Sökning: "Grid Code"

Visar resultat 16 - 20 av 59 avhandlingar innehållade orden Grid Code.

  1. 16. Computational hydrodynamics applied to an America's Cup class keel - best practice and validation of methods

    Författare :Sofia Werner; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CFD; America s Cup; induced drag; wind tunnel; winglet; validation; keel; vortex drag; wake survey;

    Sammanfattning : Numerical predictions of the flow around yacht keels can be performed with various types of methods. In this work computational fluid dynamic (CFD) computations are validated against wind tunnel studies of an America's Cup Class keel with the purpose of investigating the accuracy that can be achieved with CFD, which methods that are suitable and how they should be used in the best way. LÄS MER

  3. 17. Development of a Free Surface Capability in a RANS Solver with Coupled Equations and Overset Grids

    Författare :Michal Orych; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; free-surface; overset; RANS;

    Sammanfattning : This thesis is a result of investigations carried out during the implementation of a free surface capturing method in a RANS solver. The work consists of two distinct parts which complement each other, and the purpose is to improve the free surface interface sharpness and to reduce numerical diffusion of the gravity waves. LÄS MER

  4. 18. A New Paradigm for Large Brushless Hydrogenerators : Advantages Beyond the Static System

    Författare :Jonas Kristiansen Nøland; Urban Lundin; Phil Mellor; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Brushless exciters; Rotating exciters; Permanent Magnet Machines; Synchronous Generator Excitation; Thyristor Rectifiers; Chopper Rectifiers; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Sammanfattning : The grid code, FIKS, from the Norwegian transmission system operator (TSO), Statnett, states that synchronous generators > 25MVA, must have a static excitation system. However, an improved brushless excitation system is in operation on some commercial power plants (36MVA, 93.75rpm & 52MVA, 166. LÄS MER

  5. 19. Development of Effective Algorithm for Coupled Thermal-Hydraulics – Neutron-Kinetics Analysis of Reactivity Transient

    Författare :Joanna Peltonen; Tomas Lefvert; Paolo Vinai; KTH; []
    Nyckelord :Light Water Reactor; BWR; RELAP5; PARCS; Coupling TH NK; Mapping; Spatial Refinement; Turbine Trip; Feedwater Transient; Control Rod Drop; Reactor Stability;

    Sammanfattning : Analyses of nuclear reactor safety have increasingly required coupling of full three dimensional neutron kinetics (NK) core models with system transient thermal-hydraulics (TH) codes. To produce results within a reasonable computing time, the coupled codes use different spatial description of the reactor core. LÄS MER

  7. 20. Boundary Conditions for Spectral Simulations of Atmospheric Boundary Layers

    Författare :Erik Boström; Philipp Schlatter; Bernard J. Geurts; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    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