Sökning: "pipe bend"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden pipe bend.

1. 1. Experimental study of turbulent flows through pipe bends

   Författare :Athanasia Kalpakli; P. Henrik Alfredsson; Ramis Örlü; Christoph Brücker; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulent flow; swirl; pulsation; pipe bend; hot-wire anemometry; cold-wire anemometry; laser Doppler velocimetry; stereoscopic particle image velocimetry.;

   Sammanfattning : This thesis deals with turbulent flows in 90 degree curved pipes of circular cross-section. The flow cases investigated experimentally are turbulent flow with and without an additional motion, swirling or pulsating, superposed on the primary flow. LÄS MER

3. 2. Studies of sound generation and propagation in flow ducts

   Författare :Fabrice Ducret; Mats Åbom; Andy Moorhouse; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; two-port; plane wave; HVAC system; tailpipe; exhaust system; flexible duct; pipe; reflection coefficient; impedance; flow noise; vorticity; damping; scaling laws; impedance; transmission loss; perforated plate; slit; non linearity; Acoustics; Akustik;

   Sammanfattning : This thesis contains three papers investigating problems of interest for noise control in ducts. The first part of this thesis treats the sound propagation in rectangular ducts with flexible walls. Various experimental techniques are performed to measure the internal sound propagation and radiation to the surrounding. LÄS MER

4. 3. 1D engine simulation of a turbocharged SI engine with CFD computation on components

   Författare :Ulrica Renberg; Hans-Erik Ångström; Laszlo Fuchs; Per Birkestad; KTH; []
   Nyckelord :1D modeling; CFD modeling; turbine efficiency; pipe flow; turbocharged engine; TECHNOLOGY; TEKNIKVETENSKAP;

   Sammanfattning : Techniques that can increase the SI- engine efficiency while keeping the emissions very low is to reduce the engine displacement volume combined with a charging system. Advanced systems are needed for an effective boosting of the engine and today 1D engine simulation tools are often used for their optimization. LÄS MER

5. 4. Numerical computations of the unsteady flow in a radial turbine

   Författare :Fredrik Hellström; Laszlo Fuchs; Jonas Bredberg; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Pulsatile flow; radial turbines; pipe flow; effects of inlet conditions; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : Non-pulsatile and pulsatile flow in bent pipes and radial turbine has been assessed with numerical simulations. The flow field in a single bent pipe has been computed with different turbulence modelling approaches. LÄS MER

7. 5. 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