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The paper presents a mathematical model of distribution the discharged heat water from thermal power plant under various operational capacities on the aquatic environment. It was solved by the Navier-Stokes and temperature equations for an incompressible fluid in a stratified medium were based on the splitting method by physical parameters which approximated by the finite volume method. The numerical solution of the equation system was divided into four stages. At the first step it was assumed that the momentum transfer carried out only by convection and diffusion. While the intermediate velocity field was solved by 5-step Runge-Kutta method. At the second stage, the pressure field was solved by found the intermediate velocity field. Whereas Poisson equation for the pressure field was solved by Jacobi method. The third step assumes that the transfer was carried out only by pressure gradient. Finally the fourth step of the temperature equation was also solved as motion equations, with 5-step Runge-Kutta method. The algorithm was parallelized on high-performance computer. The obtained numerical results of three-dimensional stratified turbulent flow were compared with experimental data. What revealed qualitatively and quantitatively approximately the basic laws of hydrothermal processes occurring in the reservoir-cooler.

This paper presents the mathematical model of the thermal power plant in reservoir under different hydrometeorological conditions, which is solved by three dimensional Navier - Stokes and temperature equations for an incompressible fluid in a stratified medium. A numerical method based on the projection method, which divides the problem into four stages. At the first stage it is assumed that the transfer of momentum occurs only by convection and diffusion. Intermediate velocity field is solved by fractional steps method. At the second stage, three-dimensional Poisson equation is solved by the Fourier method in combination with tridiagonal matrix method (Thomas algorithm). At the third stage it is expected that the transfer is only due to the pressure gradient. Finally stage equation for temperature solved like momentum equation with fractional step method. To increase the order of approximation compact scheme was used. Then qualitatively and quantitatively approximate the basic laws of the hydrothermal processes depending on different hydrometeorological conditions are determined.

This paper presents a method for a synthetic turbulence generation (STG) to be used in a segregated hybrid Reynolds-averaged Navier-Stokes (RANS)-Large-Eddy Simulation (LES) approach. The present method separates the LES inflow plane into three sections where a local velocity signal is decomposed from the turbulent flow properties of the upstream RANS solution. Depending on the wall-normal position in the boundary layer, the local flow Reynolds and Mach number specific time, length and velocity scales with different vorticity contents are imposed on the LES inflow plane. The STG method is assessed by comparing the resulting skin-friction, velocity and Reynolds-stress distributions of zonal RANS-LES simulations of flat plate boundary layers with available pure LES, DNS, and experimental data. It is shown that for the presented flow cases a satisfying agreement within a short RANS-to-LES transition of two boundary-layer thicknesses is obtained. The method is further used for the simulation of a shock-boundary-layer interaction around an airfoil at transonic flow conditions, where the separated flow region are analyzed by an embedded LES and the remaining flow is determined by a RANS solution.

This paper presents the mathematical model of the thermal power plant in cooling pond under different meteorological conditions, which is solved by three dimensional Navier-Stokes equations and temperature equation for an incompressible fluid in a stratified medium. A numerical method based on the projection method, which divides the problem into three stages. At the first stage it is assumed that the transfer of momentum occurs only by convection and diffusion. Intermediate velocity field is solved by method of fractional steps. At the second stage, three-dimensional Poisson equation is solved by the Fourier method in combination with tridiagonal matrix method (Thomas algorithm). At the third stage it is expected that the transfer is only due to the pressure gradient. The compact scheme was used to increase the order of approximation. Then the basic laws of the hydrothermal processes depending on different hydrometeorological conditions were determined qualitatively and quantitatively approximate.

In this paper presents the mathematical model of hydrothermal processes in thermal power plant with different wind direction scenarios in the water reservoir, which is solved by the Navier - Stokes and temperature equations for an incompressible fluid in a stratified medium. Numerical algorithm based on the method of splitting by physical parameters. Three dimensional Poisson equation is solved with Fourier method by combination of tridiagonal matrix method (Thomas algorithm)., {"references":["Fletcher C.A. Computational Techniques for Fluid Dynamics. Vol 2:\nSpecial Techniques for Differential Flow Categories, Berlin: Springer-\nVerlag. 1988. p. 493.","Roache P.J. Computational Fluid Dynamics, Albuquerque, NM:\nHermosa Publications. 1972. p. 446.","Tolstykh, A.I. Compact difference scheme and their applications to fluid\ndynamics problems. M.: Nauka. 1990. p. 230.","Peyret, R., Taylor, D. Th. Computational Methods for Fluid Flow. New\nYork: Berlin: Springer-Verlag. 1983. p. 358.","Yanenko, N.N. The Method of Fractional Steps. New York: Springer-\nVerlag. In J.B.Bunch and D.J. Rose (eds.), Space Matrix Computations,\nNew York: Academics Press. 1979. p. 168.","Lesieur M., Metais O., Comte P. Large eddy simulation of turbulence.\nNew York, Cambridge University Press, 2005. p. 219.","Tannehill J.C., Anderson D.A., and Pletcher R.H. Computational Fluid\nMechanics and Heat Transfer. 2nd ed., New York: McGraw-Hill. 1997.\np. 816.","Tennekes H., Lumley J.L. A first course in turbulence. The MIT Press.\n1972. p. 390.","Issakhov A. Large eddy simulation of turbulent mixing by using 3D\ndecomposition method Issue 4, J. Phys.: Conf. Ser. 318 042051. 2011.\n[10] Zhumagulov B., Issakhov A. Parallel implementation of numerical\nmethods for solving turbulent flows. Vestnik NEA RK. - 2012, - Ôäû\n1(43) - pp.12-24.\n[11] Issakhov A. Parallel algorithm for numerical solution of threedimensional\nPoisson equation. Proceedings of world academy of\nscience, engineering and technology, Issue 64 (2012), pp. 692-694"]}

This paper presents the mathematical model of the thermal power plant influence in the aquatic environment, which is solved by the Navier - Stokes and temperature equations for an incompressible fluid in a stratified medium. Numerical algorithm based on the method of splitting by physical parameters with combination of Fourier method for Poisson equation.

A synthetic turbulence generation (STG) method for flows at low and high Reynolds and Mach numbers to provide LES inflow boundary conditions of zonal Reynolds-averaged Navier-Stokes (RANS)- large-eddy simulation (LES) method simulations is presented. The present method separates the LES inflow plane into three sections where a local velocity signal is decomposed from the turbulent flow properties of the upstream RANS solution. Depending on the wall-normal position in the boundary layer the local flow Reynolds and Mach number specific time, length, and velocity scales with different vorticity content are imposed on the LES inflow plane. The STG method is assessed by comparing the resulting skin-friction, velocity, and Reynolds-stress distributions of zonal RANS-LES simulations of subsonic and supersonic flat plate flows with available pure LES, DNS, and experimental data. It is shown that for the presented flow cases a satisfactory agreement within a short RANS-to-LES transition of two boundary-layer thicknesses is obtained.

Parallel implementation of algorithm of numerical solution of Navier-Stokes equations for large eddy simulation (LES) of turbulence is presented in this research. The dynamic Smagorinsky model is applied for sub-grid simulation of turbulence. The numerical algorithm was worked out using a scheme of splitting on physical parameters. At the first stage it is supposed that carrying over of movement amount takes place only due to convection and diffusion. Intermediate field of velocity is determined by method of fractional steps by using Thomas algorithm (tridiagonal matrix algorithm). At the second stage the determined intermediate field of velocity is used for determination of the field of pressure. Three dimensional Poisson equation for the field of pressure is solved using over relaxation method.