Particles cylinder

For an ensemble of uncorrelated ID particles (cylinders, layers) with a Gaussian96 particle thickness distribution the ID scattering intensity is [197]... 

Figure 6.9.13 Measured and calculated radial coke profiles in a partly regenerated Pt-Al203 particle (cylinders dp = 1.6 mm, Lp = 2-8 mm 2p = 0.5, and Tp = 3.5). From Kern and Jess (2005).

Irregular-shaped sand and bauxite particle Cylinder (normal flow)... 

The only drag measurements on nonspherical particles (cylinders, bars) in viscoelastic fluids are due to Rodrigue et al. (1984). They measured free-settling velocities in a polyisobutylene in kerosene/polybutene solution (Boger fluid), with a fluid relaxation time of 7.2 msec. They found it necessary to modify Eq. (16) by incorporating the following correction factor due to viscoelasticity ... 

Bowen, P., Humphy-Baker, R., Herard, C, Particle Size Distribution Measurement of Regular Anisotropic Particles - Cylinders and Platelets, in Proc. World Congress Part. Technol. 3, Brighton, 1998, Paper No.29. 

The simplest type of centrifugal device is the cyclone separator (Fig. 3.4), which consists of a vertical cylinder with a conical bottom. The centrifugal force is generated by the fluid motion. The mixture enters in a tangential inlet near the top, and the rotating motion so created develops centrifugal force which throws the particles radially toward the wall. 

Figure A3.1.2. A collision cylinder for particles with velocity v striking a small region of area A on the surface of a contamer within a small time interval 5f Here is a unit nomial to the surface at the small region, and pomts into the gas.

Notice that each collision is counted twice, once for the particle with velocity v and once for the particle with velocity v We also note that we have assumed that the distribution fiinctions/do not vary over distances which are the lengths of the collision cylinders, as the interval 6t approaches some small value, but still large compared with the duration of a binary collision. 

Figure A3.1.3. The collision cylinder for collisions between particles with velocities v and v. The origin is placed at the centre of the particle with velocity v and the z-axis is in the direction of v - v. The spheres indicate tire range, a, of the intennolecular forces.

The number of (v, v)-collision cylinders in the region 8r8v is equal to the number of particles with velocity v in this region,/(r,v,0 r5v. 

Stosszahlansatz. The total number of (Vj, v)-collisions taking place in bt equals the total volume of the (Vj, v)-collision cylinders times the number of particles with velocity per unit volume. 

The gas has to be dilute because the collision cylinders are assumed not to overlap, and also because collisions between more than two particles are neglected. Also it is assumed that/hardly changes over 8r so that the distribution fimctions for both colliding particles can be taken at the same position r. 

Thus die increase of particles in our region due to restituting collisions with an impact parameter between b and b + Ab and azimuthal angle between e and e + de (see figure A3.1.7 can be obtained by adjusting the expression for the decrease of particles due to a small collision cylinder ... 

Flard spherocylinders (cylinders witli hemispherical end caps) were studied using computer simulations [118]. In addition to a nematic phase, such particles also display a smectic-A phase, in which tire particles are arranged in liquid-like layers. To observe tliis transition, ratlier monodisperse particles are needed. The smectic-A phase was indeed observed in suspensions of TMV particles [17]. 

Both (i) and (ii) necessitate recourse to a model of pore shape. By far the commonest, chosen on grounds of simplicity, is the cylinder but the slit model is being increasingly used where the primary particles are plate-like, and the model where the pore is the cavity between touching spheres is beginning to receive attention. 

The discrepancy between the pore area or the core area on the one hand and the BET area on the other is proportionately larger with silica than with alumina, particularly at the higher degrees of compaction. The fact that silica is a softer material than alumina, and the marked reduction In the BET area of the compact as compared with that of the loose material, indicates a considerable distortion of the particles, with consequent departure of the pore shape from the ideal of interstices between spheres. The factor R for cylinders (p. 171), used in the conversion to pore area in the absence of a better alternative, is therefore at best a crude approximation. 

One advantage of sintering is the close control of si2e and shape of the abrasive particle. Extmded, cylindricaHy shaped, sintered abrasives of circular cross section were produced from bauxite (24) and from calcined alumina (25). The Uelt2 sintered bauxite was also later produced in extmded cylinder form and designated as 76A. Extmded sintered abrasives of a wide variety of cross-sectional configurations, eg, square and triangular, were later patented (26). 

Eig. 5. Target efficiency of spheres, cylinders, and ribbons. The curves apply for conditions where Stokes law holds for the motion of the particle (see also N j ia Table 5). Langmuir and Blodgett have presented similar relationships for cases where Stokes law is not vaUd (149,150). Intercepts for ribbon or... 

Mixing. The most widely used mixing method is wet ball milling, which is a slow process, but it can be left unattended for the whole procedure. A ball mill is a barrel that rotates on its axis and is partially filled with a grinding medium (usually of ceramic material) in the form of spheres, cylinders, or rods. It mixes the raw oxides, eliminates aggregates, and can reduce the particle size. 

The capillary retention forces in the pores of the filter cake are affected by the size and size range of the particles forming the cake, and by the way the particles have been deposited when the cake was formed. There is no fundamental relation to allow the prediction of cake permeabiUty but, for the sake of the order-of-magnitude estimates, the pore size in the cake may be taken loosely as though it were a cylinder which would just pass between three touching, monosized spheres. If dis the diameter of the spherical particles, the cylinder radius would be 0.0825 d. The capillary pressure of 100 kPa (1 bar) corresponds to d of 17.6 pm, given that the surface tension of water at 20°C is 12.1 b mN /m (= dyn/cm). 

Here iC is the intrinsic anisotropy constant due to the crystalline anisotropy. After the demagnetization in the longest direction, k is the shape-dependent constant (for an infinite cylinder k = 1.38), M is the exchange constant, and R the particle radius. An infinite cylinder with only shape anisotropy gives... 

An important appHcation of MMCs in the automotive area is in diesel piston crowns (53). This appHcation involves incorporation of short fibers of alumina or alumina—siHca in the crown of the piston. The conventional diesel engine piston has an Al—Si casting alloy with a crown made of a nickel cast iron. The replacement of the nickel cast iron by aluminum matrix composite results in a lighter, more abrasion resistant, and cheaper product. Another appHcation in the automotive sector involves the use of carbon fiber and alumina particles in an aluminum matrix for use as cylinder liners in the Prelude model of Honda Motor Co. 

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