Drag force transversal

Flow FFF is the most versatile FFF subtechnique (and one of the most versatile of all separation techniques) because it requires nothing more than the interaction of the transverse stream with a suspended or dissolved component. This interaction is made up of the drag forces which induce... 

In a cross-flow classifier, the feed material enters the flow medium at one point in the classification chamber, at an angle to the direction of fluid flow with a component of velocity transverse to the flow and is fanned out under the action of field, inertia and drag forces. Particles of different sizes describe different trajectories and so can be separated according to size. 

The terms on the right-hand side of Eq. (11.4) correspond to interphase drag force, virtual mass force. Basset force and lift force, respectively, /l is a transversal lift... 

In another attempt to account for turbulence effects Jakobsen [65] performed turbulence modelling of the drag force, and showed that this procedure gave rise to a transversal force acting in the opposite direction compared to the classical lift force [7, 8, 152]. 

The interphase forces considered were steady drag, added (virtual) mass and lift. The steady drag force on a collection of dispersed bubbles with a given average diameter was described by (5.48) and (5.34). The transversal lift force was determined by the conventional model (5.65), whereas the added mass force was approximated by (5.112). 

By applying turbulence modeling to the drag force, negative transversal forces arise. The resulting transversal force was written as [12] ... 

It follows from (2.6.14) and (2.6.15) that to calculate the drag force of a body of revolution of any shape with arbitrary orientation in a Stokes flow, it suffices to know the value of this force only for two special positions of the body in space. The axial (Fy) and transversal (Fl) drags can be obtained both theoretically... 

The axial and transverse motion of two drops close to each other was considered in [525], Some leading terms were obtained in the asymptotic expansion of the drag force with respect to the small dimensionless distance between the drop boundaries. The case of interaction between a solid particle and a drop was also investigated. 

A cell suspended in a spiral microchannel experiences a transverse Dean drag force due to the two major Dean vortices and the inertial hft forces due to the rectangular cross section. The Dean force experienced by the cells or particles while traveling through a spiral channel can be derived assuming Stokes drag [2, 3] ... 

The magnitude of the transverse periodic force is assumed identical to the drag force on a cylinder in steady flow. For a velocity less than 8 ft s , the maximum drag force is F) ax = 1-43 lb ft . The actual transverse force (lift) is expected to be less than this value. Experimental values (Reference 3)... 

The flow past the body, as shown in Fig. 24.2(b) for a cylinder in steady flow, produces an asymmetric (fore-aft) pressme distribution around the cylinder, which traverses the flow axis at a given (Strouhal) frequency at a low or intermediate Re. This pressure distribution, in turn, generates an oscillating lift (or transverse) force with near-zero mean, in addition to an inline mean drag force, and an oscillating inline force of smaller magnitude over the steady force. 

For a swirling motion consider only the radial and transverse components of the velocity of a particle. Determine the velocities of a particle in such a field having only the drag force acting in resistance to the movement of the particle. 

Apart from the flow-induced drag force, moving particles experience an additional transverse lift force due to the non-uniform relative velocity between shear-layers and particles [29]. The resulting non-uniform pressure distribution around the resolved particle surface leads to a lift force which acts towards the direction of higher slip velocity. Figure 6 illustrates this behaviour by means of the horizontal offset between the initial and final positions of the upper particles shown in Fig. 6a-f. 

Transverse drag force (F,) or (TDH) aeting on hair is given by ... 

Table 4.1. Transverse and longitudinal drag forces acting on hairs (1.0 denier, 10 pm calculated diameter) of various lengths at the divergent section for the nozzle of 45 , 2.2 mm at 0.5 bar (gauge) [Source Reference 1]...

Transverse drag force parameters on hair Longitudinal drag force parameters on hair ... 

Various planes in the nozzle Velocity of air on hair in transverse direction (m/s) Reynolds number (A) Drag eoeffieient (pDt) Drag force (mN) Velocity of air on hair in longitudi nal direction (m/s) Reynolds number (Re) Drag coefficient (Cut) " Drag force (mN)... 

Transverse drag forces aeting on hair constituted by fibers of different deniers is shown in Figure 4.8. The ealculated diameters of 1.0, 1.2, and 1.4 denier fibers are 10, 11, and 12 pm. The transverse drag force acting on 1.4 denier hairs is higher in comparison to that on 1.2 and 1.4 denier hairs. Most of the bending of hairs is likely to take place at planes in between 0 to... 

A CFD model is employed for simulation to get airflow pattern, resultant direetions of airflow, velocities of resultant airflow and its components in air nozzles. The transverse and longitudinal drag forces acting on hairs are computed. 

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