Sökning: "steady state solutions"

Visar resultat 1 - 5 av 48 avhandlingar innehållade orden steady state solutions.

  1. 1. An experimental investigation of flow in a Kaplan runner steady-state and transient

    Detta är en avhandling från Luleå : Luleå tekniska universitet

    Författare :Kaveh Amiri; Luleå tekniska universitet.; [2014]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strömningslära; Fluid Mechanics;

    Sammanfattning : Water turbines are since some years widely used for grid stabilization purposes according to their exceptional load variation capability which gives them the ability to compensate grid fluctuations initiated by the customer’s consumption or intermittent electricity production systems such as wind and solar power. Different renewable power generation technologies can be combined in mini-grids to electrify isolated villages and extend existing grid networks. LÄS MER

  2. 2. Realistic simulations of delta wing aerodynamics using novel CFD methods

    Detta är en avhandling från Stockholm : KTH

    Författare :Stefan Görtz; KTH.; [2005]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; CFD; aerodynamics; flow physics; steady; unsteady; delta wing; vortical flow; Rymd- och plasmafysik; NATURAL SCIENCES Physics Geocosmophysics and plasma physics Space physics; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Rymdfysik;

    Sammanfattning : The overall goal of the research presented in this thesis is to extend the physical understanding of the unsteady external aerodynamics associated with highly maneuverable delta-wing aircraft by using and developing novel, more efficient computational fluid dynamics (CFD) tools. More specific, the main purpose is to simulate and better understand the basic fluid phenomena, such as vortex breakdown, that limit the performance of delta-wing aircraft. LÄS MER

  3. 3. Active heat capacity : models and parameters for the thermal performance of buildings

    Detta är en avhandling från Byggnadsfysik LTH, Lunds Tekniska Högskola

    Författare :Gudni Jóhannesson; [1981]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Time domain solutions; RC-models; Admittance; Frequency response; Simplified models; Non-steady state; Building heat transfer; värmeflöden; transienta förlopp; byggnader; beräkningsmodeller;

    Sammanfattning : The thesis concerns the characterization and evaluation of nonsteady heat transfer in building components and building enclosures. The major aim of the underlaying research has been to assemble and develop simplified calculation procedures for this purpose. LÄS MER

  4. 4. Mathematical modelling approach to collective decision-making

    Detta är en avhandling från Uppsala : Department of Mathematics

    Författare :Natalia Zabzina; Uppsala universitet.; [2017]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; collective behaviour; collective decision-making; communication mechanisms; positive feedback; mathematical modelling; bifurcation phenomena; steady state solutions; symmetry breaking; symmetry restoring; diffusion-limited aggregation; fractal dimension;

    Sammanfattning : In everyday situations individuals make decisions. For example, a tourist usually chooses a crowded or recommended restaurant to have dinner. Perhaps it is an individual decision, but the observed pattern of decision-making is a collective phenomenon. LÄS MER

  5. 5. Convergence Acceleration for Flow Problems

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Henrik Brandén; Uppsala universitet.; Uppsala universitet.; [2001]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Computational fluid dynamics; convergence acceleration; semicirculant preconditioning; fundamental solutions; Numerical Analysis; Numerisk analys;

    Sammanfattning : Convergence acceleration techniques for the iterative solution of system of equations arising in the discretisations of compressible flow problems governed by the steady state Euler or Navier-Stokes equations is considered. The system of PDE is discretised using a finite difference or finite volume method yielding a large sparse system of equations. LÄS MER