Component fluid-phase mass density

If the particles are composed of multiple chemical species, then usually the fluid phase will be also. In such cases, it is necessary to introduce a vector of internal coordinates whose components are the mass of each chemical species seen by a particle. Obviously, the sum of these internal coordinates is equal to the fluid mass seen by a particle. By definition, if is the mass of component a, then integration over phase space leads to a component fluid-phase mass density ... 

It should be noted that the introduction of fluid/solid interaction has no effect on the macroscopic equations since F2jt exists only at the fluid/solid interface. The relaxation time, tk, is estimated based on the viscosity and mass density representations given by Eqs. (20) and (21) of the Mi component and is detailed in Ref. [37, 43, 44], This model has been shown to satisfy Galilean invariance.44 Furthermore, in this interparticle potential model, the separation of a two-phase fluid into its components is automatic.37... 

Systems for pumping slurries around a process plant are similar to systems for pumping liquids, in regard to the calculation of performance on a basis of head. The slurry can be regarded as a fluid having a density computed from the ratio of solids to liquid (usually water) and the respective densities of the two phases. If the slurry composition is stated on a mass basis, the slurry density is calculated by calculating the volumes of each component of mass, and dividing the sum of the masses by the sum of the volumes. 

If we include the porosity n, the discussions of Sect. 3.6 can be directly used. Assume that within the REV of volume AV all variables are homogeneous. If the mass of the ath component of the fluid phase is denoted as na, the volume fraction (occasionally referred to as the volume molar concentration) coa and the component mass density Pa are defined by... 

Homogeneous reactions occur in the fluid phase, and the volume available for reaction is sV. Solid-catalyzed reactions occur on the catalyst surface, and area available for the reaction is Vpca where V is the total reactor volume (i.e., gas plus catalyst), is the average density of catalyst in the reactor (i.e., mass of catalyst per total reactor volume), and is the surface area per mass of catalyst. The pseudohomogeneous reaction rate calculated using Equation (10.37) is multiplied by eF to get the rate of formation of component A in moles per time. The equivalent heterogeneous rate is based on the catalyst surface area and is multiplied by Vpc flc to obtain the rate of formation of component A in moles per time. Setting the two rates equal gives... 

Phase behaviour describes the phase or phases in which a mass of fluid exists at given conditions of pressure, volume (the inverse of the density) and temperature (PVT). The simplest way to start to understand this relationship is by considering a single component, say water, and looking at just two of the variables, say pressure and temperature. 

In model equations, Uf denotes the linear velocity in the positive direction of z, z is the distance in flow direction with total length zr, C is concentration of fuel, s represents the void volume per unit volume of canister, and t is time. In addition to that, A, is the overall mass transfer coefficient, a, denotes the interfacial area for mass transfer ifom the fluid to the solid phase, ah denotes the interfacial area for heat transfer, p is density of each phase, Cp is heat capacity for a unit mass, hs is heat transfer coefficient, T is temperature, P is pressure, and AHi represents heat of adsorption. The subscript d refers bulk phase, s is solid phase of adsorbent, i is the component index. The superscript represents the equilibrium concentration. 

SFC is complementary to the other classic techniques of GC or normal phase HPLC. The migration of the solute results from a distribution mechanism between the apolar stationary phase and a slightly polar eluting mobile phase. The solvation capacity of the mobile phase is governed by both temperature and pressure of the supercritical fluid. Therefore as the density of the supercritical fluid mobile phase is increased, components retained in the column can be made to elute. The resistance to mass transfer between the stationary and the mobile phases is less than in HPLC because diffusion is about ten times greater than in liquids. The C factor in Van Deemter s equation being smaller, the velocity of the mobile phase can therefore be increased without an appreciable loss of efficiency (Figure 6.5). Moreover, as the viscosity of the mobile phase is close to that of a gas, GC... 

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