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Iterative solutions, positive function

A closely related method is that of Boley (B8), who was concerned with aerodynamic ablation of a one-dimensional solid slab. The domain is extended to some fixed boundary, such as X(0), to which an unknown temperature is applied such that the conditions at the moving boundary are satisfied. This leads to two functional equations for the unknown boundary position and the fictitious boundary temperature, and would, therefore, appear to be more complicated for iterative solution than the Kolodner method. Boley considers two problems, the first of which is the ablation of a slab of finite thickness subjected on both faces to mixed boundary conditions (Newton s law of cooling). The one-dimensional heat equation is once again... [Pg.120]

Actually HMS is a sum of different interaction operators each related to an interaction with a different physical origin. The coupling between interactions is ensured by the iterative solution of the pseudo HF (or DFT) solution of the whole Schrodinger equation. These operators are expressed in terms of solvent response functions based on an averaged continuous solvent distribution. They will be symbolically indicated with the symbols Qx(r, r ) where r is a position vector and x stands for one of the interactions. We shall examine later the form of some of the operators, which actually are the kernels of integral equations. [Pg.6]

Continuum solvation models consider the solvent as a homogeneous, isotropic, linear dielectric medium [104], The solute is considered to occupy a cavity in this medium. The ability of a bulk dielectric medium to be polarized and hence to exert an electric field back on the solute (this field is called the reaction field) is determined by the dielectric constant. The dielectric constant depends on the frequency of the applied field, and for equilibrium solvation we use the static dielectric constant that corresponds to a slowly changing field. In order to obtain accurate results, the solute charge distribution should be optimized in the presence of the field (the reaction field) exerted back on the solute by the dielectric medium. This is usually done by a quantum mechanical molecular orbital calculation called a self-consistent reaction field (SCRF) calculation, which is iterative since the reaction field depends on the distortion of the solute wave function and vice versa. While the assumption of linear homogeneous response is adequate for the solvent molecules at distant positions, it is a poor representation for the solute-solvent interaction in the first solvation shell. In this case, the solute sees the atomic-scale charge distribution of the solvent molecules and polarizes nonlinearly and system specifically on an atomic scale (see Figure 3.9). More generally, one could say that the breakdown of the linear response approximation is connected with the fact that the liquid medium is structured [105],... [Pg.348]

Steady gas flows. From a numerical viewpoint, the iterative solution for gases does not depart significantly from that for liquids essentially, total mass, not volume, is conserved. Volume varies as a function of pressure, which varies with position detailed numerical bookkeeping to track mass balances accurately is critical to error-free results. By analogy to Equation 15-2, a similar discretization process leads to the cluster... [Pg.258]


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Functional iteration

ITER

Iter functions

Iterated

Iterated function

Iteration

Iteration iterator

Iterative

Solute function

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