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2.2. About algorithm of the computer program for modelling of thermodynamic and structural performances at phase transition of the first sort for GTSK nanoklasterov metals

Within the limits of the given operation comparative examination of fusion and crystallisation nanoklasterov, containing from N is carried out. For evolution modelling nanoklasterov at change of their temperature and diameter the settlement plan applied by us earlier (in particular, in [62, 63, 65, 66] and constructed on the basis of algorithm of the Metropolis [71]) has been used.

we Will state is short basic details of build-up of casual configurations nanochastits. In a canonical assembly casual bias of//th atom chosen in a random way, from some "old" standing About in "new" N, is spotted by a transition probability

where and #916; L and # 8725; - a difference of the total energies (2.1) corresponding to two standings About and N. Periodic boundary conditions to a modelling mesh were not applied. As us the behaviour only one nanochastitsy interested, the size of an edge of a mesh of modelling L is considerable major in relation to the size of a studied particle (Z) / £ = 10). For each chosen gang of parametres of calculation it has been executed at least IO 5 MK - macrosteps of the settlement plan (carried on each power centre) for fusion and IO 6 MK - macrosteps at crystallisation after the system transferred in an equilibrium state. Transition in an equilibrium state was spotted on stabilisation of a total energy of system (2.1). To exclude influence of an initial state on an end result for each gang of parametres a series of calculations with the subsequent averaging of effects was spent.

All effects stated in given operation, are gained with application of the computer program developed by us for computer MK - model operations nanoklasterov, the initial configuration represents: 1) "ideal" nanoklaster a crystalline lattice of the chosen type;

2) nanoklaster, containing volume and surface defects (vacancies), in a crystalline lattice of the chosen type;

3) to steam nanoklasterov, having a crystalline lattice of the chosen type, with the given initial relative positioning, including orientation of reference axes;

4) system of the difficult configuration, in particular, for modelling nanokontaktov, nanosplavov etc.

This program has been finished and improved on the basis of the program developed before P.V.Komarovym, in particular, for carrying out of examinations, featured in the thesis for a doctor's degree [170]. The task in view to develop more universal variant of algorithm and the program was us, allowing to execute the research problems put in given dissertational operation. C the account of it had been created the program having unitized structure and supposing possibility of its modernisation, allowing not only to spend modelling of the chosen system, but also to carry out a preprocessing of effects.

the algorithm Block diagramme is presented on fig. 6. Calculation is yielded in three stages. At the first stage the initial configuration of exploring system is under construction. The second stage answers immediately to evolution modelling. At the third stage processing of the gained effects is carried out.

the Initial configuration of object is under construction as follows. The user sets geometrical parametres of field of modelling, chooses type of atoms nanochastitsy, their temperatures, and also interaction potential parametres (see more in detail and. 2.3).

After program start the system equilibration is yielded under the given initial requirements and immediately process of modelling then there is a change of temperature of system to the given settlement step. Each stage of modelling is accompanied by maintenance of parametres of system: a potential part of an internal energy, co-ordinates of atoms etc., that allows to analyze further effects of modelling. Thus
the program prepares files which can be handled further with use of some auxiliary programs (see item 2.3). We will score also, that, as a rule, phase transition of the first sort is found out on a spring (fracture) on kaloricheskoj by a curve, i.e. on dependence of a potential part specific (counting on one atom) internal energy U (T) systems nanochastitsa - steam. More in detail the question on identification of phase transition of the first sort in nanoklasterah metals is stated in and. 2.4 present dissertations.

a Fig. 6. The Block diagramme of embodying of algorithm MK - model operations.

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A source: Sokolov Denis Nikolaevich. STUDYING of THERMODYNAMIC And STRUCTURAL PERFORMANCES NANOCHASTITS of METALS In FUSION And CRYSTALLIZATION PROCESSES: the THEORY And COMPUTER MODELLING. The DISSERTATION on competition of a scientific degree of the candidate of physical and mathematical sciences. Tver - 2016. 2016

More on topic 2.2. About algorithm of the computer program for modelling of thermodynamic and structural performances at phase transition of the first sort for GTSK nanoklasterov metals:

  1. 2.4.2. About algorithm of the computer program for modelling of thermodynamic and structural performances for GTSK nanoklasterov metals
  2. Chapter 3. About effects of computer experiment on modelling of thermodynamic and structural performances at phase transition of the first sort for nanoklasterov metals a Monte-Carlo method
  3. Chapter 2. About a procedure of carrying out of computer experiment on modelling of thermodynamic and structural performances nanoklasterov metals a Monte-Carlo method
  4. Sokolov Denis Nikolaevich. STUDYING of THERMODYNAMIC And STRUCTURAL PERFORMANCES NANOCHASTITS of METALS In FUSION And CRYSTALLIZATION PROCESSES: the THEORY And COMPUTER MODELLING. The DISSERTATION on competition of a scientific degree of the candidate of physical and mathematical sciences. Tver - 2016, 2016
  5. Sokolov Denis Nikolaevich. STUDYING of THERMODYNAMIC And STRUCTURAL PERFORMANCES NANOCHASTITS of METALS In FUSION And CRYSTALLIZATION PROCESSES: the THEORY And COMPUTER MODELLING. The dissertation AUTHOR'S ABSTRACT on competition of a scientific degree of the candidate of physical and mathematical sciences. Tver - 2016, 2016
  6. To a question on identification of phase transition of the first sort in nanoklasterah metals
  7. About effects of examination of structural performances in metal nanoklasterah at phase transition fusion - crystallisation
  8. About a procedure of examination of change of the shape and structural performances nanochastits at phase transition a crystal-liquid
  9. About practical aspects of modelling of phase transitions of the first sort in nanoklasterah metals
  10. 1.2. Magnetocaloric effect in materials with phase transition of the first sort.