Sökning: "Reynolds Averaged Navier-Stokes"

Visar resultat 1 - 5 av 62 avhandlingar innehållade orden Reynolds Averaged Navier-Stokes.

  1. 1. Fluid Flow and Heat Transfer Simulations for Complex Industrial Applications : From Reynolds Averaged Navier-Stokes towards Smoothed Particle Hydrodynamics

    Författare :Md Lokman Hosain; Rebei Bel Fdhila; Konstantinos Kyprianidis; Erik Dahlquist; Hailong Li; Moncho Gomez Gesteira; Mälardalens högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Computational Fluid Dynamics; Heat transfer; Industrial applications; Reynolds Averaged Navier-Stokes; Smoothed Particle Hydrodynamics; Energy enginnering; Thermal Management; Process control; Energy- and Environmental Engineering; energi- och miljöteknik;

    Sammanfattning : Optimal process control can significantly enhance energy efficiency of heating and cooling processes in many industries. Process control systems typically rely on measurements and so called grey or black box models that are based mainly on empirical correlations, in which the transient characteristics and their influence on the control parameters are often ignored. LÄS MER

  3. 2. Large Eddy Simulations of Complex Flows in IC-Engine's Exhaust Manifold and Turbine

    Författare :Johan Fjällman; Laszlo Fuchs; Mihai Mihaescu; Ricardo Martinez-Botas; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Large Eddy Simulations; Reynolds Averaged Navier-Stokes; Turbocharger; Turbine; Curved Pipes; Pulsatile Flow; Proper Orthogonal Decomposition; Large Eddy Simulations; Reynolds Averaged Navier-Stokes; Turboladdare; Turbin; Rörkrök; Pulserande Flöde; Proper Orthogonal Decomposition; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : The thesis deals with the flow in pipe bends and radial turbines geometries that are commonly found in an Internal Combustion Engine (ICE). The development phase of internal combustion engines relies more and more on simulations as an important complement to experiments. LÄS MER

  4. 3. Modeling Unsteady flow Effects in 3D Throughflow Calculations

    Författare :Magnus Stridh; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; throughflow; turbomachinery; mixing-plane; rotor-stator interaction; cascade; Deterministic stress terms; Linear harmonic; compressor; preconditioned GMRES; Unsteady; linear Navier-Stokes; turbine;

    Sammanfattning : The flow field in a transonic multistage compressor is compressible, three-dimensional and highly unsteady and can be predicted in principle by the exact time-accurate Navier-Stokes equations. The high Reynolds number encountered in multistage turbomachinery together with the wall-bounded nature of the flow environment however prevent the use of DNS to solve the exact N-S equations. LÄS MER

  5. 4. Numerical Simulation of High Reynolds Number Wall Bounded Flow

    Författare :Tobias Persson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; subgrid model; DES; high; validation; LES; numerical simulation; near-wall;

    Sammanfattning : In this thesis, four different numerical methods are used for predictions of high Reynoldsnumber (Re), wall bounded flows; Large Eddy Simulation (LES) with two different subgrid(turbulence) models, the One Equation Eddy Viscosity model (OEEVM) and the MixedModel (MM), Monotone Integrated LES (MILES), Detached Eddy Simulation (DES) andReynolds Averaged Navier Stokes (RANS). The LES calculations are combined with a wallmodel based on the law-of-the-wall and in DES a hybrid RANS/LES method is used forhandling the near wall region. LÄS MER

  7. 5. Homogenization of some problems in hydrodynamic lubrication involving rough boundaries

    Författare :John Fabricius; Guy Bayada; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mathematics; partial differential equations; calculus of variations; homogenization theory; tribology; hydrodynamic lubrication; thin film flows; Reynolds equation; surface roughness; Weyl decomposition; Matematik; Mathematics; Matematik;

    Sammanfattning : This thesis is devoted to the study of some homogenization problems with applications in lubrication theory. It consists of an introduction, five research papers (I–V) and a complementary appendix.Homogenization is a mathematical theory for studying differential equations with rapidly oscillating coefficients. LÄS MER