Sökning: "Susann Boij"

Visar resultat 6 - 10 av 15 avhandlingar innehållade orden Susann Boij.

  1. 6. Frequency Domain Linearized Navier-Stokes Equations Methodology for Aero-Acoustic and Thermoacoustic Simulations

    Författare :Wei Na; Gunilla Efraimsson; Susann Boij; Martinez Lera Paula; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Linearized Navier-Stokes Equations; frequency domain; fluid equivalent model; hybrid liner; thermoacoustic instabilities; Rijke-tube; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : The first part of the thesis focuses on developing a numerical methodology to simulate the acoustic properties of a hybrid liner consisting of a perforated plate, a porous layer and a Helmholtz cavity. Liners are always a standard way to reduce noise in today’s aeroengines, e.g. LÄS MER

  3. 7. Noise emissions from sustainable transport : A multi-scale modeling approach

    Författare :Johan Nygren; Susann Boij; Romain Rumpler; Ciarán J. O'Reilly; Eoin King; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Traffic simulation; sustainable transport; environmental noise; vehicle acoustics; energy efficiency; Trafiksimulering; hållbar transport; samhällsbuller; fordonsakustik; energieffektivitet; Farkostteknik; Vehicle and Maritime Engineering;

    Sammanfattning : Noise emissions from transportation remain one of the greatest environmental issues of modern day. Inhabitants in urban environments are especially exposed, with almost 80 million people in the European Union exposed to noise levels exceeding the recommended limits set by the World Health Organization (WHO). LÄS MER

  4. 8. On the impact of noise and energy demand from traffic : An assessment using microscopic modelling

    Författare :Johan Nygren; Susann Boij; Romain Rumpler; Ciarán J. O'Reilly; Arnaud Can; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Traffic simulation; sustainable transport; noise emissions; environmental impact; energy efficiency; Trafiksimulering; hållbar transport; buller; miljöpåverkan; energieffektivitet; Vehicle and Maritime Engineering; Farkostteknik;

    Sammanfattning : Noise emissions from transportation remain one of the greatest environmental issues of modern day. Inhabitants in urban environments are especially exposed, with almost 80 million people in the European Union exposed to noise levels exceeding the recommended limits set by the World Health Organization (WHO). LÄS MER

  5. 9. Assessing precision and accuracy in acoustic scattering matrix measurements

    Författare :Luck Peerlings; Hans Bodén; Susann Boij; Avraham Hirschberg; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aero-acoustics; sudden area expansion; in-duct acoustics; acoustic scattering matrix; impedance tube; uncertainty analysis; systematic errors; Vehicle and Maritime Engineering; Farkostteknik;

    Sammanfattning : Acoustic scattering matrices are used to characterize the influence of inline duct elements on the acoustic wave propagation in wave guides.When measuring the properties of these matrices, errors are always present in the results and need to be characterized to make valid statements on the correspondence between model predictions and measurements. LÄS MER

  7. 10. Methods and techniques for precise and accurate in-duct aero-acoustic measurements : Application to the area expansion

    Författare :Luck Peerlings; Susann Boij; Hans Bodén; Yves Aurégan; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Area-expansion; Scattering matrix; Multi-microphone method; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : During the design and commissioning of combustion equipment, combustion associated instabilities are commonly encountered. These thermo-acoustic instabilities can cause undesirable noise, vibrations, local thermal and mechanical stresses in the combustor and are prominent in lean combustion. LÄS MER