Numerical model description

Mbaye M, Aidoun Z, Valkov V, Legault A. Analysis of chemical heat pumps (CHPS) Basic concepts and numerical model description. Applied Thermal Engineering... 

Nielsen, P. V. Description of supply openings in numerical models for room air distribution. ASHRAE Trans., vol. 98, pp. 963-971, 1992. 

The descriptive account of the carbon cycle presented above is a first-order model. A variety of numerical models have been used to study the dynamics and response of the carbon cycle to different transients. This subject is an extensive field because most scientists modeling the carbon cycle develop a model tailored for their particular problem. 

Since publication of the first edition, the held of reaction modeling has continued to grow and hnd increasingly broad application. In particular, the description of microbial activity, surface chemistry, and redox chemistry within reaction models has become broader and more rigorous. Reaction models are commonly coupled to numerical models of mass and heat transport, producing a classification now known as reactive transport modeling. These areas are covered in detail in this new edihon. 

In the years since the discovery of nickel and iron in the catalytic centres, numerous different descriptions of the catalytic cycle of hydrogenase have been proposed. These were based on different oxidation states of the metal centres, and different sequences of transfer of electrons and hydrous. Although the reaction cycle has not been definitively resolved, the spectroscopic evidence places constraints on possible models that should be considered. 

An adequate quantitative description of such a situation requires a two- or even three-dimensional approach. Today, a great variety of numerical models are available that allow us to solve such models almost routinely. However, from a didactic point of view numerical models are less suitable as illustrative examples than equations that can still be solved analytically. Therefore, an alternative approach is chosen. In order to keep the flow field quasi-one-dimensional, the single well is replaced by a dense array of wells located along the river at a fixed distance xw (Fig. 25.2c). Ultimately, the set of wells can be looked at as a line sink. This is certainly not the usual method to exploit aquifers Nonetheless, from a qualitative point of view a single well has properties very similar to the line sink. 

Although the asymptotic critical regime with the Ising-like scaling exponents has been neglected in this description, the fit curves in Fig. 8 are a reasonable parameterization for all three coefficients in the one-phase regime. This parameterization then serves as input for the numerical model. A more detailed discussion of the whole procedure can be found in [100],... 

According to the principles mentioned above, the derivation of a numerical model of ocean ecosystem A requires either a detailed description of its states or derivation of an adequate complex of numerical models of energy exchange between the trophic levels taking place in A, as well as the interactions of biotic, abiotic, and hydrophysical factors. Of course, in this case an availability of a certain set of hypotheses is assumed concerning the character of the balanced relationship in ecosystem A. 

Solvent permittivity — is an index of the ability of a solvent to attenuate the transmission of an electrostatic force. This quantity is also called the -> dielectric constant. -> permittivity decreases with field frequency. Static (related to infinite frequency) and optical op (related to optical frequencies) permittivities are used in numerous models evaluating the solvation of ions in polar solvents under both static and dynamic conditions. Usually the refractive index n is used instead of op (n2 = eop), as these quantities are available for the majority of solvents. The theory of permittivity was first proposed by Debye [i]. Systematic description of further development can be found in the monograph of Frohlich [ii]. Various aspects of application to reactions in polar media and solution properties, as well as tabulated values can be found in Fawcetts textbook [iii]. 

These mathematical representations are complex and it is necessary to use numerical techniques for the solution of the initial-boundary value problems associated with the descriptions of fluidized bed gasification. The numerical model is based on finite difference techniques. A detailed description of this model is presented in (11-14). With this model there is a degree of flexibility in the representation of geometric surfaces and hence the code can be used to model rather arbitrary reactor geometries appropriate to the systems of interest. [The model includes both two-dimensional planar and... 

Chenevez J, Baklanov A, Sorensen JH (2004) Pollutant transport schemes integrated in a numerical weather prediction model Model description and verification results. Meteorol Appkll (3) 265-275... 

For modelling the drying process in wood, different approaches have been proposed in the past. In numerical models the description of the mass loss of water by a heterogeneous reaction, as introduced by [9], is advantageous with respect to numerical stability. However, the macrokinetic data used in this approach is specific to certain boundary conditions, which excludes this model from a general use. Thus, a different approach is chosen here. 

The difference between model and calculation undoubtedly comes from the effect of the free interface, which was not taken into account here. This model also lacks the interactions between bubbles in reality, the rising bubbles collide with each other and then lose kinetic energy. The numerous collisions between quasi-rigid bubbles probably explain the widening of the plume seen in fig. 11. Moreover, the numerical model did not take into account the interactions that might exist between the bubbles in the plume and those at the sparger outlet. Nor did the model take into account bubble diameter distribution. This poor description of a plume is not related to EA. 

We distinguish clay smear from fault gouge in accordance with Smith (1980). We identify clay smear based on the description of Lehner and Pilaar (1997), our own observations of the Rhine graben browncoal mines and the results of our numerical modelling. In accordance with Smith (1980), clay smears are understood to be clay fault filling derived from bedded material. 

Shape change algorithms vary from simple analytical descriptions to a variety of numerical models of increasing sophistication. For example, numerical front tracking or string models [12, 62] and surface triangularization (3D-simulations [303])... 

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