Search for dissertations about: "duct flow"

Showing result 11 - 15 of 90 swedish dissertations containing the words duct flow.

2. 11. Aeroacoustics Studies of Duct Branches with Application to Silencers

   Author : Mikael Karlsson; Mats Åbom; Luc Mongeau; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; silencer; muffler; confined flows; flow duct; aeroacoustics; vortex sound; acoustic multiports; linear stability; self-sustained oscillations; whistling; Herschel-Quincke tube; acoustic resonator; Fluid mechanics; Strömningsmekanik;

   Abstract : New methodologies and concepts for developing compact and energy efficient automotive exhaust systems have been studied. This originates in the growing concern for global warming, to which road transportation is a major contributor. READ MORE

4. 12. Studies of sound generation and propagation in flow ducts

   Author : Fabrice Ducret; Mats Åbom; Andy Moorhouse; KTH; []
   Keywords : 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;

   Abstract : 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. READ MORE

5. 13. Experimental studies of large particles in Newtonian and non-Newtonian fluids

   Author : Sagar Zade; Luca Brandt; Fredrik Lundell; Ellen Longmire; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulence; finite-size; particle-laden flows; duct flow; pipe flow; viscoelastic fluid; viscoplastic fluid; Engineering Mechanics; Teknisk mekanik;

   Abstract : In everyday human life, laminar flow is arguably an exception whereas turbulent flow is the norm. Yet, the former has been much better understood, naturally since laminar flow renders itself to treatment in a relatively easier fashion compared to turbulence with its chaotic dynamics across multiple scales in space and time. READ MORE

6. 14. Acoustic Characterization of Turbochargers and Pipe Terminations

   Author : Heiki Tiikoja; Mats Åbom; Francisco Denia; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; acoustical two-port; turbocharger; transmission loss; sound generation; compressor; turbine; IC-engine; inlet system; exhaust system; flow duct; duct termination; reflection coefficient;

   Abstract : In search for quieter engines there is a need for a better understanding of the acoustic properties of engine intake and exhaust system components. Besides mufflers which have the purpose of reducing pressure pulses originating from the internal combustion (IC) engine, there are many components in a modern car exhaust and intake system, e.g. READ MORE

7. 15. Innovative noise control in ducts

   Author : Maaz Farooqui; Mats Åbom; Hans Bodén; Tamer Elnady; Jeong-Guon Ih; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Locally resonant materials; slow sound; acoustic impedance; metallic foam; low frequency noise; mufflers; lined ducts; grazing flow; flow duct; impedance eduction.; Vehicle and Maritime Engineering; Farkostteknik;

   Abstract : The objective of this doctoral thesis is to study three different innovative noise control techniques in ducts namely: acoustic metamaterials, porous absorbers and microperforates. There has been a lot of research done on all these three topics in the context of duct acoustics. READ MORE