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Found 5 swedish dissertations matching the above criteria.
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1. Direct numerical simulations of the rotating-disk boundary-layer flow
Abstract : This thesis deals with the instabilities of the incompressible boundary-layer flow that is induced by a disk rotating in otherwise still fluid. The results presented are mostly limited to linear instabilities derived from direct numerical simulations (DNS) but with the objective that further work will focus on the nonlinear regime, providing greater insights into the transition route to turbulence. READ MORE
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2. Spectral-element simulations of turbulent wall-bounded flows including transition and separation
Abstract : The spectral-element method (SEM) is used to study wall-bounded turbulent flowsin moderately complex geometries. The first part of the thesis is devoted to simulations of canonical flow cases, such as temporal K-type transitionand turbulent channel flow, to investigate general resolution requirements and computational efficiency of the numerical code nek5000. READ MORE
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3. Direct Numerical Simulation of Boundary-layer Transition with Free-stream Turbulence
Abstract : This thesis considers the generation and influence of free-stream turbulence toboundary layer transition on both flat and curved bodies in the flow. Variousflow configurations such as flow around the flat plate with a sharp leading edgeand low-pressure turbine blades are considered. READ MORE
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4. Topology optimization of transitional flows
Abstract : This thesis is concerned with the application of topology optimization in thedesign of structures that control fluids. A framework is developed in the high-order Spectral Element Method (SEM) code Nek5000, extending Nek5000 fromits original capabilities, performing Direct Numerical Simulations (DNS), toperforming density-based topology optimization. READ MORE
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5. CFD Study of Molten Pool Convection in a Reactor Vessel during a Severe Accident
Abstract : During severe accidents in nuclear reactors, the core and internal structures can melt down and relocate into the reactor pressure vessel (RPV) lower head (LH) forming there a stratified molten corium pool. The pool generally consists of superheated oxidic and metallic liquid layers imposing thermo-mechanical loads on the RPV wall. READ MORE