Sökning: "duct termination"

Hittade 5 avhandlingar innehållade orden duct termination.

  1. 1. Studies of flow duct acoustics with applications to turbocharged engines

    Författare :Hans Rämmal; Hans Boden; Mats Åbom; Antonio Torregrosa; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; IC-engine; turbocharger; duct termination; flow duct; exhaust system; inlet system; acoustic source; one-port; two-port; source model; transmission loss; two-port matrix; reflection coefficient; source strength; multi-load method; Acoustics; Akustik;

    Sammanfattning : A number of experimental and theoretical studies, performed in the field of technical flow duct acoustics are presented in this thesis. The acoustical methods treated are implemented on turbocharged IC-engines and engine gas exchange system components. A new method based on the well-known two-load technique has been developed. LÄS MER

  3. 2. Acoustic Characterization of Turbochargers and Pipe Terminations

    Författare :Heiki Tiikoja; Mats Åbom; Francisco Denia; KTH; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  4. 3. Methods for Modelling and Characterization of In-Duct Sources

    Författare :Hans Rämmal; Hans Bodén; Mats Åbom; Antonio Torregrosa; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Methods to characterize acoustic sources in flow ducts have been investigated. In the first part of this thesis a measurement procedure to characterize an air terminal device using an acoustic one-port source model based on the two microphone technique has been tested and validated. LÄS MER

  5. 4. 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

  7. 5. Synthesis and Characterization of Carbon Based One-Dimensional Structures : Tuning Physical and Chemical Properties

    Författare :HamidReza Barzegar; Thomas Wågberg; Hans Kuzmany; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Carbon Nanotube; single-walled carbon nanotube; nitrogen doped; chemical vapor deposition; fullerene; hybrid structures; nanomaterials; nanomaterial;

    Sammanfattning : Carbon nanostructures have been extensively used in different applications; ranging from electronic and optoelectronic devices to energy conversion. The interest stems from the fact that covalently bonded carbon atoms can form a wide variety of structures with zero-, one- and two-dimensional configuration with different physical properties. LÄS MER