Sökning: "stabilitetsanalys"

Visar resultat 1 - 5 av 7 avhandlingar innehållade ordet stabilitetsanalys.

  1. 1. Toward Realistic Failure Evaluations for Concrete Buttress Dams

    Författare :Jonas Enzell; Anders Ansell; Erik Nordström; Andreas Sjölander; Richard Malm; Leif Lia; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; concrete dams; buttress dams; stability analysis; dam failure behavior; physical model tests; FEM; betongdammar; lamelldammar; stabilitetsanalys; dammbrott; fysiska modellförsök; FEM; Betongbyggnad; Concrete Structures;

    Sammanfattning : Concrete dams, complex structures supporting massive loads, have traditionally been assessed using simplified 2D analytical stability analyses based on the rigid body assumption. Previous studies have shown that 3D behavior, such as the interaction between the monoliths and the valley's geology, can greatly impact the load-bearing capacity of gravity dams but remains largely unexplored in buttress dams. LÄS MER

  3. 2. Space-adaptive simulation of transition and turbulence in shear flows

    Författare :Daniele Massaro; Philipp Schlatter; Saleh Rezaeiravesh; Alfredo Pinelli; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulence; global stability; coherent structures; adaptive mesh refinement; Turbulens; global stabilitet; koherenta strukturer; adaptiv nätförfining; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : Transitional and turbulent shear flows are ubiquitous, from the boundary layer developing on an aeroplane wing to the flow within the aortic arch. In this thesis, we study wall-bounded and free shear flows through direct numerical simulations. LÄS MER

  4. 3. Topology optimization of transitional flows

    Författare :Harrison Nobis; Dan Henningson; Philipp Schlatter; Paolo Luchini; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct Numerical Simulation; Topology Optimization; Laminar– Turbulent Transition; Spectral Element Method; Direkt numerisk simulering; topologioptimering; laminär–turbulent omslag; spektralelementmetod; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : 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. LÄS MER

  5. 4. Behaviour and stability of shallow underground constructions

    Författare :Jimmy Töyrä; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mining and Rock Engineering; Gruv- och Berganläggningsteknik;

    Sammanfattning : The growing needs of urbanization, like more transport possibilities, sewers, maintenance tunnels, the need of constructing shallow tunnels increase. By a better understanding of the mechanical properties and state of stress in the shallow parts of the bedrock it may be possible to determine which factors that are of importance at a specific construction site, and thereby increase the cost efficiency of pre-investigations and the tunnel construction. LÄS MER

  7. 5. Linear and non-linear dynamics of non-autonomous flows

    Författare :J. Simon Kern; Dan S. Henningson; Ardeshir Hanifi; Peter J. Schmid; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Time-dependent flows; linear stability; non-linear dynamics; Floquet analysis; optimally time-dependent modes; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : Fluid flows subject to time-dependent external forces or boundary conditions are ubiquitous in biology and technical applications. Whether one considers birds flying by flapping their wings or the gust response of wind turbines, the flow is non-autonomous. LÄS MER