Wake effects

Huber, A. H., Incorporating building/terrain wake effects on stack effluents, pp. 353-356 in Preprints, Joint Conference on Applications of Air Pollution Meteorology. November 29-December 2, 1977, Salt Lake City, UT. American Meteorological Society, Boston, MA, 1977. 

Huber, A. H., and Snyder, W. H., Building wake effects on short stack effluents, pp. 235-242 in Preprints, Third Symposium on Atmospheric Turbulence, Diffusion and Air Quality. October 19-22, 1976, Raleigh, NC. American Meteorological Society, Boston, 1976. 

The modeling package, delivered to the EPA, includes nationwide data bases for emissions, dispersion meteorology, and population patterns. These data are used as input for a Gaussian plume model for point sources and a box model for urbanwide area sources. Prototype modeling is used for point sources that are too numerous to define individually. Building wake effects and atmospheric chemical decay are addressed. 

Guzman-Marin, R., Alam, Md. N., Szymusiak, R. et al. (2000). Discharge modulation of rat dorsal raphe neurons during sleep and waking Effects of preoptic/basal forebrain warming. Brain Res. 875, 23-34. 

Thakkar, M. M., Winston, S. McCarley, R. W. (2003b). Al receptor and adenosinergic homeostatic regulation of sleep-wakefulness effects of antisense to the Al receptor in the cholinergic basal forebrain. J. Neurosci. 23, 4278-87. 

Bixler EO, Kales A, Jacoby JA, Soldatos CR, Vela-Bueno A. Nocturnal sleep and wakefulness effects of age and sex in normal sleepers. Int J Neurosci 1984 23 3342. 

Figure 15. Vertical drop velocity from wake effects.

An alternative is a fast-switching electromagnetic two-way valve connected to a pipe T-fitting (Figure 3.81). These valves are used commercially for ink-jet printing and biomedical applications and allow a shortest injection time of less than 1 ms. The valve itself is free from wake effects and possesses a small internal volume. 

Hydrodynamic mechanisms are those which produce particle interactions through the surrounding fluid due to hydrodynamic forces and the asymmetry of the flow field around each particle. These mechanisms, which are not dependent on the relative differences in acoustic particle entrainments, can act from distances larger than the acoustic displacement and have to be considered as the main mechanism in the agglomeration of monodispersed aerosols, where particles are equally entrained. There are two main types of hydrodynamic mechanisms, namely mutual radiation pressure [50] and the acoustic wake effect [51,52]. The radiation pressure is a second-order effect which produces a force on a particle immersed in an acoustic field due to the transfer of momentum from the acoustic wave to the particle. This force moves the particles towards the pressure node or antinode planes of the applied standing wave, depending on the size and density of the particles. The mutual radial pressure can be computed from the primary wave as well as from other wave fields of nearby scatters. In fact, it gives rise to particle interactions as the result of forces produced on two adjacent particles by a non-linear combination of incident and scattered waves. 

Based on these discussions, the influence of bubble wakes has been omitted in what follows, since the wake motion is difiicult to distinguish from bulk turbulence. However, the question of wake effects has not yet been settled experimentally. 

Figure 2.10 Characteristic dispersion mechanisms in canopies from local sources close to an isolated obstacle source outside wake/canyon, showing impaction of the plume from Source (1), wake entrainment (E) and detrainment (D) from Sources 1 and 2. Note how the plume profile G(z) has a split structure in the wake with unentrained component Gp0 and detrained component Gpw. Gc denotes the typical outline of a cloud emitted upwind, showing the additional longitudinal dispersion associated with the blocking and wake effects. Here the reference cloud outline in the absence of buildings is shown as a dashed line with small circles, with streamwise dimension crj0.

Evaluation of the Wake Effects on Plume Dispersion Using Video Image Analysis... 

R.D. Adams, J. Comyn, W.C. Wake, Effect of the environment on structural adhesives, in Structural Adhesive Joints in Engineering, Chapman Hall, London, 1997, Chap. 8. 

MPam / could be attributed entirely to crack wake effects, including frictional sliding, SiC particle bridging and plastic deformation of alloy bridges, rather than to changes in the crack-tip profile. Anderson [96] measured Kic in four-point bending for both a base composite and a SiC-reinforced composite and obtained 7.8 and... 

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