Search for dissertations about: "grazing-bias flow"

Found 4 swedish dissertations containing the words grazing-bias flow.

2. 1. Experimental Determination of Aeracoustic Sources in Low Mach Number Internal Flows

   Author : Andreas Holmberg; Hans Bodén; Lars Enghardt; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aeracoustics; ducts; N-ports; scattering matrix; wave decomposition; source determination; over-determination; flow noise; fluid-acoustic interaction; fluid-structure-acoustic interaction; wave number; T-junction; power balance; grazing-bias flow; Acoustics; Akustik; Vehicle engineering; Farkostteknik;

   Abstract : In this thesis, the in-duct experimental methods for determining aeroacoustic N-ports of in-duct elements are discussed and improved. The scattering matrix determination methods and the related wave decomposition methods are evaluated from measurements in an empty duct carrying a mean flow. READ MORE

4. 2. Investigation of perforated mufflers and plates

   Author : Ying Guo; Mast Abom; Ragnar Glav; KTH; []
   Keywords : sound; perforated; micro-perforated; muffler; flow; hole; impedance; model; experiment;

   Abstract :     Mufflers are used in for instance exhaust system of cars or trucks to reduce noise. Perforated pipes are one of the main components of modern mufflers. To study acoustic properties of mufflers with perforated pipe is one of the main targets of this thesis. READ MORE

5. 3. 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

6. 4. Prediction of Thermo-Acoustic Properties in Combustion Chambers

   Author : Guillaume Jourdain; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : Design and analysis methods for gas turbine combustors or afterburners need to be improved in particular regarding the prediction of combustion instabilities. A methodology, which combines the use of a linearized flow solver and the Arnoldi algorithm for eigenmode extraction, resolves eigenmodes which are candidates to these instabilities. READ MORE