Search for dissertations about: "linear Navier-Stokes"

Showing result 1 - 5 of 52 swedish dissertations containing the words linear Navier-Stokes.

2. 1. Analytical vortex solutions to Navier-Stokes equation

   Author : Henrik Tryggeson; Mats Lyberg; Maarten Brons; Växjö universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; conical vortex; Navier-Stokes equation; analytical solution; 2-D vortices; turbulence; vortex ring; stretched vortex; coherent structures; Fluid mechanics; Strömningsmekanik;

   Abstract : Fluid dynamics considers the physics of liquids and gases. This is a branch of classical physics and is totally based on Newton's laws of motion. Nevertheless, the equation of fluid motion, Navier-Stokes equation, becomes very complicated to solve even for very simple configurations. READ MORE

4. 2. Numerical Simulation of Turbulent Flows for Turbine Blade Heat Transfer Applications

   Author : Jonas Larsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; k-.omega.; k-.epsilon.; explicit Runge-Kutta; finite volume; turbine; numerical method; non-linear; Navier-Stokes; supersonic; two-equation; external heat transfer; stagnation flow; two-dimensional; transition; low-Reynolds; turbulence model; impulse blade;

   Abstract : Turbine blade heat transfer is an important engineering problem characterized by complex flow fields and high turbulence levels. This thesis is focused on using a full Navier-Stokes solver with two-equation eddy-viscosity models to predict external heat-transfer in single-stage, linear, two-dimensional uncooled turbine cascades. READ MORE

5. 3. Modeling of Unsteady Flow Effects in Throughflow Calculations

   Author : Magnus Stridh; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; rotor-stator interaction; mixing-plane; linear Navier-Stokes; cascade; turbomachinery; transport equation; Linear harmonic; compressor; throughflow; turbine; Deterministic stress terms;

   Abstract : In this work an evaluation of a deterministic stress transport model and a linearized Navier-Stokes harmonic approach for including unsteady effects in the steady mixing-plane computations of a multistage transonic compressor has been performed. The results of these two models are compared with those of time-average time-accurate solutions. READ MORE

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

   Author : Magnus Stridh; Chalmers tekniska högskola; []
   Keywords : 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;

   Abstract : 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. READ MORE

7. 5. Potential Flow Panel Methods for the Calculation of Free-surface Flows with Lift

   Author : Carl-Erik Janson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; desingularized; shape optimization; Rankine source; waves; OCTOPUS; dipole; MMA; Dawson operator; boundary layer; vortex; Method of Moving Asymptotes; nonlinear; sailing yacht; four point operator; surface piercing wing; Navier-Stokes; numerical method; lift force; raised panel method; discrete Fourier transform; collocation point shift; potential flow; CFD; free surface; induced drag; SHIPFLOW; dispersion; damping; analytical method; hydrofoil;

   Abstract : Two non-linear Rankine-source panel methods are developed and implemented in the same computer code. The first method uses a four-point upwind operator on the free-surface to compute the velocity derivatives and to enforce the radiation condition while the second method uses an analytical expression for the velocity derivatives and a collocation point shift one panel upstream to prevent upstream waves. READ MORE