Sökning: "curved pipes"

Visar resultat 1 - 5 av 13 avhandlingar innehållade orden curved pipes.

  1. 1. Shapes of pipes

    Författare :Valerio Lupi; Philipp Schlatter; Ramis Örlü; Jean-Christophe Robinet; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Global stability; curved pipes; secondary flow; wall-bounded turbulence; Global stabilitet; krökta rör; sekundärflöde; turbulens; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : Curved pipes are ubiquitous in several industrial applications and biological systems. The study of flows through these configurations is therefore of significant practical interest.In the present thesis, the modal stability of flows in both toroidal and spatially developing bent pipes is investigated to understand the onset of transition. LÄS MER

  3. 2. Vortices in turbulent curved pipe flow-rocking, rolling and pulsating motions

    Författare :Athanasia Kalpakli Vester; P. Henrik Alfredsson; Ramis Örlü; Nils Tillmark; Knud Meyer; KTH; []
    Nyckelord :Turbulence; curved pipes; swirling flow; pulsatile flow; time-resolved stereoscopic particle image velocimetry; hot-wire anemometry; proper orthogonal decomposition; turbocharger;

    Sammanfattning : This thesis is motivated by the necessity to understand the flow structure of turbulent flows in bends encountered in many technical applications such as heat exchangers, nuclear reactors and internal combustion engines. Flows in bends are characterised by strong secondary motions in terms of counter-rotating vortices (Dean cells) set up by a centrifugal instability. LÄS MER

  4. 3. Large Eddy Simulations of Complex Flows in IC-Engine's Exhaust Manifold and Turbine

    Författare :Johan Fjällman; Laszlo Fuchs; Mihai Mihaescu; Ricardo Martinez-Botas; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Large Eddy Simulations; Reynolds Averaged Navier-Stokes; Turbocharger; Turbine; Curved Pipes; Pulsatile Flow; Proper Orthogonal Decomposition; Large Eddy Simulations; Reynolds Averaged Navier-Stokes; Turboladdare; Turbin; Rörkrök; Pulserande Flöde; Proper Orthogonal Decomposition; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : The thesis deals with the flow in pipe bends and radial turbines geometries that are commonly found in an Internal Combustion Engine (ICE). The development phase of internal combustion engines relies more and more on simulations as an important complement to experiments. LÄS MER

  5. 4. Mathematical modelling of flow through thin curved pipes with application to hemodynamics

    Författare :Arpan Ghosh; Vladimir Kozlov; Matts Karlsson; David Rule; Grigory Panasenko; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : The problem of mathematical modelling of incompressible flows with low velocities through narrow curvilinear pipes is addressed in this thesis. The main motivation for this modelling task is to eventually model the human circulatory system in a simple way that can facilitate the medical practitioners to efficiently diagnose any abnormality in the system. LÄS MER

  7. 5. Novel Thermal Insulation in Future Building and District Heating Applications - Hygrothermal Measurements and Analysis

    Författare :Axel Berge; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vacuum insulation panels; superinsulation; aerogel blankets; wooden stud walls; thermal conductivity; district heating;

    Sammanfattning : The interest for reducing the energy consumption in society has increased during the last decades due to an increased environmental awareness. One way to decrease the energy losses in the building sector is to improve the thermal insulation of building envelopes and installations and thereby decrease the heat losses. LÄS MER