Sökning: "Knud Meyer"

Hittade 3 avhandlingar innehållade orden Knud Meyer.

  1. 1. 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

  3. 2. Dynamics of Exhaust Valve Flows and Confined Bluff Body Vortex Shedding

    Författare :Marcus Winroth; P. Henrik Alfredsson; Knud Erik Meyer; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : This thesis can be divided into two interconnected topics; engine exhaust-valve flows and confined bluff-body vortex shedding. When optimising engine flow systems it is common to use low order simulation tools that require empirical inputs, for instance with respect to flow losses across the exhaust valves. LÄS MER

  4. 3. On Gas Dynamics of Exhaust Valves

    Författare :Marcus Winroth; P. Henrik Alfredsson; Ramis Örlü; Knud Erik Meyer; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Exhaust valve; poppet valve; dynamic valve; engine modeling; discharge coefficient; Avgasventil; rörlig ventil; motorsimulering; utsläppskoefficient; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : With increasing effects of global warming, efforts are made to make transportationin general more fuel efficient. When it comes to internal combustion engines,the most common way to improve fuel efficiency is through ‘downsizing’. Downsizingmeans that a smaller engine (with lower losses and less weight) performsthe task of a larger engine. LÄS MER