be significant at high concentrations [61]. Rosenberg [69] and Meijer [72] applied the approach of Cherry and Papoutsakis [60] to the study of collision phenomena involving spherical plant cell aggregates of 190 and 100 pm, respectively. In both cases it was concluded that for typical biomass concentrations, particle-particle interactions were of less significance than particle-impeller collisions. 

Further extensions of Madej ski s mod ell4011 may include (a) turbulence effect, (b) Rayleigh instability or Taylor instability and droplet breakup, (c) vibrational energy, and (d) influence of solidification on flow)514 Some issues related to the deformation and solidification of droplets on a flat substrate in splat quenching have been addressed in Refs. 380 and 514. To date, analytical models addressing droplet impingement on a semi-solid surface have not been found in available literature. 

Specific research subjects have emerged with respect to improved descriptions of specific phenomena. Some time ago, it was speculated that gas-solid interactions and turbulence effects on reaction kinetics would be important areas of advance in the modeling art. Gas-solid interactions include both chemical formation of aerosols and reactions on surfaces of pre-existing suspended particulate matter. Because of differing effects of a material in the gas phase and in some condensed phase, it will be important to characterize transformation processes. The achex (Aerosol Characterization hYperiment) program recently carried out under the direction of Hidy will provide an extensive data base with which to test new ways of treating the gas-solid interaction problem. 

Ibrahim, S. S., R. W. Bilger, and N. R. Mudford, Turbulence Effects on Chemical Reactions in Smog Chamber Flows, Atmos. Environ., 21, 2609-2621 (1987). 

Where high levels of marine vessel motion are experienced and high product quality 1s required the secondary turbulence effects of the baffling, required to control resonant waves and primary turbulence, will not allow the product specifications to be met. These conditions require more advanced vessel Internals to be utilized that eliminate the secondary turbulence while still controlling resonant waves and primary turbulence. 

Both approaches were actually using the characteristics of the laminar flow in micro structures, which enable a defined deposition of catalysts as the characteristics of the laminar flow remain unchanged. The deposition is not affected by unforeseeable turbulent effects. The reactors were used for catalyst preparation and for catalyst testing simultaneously. 

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