Sökning: "stokes equations"
Visar resultat 1 - 5 av 159 avhandlingar innehållade orden stokes equations.
1. Initial-Boundary-Value Problems for the Stokes and Navier–Stokes Equations on Staggered Grids
Sammanfattning : In the first part of the thesis various types of boundary conditions for the steady state Stokes equations are considered. We formulate the boundary conditions in a new way, such that the boundary value problem becomes non-singular, and derive estimates of the solution. LÄS MER
2. Boundary integral methods for Stokes flow : Quadrature techniques and fast Ewald methods
Sammanfattning : Fluid phenomena dominated by viscous effects can, in many cases, be modeled by the Stokes equations. The boundary integral form of the Stokes equations reduces the number of degrees of freedom in a numerical discretization by reformulating the three-dimensional problem to two-dimensional integral equations to be discretized over the boundaries of the domain. LÄS MER
3. A Linearized Navier-Stokes Equations Methodology for Aeroacoustic and Thermoacoustic Simulations
Sammanfattning : Aeroengine noise is one of the dominating noise sources in today’s aircraft. Reduction of the aeroengine noise is related to multiphysics phenomena, and that is subject to different mechanisms, e.g., the coupling between turbulence, flame and sound waves. LÄS MER
4. Accuracy, efficiency and robustness for rigid particle simulations in Stokes flow
Sammanfattning : The thesis concerns simulation techniques for systems of nano- to micro-scaled rigid particles immersed in a viscous fluid, ubiquitous in nature and industry. With negligible fluid inertia, the set of PDEs known as the Stokes equations can be used to model the hydrodynamics. LÄS MER
5. Frequency Domain Linearized Navier-Stokes Equations Methodology for Aero-Acoustic and Thermoacoustic Simulations
Sammanfattning : The first part of the thesis focuses on developing a numerical methodology to simulate the acoustic properties of a hybrid liner consisting of a perforated plate, a porous layer and a Helmholtz cavity. Liners are always a standard way to reduce noise in today’s aeroengines, e.g. LÄS MER