Models mass transport

Numerical dispersion or oscillation effects can occur as accidental source of error when using finite differences and finite element methods while modeling mass transport. Utilizing the criteria of numerical stability (Grid-Peclet number or Courant number) or the random walk procedure, these errors can be either reduced or even eliminated. 

Open models (mass transport) time of mass transport At > 0, scales t, x,y, z and events Models of mass transport Scales x,y,z,t and geological events Models of mass transport with mass-transfer Scales x,y,z, t, geological and physicochemical events... 

Solution-diffusion model In the solution-diffusion model, permeates dissolve in the membrane material and then diffuse through the membrane down a concentration gradient. Separation is achieved between different permeates because of differences in the amount of material that dissolves in the membrane and the rate at which the material diffuses through the membrane. The solution-diffusion model is the most widely accepted transport mechanism for many membrane processes [209,210]. Selectivity and permeability of a pervaporation membrane mainly depend on the first two steps, that is, the solubility and diffusivity of the components in the membrane. According to this model, mass transport can be divided into the three steps the mechanism is shown in Fig. 3.11 ... 

Tseronis, K., Kookos, I.K., and Theodoropoulos, C. (2008) Modelling mass transport in solid oxide fuel cell anodes a case for a multidimensional dusty gas-based model. Chem. Eng. Sci., 63, 5626-5638. 

Expression 2.1 and Expression 2.2 are our principal starting tools for modeling mass transport. We make extensive use of them in the sections and chapters that follow. To convey to the reader a flavor of how these tools are... 

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