Sökning: "geometri och analys Analys"

Visar resultat 31 - 35 av 51 avhandlingar innehållade orden geometri och analys Analys.

  1. 31. A Method for Dispersive Split Hopkinson Pressure Bar Analysis Applied to High Strain Rate Testing of Spruce Wood

    Författare :Svante Widehammar; Karl-Gustav Sundin; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; split Hopkinson; wave propagation; dispersion; Hamilton s principle; strain rate; calibration; spruce; wood; Materialvetenskap; Materials science; Teknisk materialvetenskap; teknisk fysik med inriktning mot hållfasthetslära; Technical Physics;

    Sammanfattning : En metod för dispersiv analys av försök med delad hopkinsonstång tillämpad på provning av granved vid hög töjningshastighetSyftet var att etablera en metod för att studera sambandet mellan spänning och töjning för granved vid hög töjningshastighet. Detta åstadkoms genom att anpassa och något vidareutveckla tekniken med delad hopkinsonstång ("Split Hopkinson Pressure Bar", SHPB). LÄS MER

  3. 32. Coherent structures and control in wall-bounded turbulent flows

    Författare :Marco Atzori; Philipp Schlatter; Ricardo Vinuesa; Oscar Flores; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulent boundary layers; numerical simulations; coherent structures; predetermined flow control.; Turbulenta gränsskikt; numeriska simuleringar; koherenta strukturer; förutbestämd flödeskontroll; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : This thesis is concerned with two distinct topics related to the study of wall-bounded turbulence: the connection between instantaneous three-dimensional coherent structures and mean-flow properties, and the development and analysis of pre-determined control techniques for adverse-pressure-gradient boundary layers.We examined regions with intense velocity fluctuations in various flowcases. LÄS MER

  4. 33. Integral equations and function extension techniques for numerical solution of PDEs

    Författare :Fredrik Fryklund; Anna-Karin Tornberg; Alex Barnett; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Matematik; Mathematics;

    Sammanfattning : Today many phenomena from science and engineering can be simulated accurately thanks to computational methods. Still, many challenges remain, one of them being close interface interactions when simulating e.g. the dynamics of a substance concentration in multiphase flows at the micro level. LÄS MER

  5. 34. Structure-acoustic analysis; finite element modelling and reduction methods

    Författare :Peter Davidsson; Byggnadsmekanik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mechanical engineering; hydraulics; vacuum technology; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; low frequency range; building acoustics; lightweight structures; porous materials; modal reduction; substructuring; finite element analysis; structural acoustics; vibroacoustics; Structural dynamics;

    Sammanfattning : This thesis investigates structure-acoustic systems by use of finite element analysis. The systems studied here are limited to those that consist of an enclosed acoustic fluid cavity, which is coupled to a flexible structure and/or a porous sound absorbing material domain. LÄS MER

  7. 35. Solar cavity receiver design for a dish-Stirling system

    Författare :Jorge Garrido Gálvez; Björn Laumert; Uwe Gampe; KTH; []
    Nyckelord :Concentrating Solar Power; Solar receiver; Solar simulator; Uncertainty analysis; Monte Carlo ray tracing; Experimental validation; Coatings; System modeling; Structural analysis; Creep damage; Thermal stress; Cavity receiver design; Energy Technology; Energiteknik;

    Sammanfattning : The growing concern for the climate change has led to an increasing research effort in renewable energy technologies in order to achieve a more sustainable electricity production. Concentrating Solar Power (CSP) is identified as a promising technology to deal with part of the future electricity production. LÄS MER