Sökning: "Järnvägsgruppen - Ljud och vibrationer"

Visar resultat 1 - 5 av 9 avhandlingar innehållade orden Järnvägsgruppen - Ljud och vibrationer.

  1. 1. Nano-Engineered Contrast Agents : Toward Multimodal Imaging and Acoustophoresis

    Författare :Satya V.V.N. Kothapalli; Dmitry Grishenkov; Lars-Åke Brodin; Andreas Michael Versluis; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nano-engineered microbubbles; SPION nanoparticles; Acoustic characterization of MBs; Fracturing mechanism of MBs; Opto-acoustics; Acoustophoresis; Physics; Fysik; Järnvägsgruppen - Ljud och vibrationer; Järnvägsgruppen - Ljud och vibrationer; Teknik och hälsa; Technology and Health;

    Sammanfattning : Diagnostic ultrasound (US) is safer, quicker and cheaper than other diagnostic imaging modalities. Over the past two decades, the applications of US imaging has been widened due to the development of injectable, compressible and encapsulated microbubbles (MBs) that provide an opportunity to improve conventional echocardiographic imaging, blood flow assessment and molecular imaging. LÄS MER

  3. 2. Modeling of sound-turbulence interaction in low-Mach-number duct flows

    Författare :Chenyang Weng; Mats Åbom; Susann Boij; Avraham Hirschberg; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Järnvägsgruppen - Ljud och vibrationer; Järnvägsgruppen - Ljud och vibrationer;

    Sammanfattning : When sound waves propagate in a duct in the presence of turbulent flow, tur- bulent mixing can cause extra attenuation of the sound waves in addition to that caused by the viscothermal eects. Experiments show that compared to the vis- cothermal eects, turbulent absorption becomes the dominant contribution to the sound attenuation at suciently low frequencies. LÄS MER

  4. 3. Statistical energy analysis and variational principles for the prediction of sound transmission in multilayered structures

    Författare :Mathias Barbagallo; Svante Finnveden; Jean-Louis Guyader; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; statistical energy analysis; porous materials; biot theory; variational principles; hamilton principle; double walls; multilayered structures; Järnvägsgruppen - Ljud och vibrationer; Järnvägsgruppen - Ljud och vibrationer;

    Sammanfattning : Multilayered structures have many application in industry and society: they have peculiar properties and serve a variety of purposes, like structural support, thermal insulation, vibrational and acoustic isolation. This thesis concerns the prediction of sound transmission in multilayered structures. LÄS MER

  5. 4. Interface Damping: Characterization and Implementation

    Författare :Ravi Varma Nadampalli; Peter Göransson; Bert Pluymers; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Järnvägsgruppen - Ljud och vibrationer; Järnvägsgruppen - Ljud och vibrationer;

    Sammanfattning : Material damping in a structure is well defined and documented. However, dissipation due to mechanical contact (surface contact) in a complex built-up structure is not as well represented, in particular in large scale noise and vibration simulations. LÄS MER

  7. 5. Rotating Structure Modeling and Damping Measurements

    Författare :Jia Sun; Leif Kari; Damian Vogt; Ulf Orrenius; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustics; Akustik; Vehicle engineering; Farkostteknik; Järnvägsgruppen - Ljud och vibrationer; Järnvägsgruppen - Ljud och vibrationer;

    Sammanfattning : The structural damping is of importance to suppress the vibration amplitude of compressor blades rotating at high angular velocity under a high cycle impact. To avoid the appearance of the high cycle fatigue (HCF), damping materials may be applied to the compressor blades. LÄS MER