Sökning: "mean flow"

Visar resultat 16 - 20 av 451 avhandlingar innehållade orden mean flow.

  1. 16. Flow and Mixing of Pulp Suspensions

    Författare :Johan Pettersson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; flow behaviour; boundary-layer; Medium Consistency MC ; mixing; yield stress; suspension; pulp; Laser Doppler Anemometry LDA ; turbulence; fibre;

    Sammanfattning : When producing pulp and paper, pulp suspensions are treated in a number of unit operations at medium consistency (MC) concentrations (3-15% by weight). Pulp suspensions at these concentrations behave as solids at low shear rates, but at sufficiently high shear rates they start to flow and can even be made to act as water. LÄS MER

  3. 17. Characterization of Starch Using Flow Field-Flow Fractionation Techniques

    Författare :Catalina Fuentes; Avdelningen för livsmedel och läkemedel; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : To improve the properties and functionality of starch, it is important to understand the physicochemical and structural characteristics as raw material, after being modified to increase its characteristics and/or during changes due to the processing conditions. For this reason, the objective of the present thesis is to improve the understanding of characteristics and molecular properties like molar mass (M), root-mean-square radius (rrms) and their relation to other physicochemical properties of starch extracted from different sources. LÄS MER

  4. 18. An Experimental Study of Fluid Dynamics and Mixing in Bubbly Gas-Liquid Flow Systems

    Författare :Jafar Sadegh Moghaddas; Livsmedelsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Bubbly flow; PLIF; Two-phase flow; PIV; Gases; plasmas; Gaser; fluid dynamics; fluiddynamik; plasma; Mixing;

    Sammanfattning : In the present project, a new experimental method enabling Planar Laser-Induced Fluorescence (PLIF) measurements in bubbly gas-liquid flows is presented. Due to reflection and refraction of the laser light, the bubbles will cause an uneven and unknown distribution of light intensity in the measurement plane. LÄS MER

  5. 19. 4D flow MRI and modelling to assess cerebral arterial hemodynamics : method development and evaluation, with implementation in patients with symptomatic carotid stenosis

    Författare :Madelene Holmgren; Anders Eklund; Jan Malm; Anders Wåhlin; Sara Qvarlander; Ronnie Wirestam; Umeå universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; 4D flow MRI; carotid stenosis; cerebral blood flow; cerebral arterial compliance; cerebrovascular resistance; circleof Willis; computational fluid dynamics; magnetic resonance imaging; stroke; vascular disease; Neurology; neurologi;

    Sammanfattning : Blood flow measurements are important for understanding the development of cerebrovascular diseases. With 4D flow magnetic resonance imaging (4D flow MRI), simultaneous velocity measurements are obtained in all cerebral arteries in a scan of about ten minutes. However, 4D flow MRI is a relatively new technique. LÄS MER

  7. 20. Simulations of turbulent boundary layers with suction and pressure gradients

    Författare :Alexandra Bobke; Philipp Schlatter; Ramis Örlü; Ayse Gul Gungor; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; boundary layers; near-wall turbulence; history effects; asymptotic suction boundary layers; large-eddy simulation;

    Sammanfattning : The focus of the present licentiate thesis is on the effect of suction and pressure gradients on turbulent boundary-layer flows, which are investigated separately through performing numerical simulations.The first part aims at assessing history and development effects on adverse pressure-gradient (APG) turbulent boundary layers (TBL). LÄS MER