Sökning: "Boundary condition"
Visar resultat 1 - 5 av 242 avhandlingar innehållade orden Boundary condition.
1. Simulations of turbulent boundary layers with suction and pressure gradients
Sammanfattning : The focus of the present licentiate thesis is on the effect of suction and pressure gradients on turbulent boundary-layer flows, which are investigated separately through performing numerical simulations.The first part aims at assessing history and development effects on adverse pressure-gradient (APG) turbulent boundary layers (TBL). LÄS MER
2. Wave Splitting and Effective Boundary Conditions for Structural Elements
Sammanfattning : The subject of this thesis is twofold. The first part concerns the wave splitting of structural elements. The second part concerns approximate boundary conditions for fluid-loaded thin plates. Wave splitting is a mathematical tool for the formulation of scattering problems in the time domain that aims at solving inverse problems, e. LÄS MER
3. Optimisation and control of boundary layer flows
Sammanfattning : Both optimal disturbances and optimal control are studied by means of numerical simulations for the case of the flat-plate boundary-layer flow. The optimisation method is the Lagrange multiplier technique where the objective function is the kinetic energy of the flow perturbations and the constraints involve the linearised Navier–Stokes equations. LÄS MER
4. Boundary Conditions for Spectral Simulations of Atmospheric Boundary Layers
Sammanfattning : An atmospheric boundary layer (ABL) is generally a very high Reynolds number boundary layer over a fully rough surface that is influenced by different external forces. Numerical simulations of ABLs are typically demanding, particularly due to the high Reynolds numbers. LÄS MER
5. Rough surfaces in contact : artificial intelligence and boundary lubrication
Sammanfattning : Interacting surfaces are found in mechanical systems and components. Since engineered surfaces are not perfectly smooth, only a fraction of the nominal surface area is actually in contact. This fraction is denoted as the real area of contact, Ar, and is formed by the sum of the contact spots between the two touching surfaces. LÄS MER