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Molar velocity

Component A diffuses due to the concentration gradient -dc /d. Component B diffuses due to the mean molar velocity v, v = (+ CgVg )lc, like a fish swimming upstream with the same velocity as the flowing water, /y = 0, with regard to a fixed point. [Pg.128]

For the mass balance of component A, diffusion velocity and the corresponding diffusion factor are defined with regard to the mean molar velocity V, defined by the equation... [Pg.132]

Another important leakage mechanism is a concentration-driven diffusive flux in contrast with the pressure-driven hydrodynamic flux considered previously. The flux of species A relative to the average molar velocity of all components is given by Fick s first law. [Pg.224]

Classical treatment of mass transfer is to consider a unit, of mass transfer as a measure of the interphase equilibrium changes needed to produce a desired degree of diffusion [13], This concept is best applied to the concept of a theoretical plate in distillation [4], Defining Gm as the gas superficial molar velocity (mole/hr/ft2 of tower cross section) and dy as the change of concentration of the diffusing species, then... [Pg.51]

Gl Molar velocity of fluid phase in moving bed analysis of steady-state wave, defined by equation (15), gmol/hr/cm ... [Pg.101]

The Mean Molar Velocity v of the Solvent Mixture as Reference... [Pg.104]

A is the concentration change of species 2 in the cathode compartment during a Hittorf experiment in the mean molar velocity reference system. As can be shown using Eqs. (82), (92) and (97), the following relations also hold... [Pg.140]

With the mean molar velocity v of the solvent mixture as reference velocity the reduced transference number of the non-aqueous component is equal to A, as shown in Eq. (97). [Pg.143]

The average molar velocity u can also be used as a further reference velocity. [Pg.68]

A reference system with the average molar velocity is called the particle reference system. Other reference systems and velocities are available in the literature [1.21], The diffusional flux in one system can be transferred to any other system, as is shown in the example which follows. [Pg.68]

We will now look at a system, in which the average molar velocity u according to (2.315) disappears. This gives... [Pg.224]

Vanishing average molar velocity and a system quiescent relative to the average molar velocity can be presumed, as the example indicates for the mass diffusion of ideal gases at constant pressure and temperature. [Pg.224]

We will now presuppose a quiescent system relative to the average molar velocity it, with constant temperature and pressure, and derive the diffusion equation. The molar flow of component A into the surface element dA, as in Fig. 2.57b is... [Pg.228]

The equation (2.338) for vanishing average molar velocity u = 0, can also be simplified, when it is applied to binary mixtures of ideal gases. As a good approximation, at low pressures generally up to about 10 bar, the diffusion coefficient is independent of the composition. It increases with temperature and is inversely proportional to pressure. The diffusion coefficients in isobaric, isothermal mixtures are constant. In this case (2.338) is transformed into the equation for c = const... [Pg.230]

For a barrier consisting of two sizes of straight circular holes, with Cmoi fraction occupied by small holes of radius through which pure molecular flow takes place and eyjs fraction occupied by larger holes of radius Zyis througjt which viscous flow takes place, the molar velocity for this viscous leak model would be... [Pg.823]

Real barriers contain crooked, noncircular holes distributed in size about a mean radius in the range of 0.005 to 0.03 pm. Molar velocity throu most barrier materials is found experimentally to depend on pressures as in Eq. (14.10) ... [Pg.823]

Gas mixtures. Nomenclature to be used in describing the flow of a binary gas mixture through a diffusion barrier is shown in Fig. 14.4. The problem is to determine how the molar velocities of li t and heavy components, Gi and Gj, respectively, depend on upstream and downstream... [Pg.824]

Ideal separation. When the upstream pressure is so low that only molecular flow takes place and when the downstream pressure is negligible (p jp"- Q), Eq. (14.7) shows that the molar velocity of each component is proportional to its partial pressure on the upstream faces and inversely proportional to fm ... [Pg.825]

Molar velocity, G Atom fraction light component, v... [Pg.831]

Molar velocity distribution in flow olong barrier... [Pg.831]


See other pages where Molar velocity is mentioned: [Pg.463]    [Pg.589]    [Pg.1349]    [Pg.38]    [Pg.101]    [Pg.4]    [Pg.11]    [Pg.46]    [Pg.290]    [Pg.415]    [Pg.1172]    [Pg.463]    [Pg.588]    [Pg.732]    [Pg.1557]    [Pg.1564]    [Pg.223]    [Pg.224]    [Pg.224]    [Pg.228]    [Pg.229]    [Pg.705]    [Pg.234]    [Pg.156]    [Pg.270]    [Pg.332]    [Pg.822]    [Pg.824]    [Pg.831]   


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