Search for dissertations about: "CAA"

Showing result 1 - 5 of 25 swedish dissertations containing the word CAA.

  2. 1. Chemical substitution with a life cycle perspective: The case of per- and polyfluoroalkyl substances in durable water repellents

    Author : Hanna Holmquist; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; LCIA; CAA; LCA; PFAS; DWR;

    Abstract : The aim of the research presented in this thesis was to support the process of substitution of side-chain fluorinated polymers in durable water repellents (DWRs), that give rise to emissions of hazardous per- and polyfluoroalkyl substances (PFASs). The focus was on: i) the provision of improved decision support regarding the environmental and human health performance of alternatives, and ii) public readiness for substitution and what messages can motivate consumers to voluntary substitution. READ MORE

  4. 2. A Study of Mach 0.75 Jets and Their Radiated Sound Using Large-Eddy Simulation

    Author : Niklas Andersson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Jet noise; CAA; LES; Large Eddy Simulation; Computational Aero-Acoustics;

    Abstract : Large-Eddy Simulations (LES) of a compressible nozzle/jet configuration have been carried out. Two jets were simulated, an isothermal jet and a jet with a higher temperature than the surrounding air. The Mach number was in both cases 0.75 and the jet Reynolds number was 50,000. READ MORE

  5. 3. A Study of Subsonic Turbulent Jets and Their Radiated Sound Using Large-Eddy Simulation

    Author : Niklas Andersson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Two-Point Space-Time Correlations; CAA; Jet Noise; LES; Kirchhoff; Coaxial Jets; Heated Jets; Aeroacoustics;

    Abstract : Stricter noise regulation for near-ground operations has made noise reduction in commercial aircraft a topic of growing interest in the aerospace industry. To meet airworthiness requirements new noise reduction technologies have to be developed and numerical methods for correct assessment of these technologies are desirable. READ MORE

  6. 4. Predictions of Aerodynamically Induced Wind Noise Around Ground Vehicles

    Author : Jonas Ask; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; side mirror; LES; incompressibility; Curle; CAA; air rush noise; low Mach number; ground vehicle; cavity;

    Abstract : Over the last decade wind noise has with few exceptions consistently generated a constant or even growing level of customer complaints to automotive companies world-wide. This can partly be explained by a relatively greater focus on engine, power-train and tire noise combined with a growing need to reduce weight in future cars. READ MORE

  7. 5. Numerical Simulations of Noise Reduction Devices for Aero Engines

    Author : Haukur Hafsteinsson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustic liner; G3D; CAA; CFD; CD-nozzle; LES;

    Abstract : Increasing air traffic and denser population around airports have led to stricterregulations on aircraft noise. The engine is the main source of noise of jet aircraft.Decreasing jet engine noise can in some cases reduce sonic fatigue andthereby increase the engine lifetime. READ MORE