Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Set Method

The evolution of cj) in a flow field is given by the so-called weak-form equation  [Pg.7]

For gas-liquid bubble flow, F and F+ are the gas and liquid velocities, respectively, and the zero-level set of 4 marks the bubble interface, which moves with time. For gas-droplets flows, on the other hand, F and V+ represent the [Pg.7]

To compute the motion of two immiscible and incompressible fluids such as a gas liquid bubble column and gas-droplets flow, the fluid-velocity distributions outside and inside the interface can be obtained by solving the incompressible Navier-Stokes equation using level-set methods as given by Sussman et al. (1994)  [Pg.8]

The surface-tension force Fa in Eq. (7) is smoothed and distributed into the thickness of the interface. In order to circumvent numerical instability, the fluid properties such as density and viscosity in the interface region are determined with a continuous transition  [Pg.8]

Since the values for p((p), p( p), and the surface-tension force could be distorted if the variation of V p along the interface is very large, the thickness of the interface needs to be maintained uniformly, i.e. V = 1 (Sussman et al., 1998). In the algorithm developed, the general level set function 4 (x,t) is replaced by a [Pg.8]


The first quantum mechanical improvement to MNDO was made by Thiel and Voityuk [19] when they introduced the formalism for adding d-orbitals to the basis set in MNDO/d. This formalism has since been used to add d-orbitals to PM3 to give PM3-tm and to PM3 and AMI to give PM3(d) and AMl(d), respectively (aU three are available commercially but have not been published at the time of writing). Voityuk and Rosch have published parameters for molybdenum for AMl(d) [20] and AMI has been extended to use d-orbitals for Si, P, S and Q. in AMI [21]. Although PM3, for instance, was parameterized with special emphasis on hypervalent compounds but with only an s,p-basis set, methods such as MNDO/d or AMI, that use d-orbitals for the elements Si-Cl are generally more reliable. [Pg.383]

Two-dimensional semiclassical studies described in section 4 and applied to some concrete problems in section 6 show that, when no additional assumptions (such as moving along a certain predetermined path) are made, and when the fluctuations around the extremal path are taken into account, the two-dimensional instanton theory is as accurate as the one-dimensional one, and for the tunneling problem in most cases its answer is very close to the exact numerical solution. Once the main difficulty of going from one dimension to two is circumvented, there seems to be no serious difficulty in extending the algorithm to more dimensions that becomes necessary when the usual basis-set methods fail because of the exponentially increasing number of basis functions with the dimension. [Pg.133]

Based on the flame-hole dynamics [59], dynamic evolutions of flame holes were simulated to yield the statistical chance to determine the reacting or quenched flame surface under the randomly fluctuating 2D strain-rate field. The flame-hole d5mamics have also been applied to turbulent flame stabilization by considering the realistic turbulence effects by introducing fluctuating 2D strain-rate field [22] and adopting the level-set method [60]. [Pg.63]

J. Kim, S. H. Chung, K. Y. Ahn, and J. S. Kim, Simulation of a diffusion flame in turbulent mixing layer by the flame hole dynamics model with level-set method. Combust. Theory Model. 10(2) 219-240, 2006. [Pg.66]

Simulations of multiphase flow are, in general, very poor, with a few exceptions. Basically, there are three different kinds of multiphase models Euler-Lagrange, Euler-Euler, and volume of fluid (VOF) or level-set methods. The Euler-Lagrange and Euler-Euler models require that the particles (solid or fluid) are smaller than the computational grid and a finer resolution below that limit will not give a... [Pg.339]

In this work, we developed the safeguard active-set method by modifying the active-set method for thermodynamic equilibrium in order to include the classical nucleation theory. At tn, assume that the partition ( (r ), M(t ), N(t ) and the crystallization time tciyst(t ) forM(t ) are known. For a new feed vector and RH at Vu compute W(tn+i), M(t i), N(t + )) and tciyst(t +i) as follows ... [Pg.682]

This paper is intended to describe recent progress on the development of the level-set method and IBM in the context of the advanced front-capturing and front-tracking methods. The paper is also intended to discuss the application of them for the 3-D DNS of two complex three-phase flow systems as described earlier. [Pg.3]

Ge and Fan (2005) developed a 3-D numerical model based on the level-set method and finite-volume technique to simulate the saturated droplet impact on a superheated flat surface. A 2-D vapor-flow model was coupled with the heat-transfer model to account for the vapor-flow dynamics caused by the Leidenfrost evaporation. The droplet is assumed to be spherical before the collision and the liquid is assumed to be incompressible. [Pg.29]

The flow field of the impacting droplet and its surrounding gas is simulated using a finite-volume solution of the governing equations in a 3-D Cartesian coordinate system. The level-set method is employed to simulate the movement and deformation of the free surface of the droplet during impact. The details of the hydrodynamic model and the numerical scheme are described in Sections... [Pg.39]

