Search for dissertations about: "wave phenomena ducts"

Found 3 swedish dissertations containing the words wave phenomena ducts.

  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. Acoustic scattering in ducts and influence of flow coupling

    Author : Susann Boij; KTH; []
    Keywords : sound; vortex sheet; flow separation; end correction; Strouhal number; non-orthogonal modes; energy balance; TECHNOLOGY; TEKNIKVETENSKAP;

    Abstract : The subject of this thesis is the acoustic properties offlow duct area expansions and the influence of flow-acousticcoupling at sharp edges. For low Mach number flow, significantinteraction between the sound field and the flow field canoccur at such points of flow separation. READ MORE

  5. 3. Acoustic In-duct Characterization of Fluid Machines with Applications to Medium Speed IC-engines

    Author : Antti Hynninen; Mats Åbom; Hans Bodén; Antonio Torregrosa; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; in-duct; acoustic source; source characterization; IC-engine;

    Abstract : The unwanted sound, noise, can lead to health problems, e.g. hearing loss and stress-related problems. A pre-knowledge of noise generation by machines is of great importance due to the ever-shorter product development cycles and stricter noise legislation. READ MORE