Sökning: "Inflow generation"

Visar resultat 1 - 5 av 19 avhandlingar innehållade orden Inflow generation.

  1. 1. Inflow generation for scale-resolving simulations of turbulent boundary layers

    Författare :Timofey Mukha; Mattias Liefvendahl; Gunilla Kreiss; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Beräkningsvetenskap med inriktning mot numerisk analys; Scientific Computing with specialization in Numerical Analysis;

    Sammanfattning : Generating inflow fields for scale-resolving simulations of turbulent flow is crucial for a wide range of applications and is an active area of research. In this thesis, a method for inflow generation employing a precursor turbulent channel flow simulation is proposed. LÄS MER

  3. 2. Modelling Techniques for Large-Eddy Simulation of Wall-Bounded Turbulent Flows

    Författare :Timofey Mukha; Mattias Liefvendahl; Hrvoje Jasak; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Wall modelling; Inflow generation; Large-eddy simulation; OpenFOAM; Computational fluid dynamics; Scientific Computing; Beräkningsvetenskap;

    Sammanfattning : Large-eddy simulation (LES) is a highly accurate turbulence modelling approach in which a wide range of spatial and temporal scales of the flow are resolved. However, LES becomes prohibitively computationally expensive when applied to wall-bounded flows at high Reynolds numbers, which are typical of many industrial applications. LÄS MER

  4. 3. Stochastic Modeling and Optimization under Uncertainty of a Hydro Power System

    Författare :Roger Halldin; Matematisk statistik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Statistik; actuarial mathematics; programming; operations research; Statistics; energy derivatives; multistage stochastic programs; electricity prices; principal component analysis; Scenario trees; inflow modeling; operationsanalys; programmering; aktuariematematik;

    Sammanfattning : Electricity bought and sold on the deregulated Nordic power market is dominated by hydro power. However, hydro power generation is restricted by the amount of water in reservoirs. The inflows to these reservoirs show a yearly cycle and seasonal planning of the production is necessary. Seasonal planning up to 1. LÄS MER

  5. 4. A Method for the Study of Unsteady Cavitation - Observations on Collapsing Sheet Cavities

    Författare :Johannes Schöön; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cloud cavitation; re-entrant jet; cavitation erosion; gust generation; cavitation;

    Sammanfattning : When subjected to sufficiently low pressures, water will eventually come apart. Gas-filled cavities appear in the water: it is said to cavitate. When the cavities collapse, they often do so quite vigorously, causing noise, vibrations and erosion. A well-known example of cavitation is that found on heavily loaded ship propellers. LÄS MER

  7. 5. Karaktäristiken hos strukturmarken på olika altitud i Abiskoområdet – en koppling till klimat och komplex systemteori

    Författare :Gunnar Scharin; Christer Jonasson; Johan Kling; Uppsala universitet; []
    Nyckelord :Abisko; patterned ground; permafrost; non-sorted circles; altitude; self-generation; Geovetenskap med inriktning mot miljöanalys; Earth Science with specialization in Environmental Analysis; Earth Science with specialization in Physical Geography; Geovetenskap med inriktning mot naturgeografi; Biology with specialization in Ecological Botany; Biologi med inriktning mot ekologisk botanik;

    Sammanfattning : Subarctic and alpine areas are sensitive to climatic change when they lie at the margin of permafrost occurrence. Patterned ground in such areas is generated from an interplay among different mechanisms such as temperature, hydrology, soil texture, snow cower and vegetation. LÄS MER