Immersed-Boundary I Level-Set Method for Particle-Flow Interaction... [Pg.51]

In system 1, the 3-D dynamic bubbling phenomena in a gas liquid bubble column and a gas liquid solid fluidized bed are simulated using the level-set method coupled with an SGS model for liquid turbulence. The computational scheme in this study captures the complex topological changes related to the bubble deformation, coalescence, and breakup in bubbling flows. In system 2, the hydrodynamics and heat-transfer phenomena of liquid droplets impacting upon a hot flat surface and particle are analyzed based on 3-D level-set method and IBM with consideration of the film-boiling behavior. The heat transfers in... [Pg.58]

An example is the get/set method pattern used in JavaBeans for component properties. [Pg.446]

This does not mean that there is no creativity in implementation. Rather, it means that any level of refinement involves a set of constraining design decisions that define a limited and consistent toolbox of techniques for downstream work. To continue our lower-level example, use your creativity to address the problems that matter rather than come up with your own convention for dealing with get and set methods. [Pg.507]

Therefore, you should avoid accessing variables outside your own class always go through access methods instead and try to provide higher-level services instead of only get and set methods. [Pg.658]

The main feature of the CBS (complete basis set) methods (e.g. CBS-Q [15] and CBS-QB3 [20]) is extrapolation to the complete basis set limit at the UMP2 level. Additional calculations [UMP4 and UQ-CISD(T) or UCCSD(T)] are performed to estimate higher-order effects. A scaled ZPVE, together with a size-consistent empirical correction and a spin-contamination correction, are added to yield the total CBS energy of the molecule. [Pg.164]

Various models for BBB permeability prediction are summarized in terms of their data sets, methods employed, statistical parameters and descriptors, important outcomes in Tables 22.1 and 22.2, respectively. [Pg.544]

Table 22.1 Data sets, methods and statistical parameters of the models... [Pg.545]

The test set method of validation is rather straightforward, but requires some caution. First, the test set samples must be sufficiently representative of samples that the model will be applied to in the future. Otherwise, external validation can provide misleading results - in either an optimistic or pessimistic manner. Under-representing the anticipated sample states could lead to optimistic results, while the use of sample states not represented in the calibration data could lead to pessimistic results. A practical disadvantage of the test set method is that it requires that the reference analytical method be performed on an additional set of samples beyond the original calibration samples, which can be an issue if the cost of each reference analysis is high. [Pg.410]

Berg D, Malinowsky K, Reischauer B et al (2011) Use of formalin-fixed and paraffin-embedded tissues for diagnosis and therapy in routine clinical settings. Methods Mol Biol 785 109-122... [Pg.214]

Valeev, E.F., Janssen, C.L. Second-order Moller-Plesset theory with linear R12 terms (MP2-R12) revisited auxiliary basis set method and massively parallel implementation. J. Chem. Phys. 2004, 121, 1214-27. [Pg.147]

Set method of designing Training and Test Sets. The sixth Training Set (named Random) was constructed by randomly selecting molecules for the Training Set with the remainder becoming the Test Set. Statistical analysis of the predicted bioactivities was performed in Microsoft Excel 97 unless so noted. [Pg.193]

One conceptually simple remedy for the shortcomings of DFT regarding dispersion forces is to simply add a dispersion-like contribution to the total energy between each pair of atoms in a material. This idea has been developed within localized basis set methods as the so-called DFT-D method. In DFT-D calculations, the total energy of a collection of atoms as calculated with DFT, dft> is augmented as follows ... [Pg.226]


See other pages where Set Method is mentioned: [Pg.39]    [Pg.499]    [Pg.175]    [Pg.154]    [Pg.298]    [Pg.343]    [Pg.329]    [Pg.96]    [Pg.235]    [Pg.63]    [Pg.2]    [Pg.5]    [Pg.6]    [Pg.6]    [Pg.6]    [Pg.12]    [Pg.13]    [Pg.29]    [Pg.30]    [Pg.50]    [Pg.58]    [Pg.227]    [Pg.109]    [Pg.175]   


SEARCH



Active set methods

Basis Set Methods

Bloch Sum Basis Set - The LCAO Method

Complete basis set method

Cut set method

Experimental data sets, multivariate methods

Fields and sets of chains analytical method

Hartree-Fock method basis sets used

Hartree-Fock method from Gaussian basis sets

Hydro-setting method

Instrumental data sets, multivariate methods

Level-set method

Methods and basis sets

Minimization Active Set Methods

Net Flow and Rough Sets Two Methods for Ranking the Pareto Domain

Obstacle-set method

Quantum chemical methods basis sets

Quantum chemistry methods basis sets

Rough set method

Statistical methods correlation between many data sets

Steam-setting method

© 2024 chempedia.info