Attached eddy

For flow past a cyhnder, the vortex street forms at Reynolds numbers above about 40. The vortices initially form in the wake, the point of formation moving closer to the cylinder as Re is increased. At a Reynolds number of 60 to 100, the vortices are formed from eddies attached to the cylinder surface. The vortices move at a velocity slightly less than V. The frequency of vortex shedding/is given in terms of the Strouhal number, which is approximately constant over a wide range of Reynolds numbers. 

The concentration of small ions in the atmosphere is determined by 1) the rate of ion-pair production by the cosmic rays and radioactive decay due to natural radioactive substances, 2) recombination with negative ions, 3) attachment to condensation nuclei, 4) precipitation scavenging, and 5) transport processes including convection, advection, eddy diffusion, sedimentation, and ion migration under the influence of electric fields. A detailed differential equation for the concentration of short-lived Rn-222 daughter ions including these terms as well as those pertaining to the rate of formation of the... 

The sensor body consists of a coil with two connections and an electrode with a tapping point. An aluminium measuring ring is attached to the object to be measured. The measurement is based on the eddy - current principle. The non-con-ductive layer between the core and the coil produces a capacitive circuit. The output signal is related to the position of the target. 

The pattern and rate of exchange of stratospheric air with the mesosphere, with the troposphere, and between hemispheres is still poorly known. Within the stratosphere a complex pattern of eddy mixing and mean motions governs the redistribution of trace constituents. In the lower stratosphere the adsorption or attachment of trace constituents to natural sulfate particles influences their subsequent transport. Some main features in stratospheric transport processes based on tracer studies are reviewed here. 

The tungsten tracer observations and the excess -1(,Pb in the tropical atmosphere are explained by the competing influence of sedimentation, slow mean motions, and eddy mixing. Radioactive aerosols in the lower stratosphere become attached to the natural sulfate particles which are of sufficient size and density to oppose upward transport to levels much above 20-25 km. (30). The coefficient of meridional eddy mixing appears to increase with latitude near the equator (29), with little seasonal change (33). At higher latitudes the rate of poleward transport exhibits large seasonal variations, with a maximum in winter (33). 

In microcarrier cultures, cell injury is due to the interactions (collisions) between microcarrier beads on which cells are attached, interactions between microcarriers and small turbulent eddies and interactions between microcarriers and bioreactor internals, such as the impeller and various probes (Papoutsakis, 1991a). To protect cells against injury in microcarrier bioreactors, an increased medium viscosity has been the only documented and studied medium alteration (Croughan et ai, 1989 Papoutsakis, 1991a Lakhotia Papoutsakis, 1992). Dextran (Sigma) has been used to increase the medium viscosity as discussed below. This is a purely physical mechanism of protection. 

Equation for C,. A number of experiments at different Prandtl numbers (mostly on tilted plates) have been carried out that permit the function C,(Q to be modeled. Observation has also revealed that there are two patterns of turbulent flow detached and attached. Attached flow, where the flow sticks to the body contour, is best exemplified by the flow on a vertical plate, and the C,(Q, = C, (90°) applying in this situation is denoted Cv,. Detached flow, where turbulent eddies rise away from the heated surface, is best exemplified by the flow on a horizontal upward-facing (heated) plate, and the C,(Q = C,(0°) applying in this situation is denoted Cf. The first step in establishing the C,(Q function has been to model how Cf and CJ depend on the Prandtl number the equations for these quantities (justified later) that have been found to best fit currently available data are... 

If the period of the eddy oscillation is resonant with the period of the tower, the tower will begin to vibrate. In one instance a tall vertical stack failed with a wind pressure of only about 10 pounds per foot. This phenomenon has only been observed in very smooth cylinders. Any roughness such as insulation, ladders and other attachments will prevent the oscillation of the dowmstream vortex. 

Mineral flotation is a three phase process where solid phase consists of mineral grains, liquid phase is mainly based on water and air as gaseos phase. In Outokumpu flotation cells air is conducted through hollow shaft to the rotating rotors direct influence. Intense eddy currents throw bubbles and pulp against the stator blades and through the gaps of the vertical blades and are distributed evenly to the flotation cell. Hydrofobic minerals attached to bubbles are lifted up to the froth area and to the concentrate duct... 

Sheet cavitation is also known as fixed, attached, cavity or pocket cavitation. Sheet cavitation is stable in a quasi-steady sense. The liquid vapor interface becomes wavy and breaks down in the closure region of the cavity. Downstream flow, which contains large scale eddies, is dominated by bubble clusters. 

Tomasek, J. J., C. J. Haaksma, R. J. Eddy, and M. B. Vaughan. 1992. Fibroblast contraction occurs on release of tension in attached collagen lattices Dependency on an organized actin cytoskeleton and serum. AnatRec 232 359-68. 

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