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  1. 1. Fibre flow mechanisms

    Författare :Roger Bergström; Ulf Björkman; Bo Norman; Mark Martinez; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fibre flow; floc; shear; compression; fibre network; stress chain; Cellulose and paper engineering; Cellulosa- och pappersteknik;

    Sammanfattning : The flow behaviour, and primarily the floc-floc interaction, of pulp paper suspensions have been studied visually. Analogy models based on these observations have been developed as well as the identification of important parameters of floc break-up in low shear rate flow fields. LÄS MER

  3. 2. Modelling and measurement of velocity and concentration in fibre-gas suspensions

    Författare :Olof Melander; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; particle transport; fibre suspensions; two-fluid model; particle image velocimetry; fibres; concentration measurement; computational fluid dynamics; multiphase flow;

    Sammanfattning : .... LÄS MER

  4. 3. Near wall fibre orientation in flowing suspensions

    Författare :Allan Carlsson; Daniel Söderberg; Fredrik Lundell; Helge I. Andersson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluid mechanics; fibre orientation; shear flow; wall effect; fibre suspension; papermaking; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : This thesis deals with fibre orientation in wall-bounded shear flows. The primary application in mind is papermaking. The study is mainly experimental,but is complemented with theoretical considerations.The main part of the thesis concerns the orientation of slowly settlingfibres in a wall-bounded viscous shear flow. LÄS MER

  5. 4. Modelling and simulation of paper structure development

    Författare :Stefan B Lindström; Tetsu Uesaka; Myat Htun; Cyrus Aidun; Mittuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Forming; Fibre; Paper; Fibre suspension; Paper structure; Simulation; Rheology; Chemical engineering; Kemiteknik; Engineering physics; Teknisk fysik;

    Sammanfattning :      A numerical tool has been developed for particle-level simulations of fibre suspension flows, particularly forming of the fibre network structure of paper sheets in the paper machine. The model considers inert fibres of various equilibrium shapes, and finite stiffness, interacting with each other through normal, frictional, and lubrication forces, and with the surrounding fluid medium through hydrodynamic forces. LÄS MER

  7. 5. Laser Doppler Perfusion Monitoring and Imaging especially as regards testing for sympathetic nerve function

    Författare :Carolin Freccero; Kirurgi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Physiology; wavelength; sympathetic vasodilatation; sympathetic vasoconstriction; sympathetic nerve function; parasympathetic nerve function; laser Doppler perfusion imaging; laser Doppler perfusion monitoring; finger skin blood flow; fibre separation; contralateral cooling; Concentration; Fysiologi; Cardiovascular system; Kardiovaskulära systemet; Diagnostik; Diagnostics;

    Sammanfattning : The operating principle of all laser Doppler methods is based on the fact that incident photons shift in wavelength when interacting with moving blood cells passing through the microvascular network. After photodetection and further signal processing, the recorded parameter can be considered an arbitrary measure of tissue blood flow, and this is referred to as ?perfusion?. LÄS MER