Search for dissertations about: "SOUND ABSORPTION COEFFICIENT"

Found 5 swedish dissertations containing the words SOUND ABSORPTION COEFFICIENT.

  2. 1. Glass mat reinforced thermoplastics - material, process and selected applications

    Author : Jan Wahlberg; Industriell Produktion; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Material technology; recycling; sound absorption; energy absorption; vibrational energy; microtension; processing; Glass fibre; thermoplastics; Materiallära; materialteknik;

    Abstract : The work presented in this thesis covers the processing of glass mat reinforced thermoplastics, GMT, and the mechanical properties of this material group. The thesis evaluates the possibilities of the material group from a processing and mechanical properties point of view. READ MORE

  4. 2. Studies of sound generation and propagation in flow ducts

    Author : Fabrice Ducret; Mats Åbom; Andy Moorhouse; KTH; []
    Keywords : 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;

    Abstract : 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. READ MORE

  5. 3. 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

  6. 4. Foam, Fire and Free Volume - Chemical and Physical Aspects of Porous Polymers

    Author : Anna Andersson; Centrum för analys och syntes; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Poisson ratio; vibration damping; acoustic impedance; cell morphology; hyperbranched polymer; Polymer foams; free volume; positron annihilation; supercritical fluid.;

    Abstract : Automotive seating has been under continous development since it was described for the first time in 1885. At that time one could read about a “padded leather bench seat sitting on springs mounted directly to the frame of a horse-less carriage”. READ MORE

  7. 5. Extension of PC-SAFT to model inhomogeneous and transport properties

    Author : Gulou Shen; Georgios Kontogeorgis; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Energy Engineering; Energiteknik;

    Abstract : CO2 separation plays an important role in greenhouse gas emission mitigation, in bio-fuel production via biomass gasification as well as in biogas upgrading. The current CO2 separation technologies are energy intensive, and new cost-effective CO2 separation technologies are needed. READ MORE