Search for dissertations about: "aero acoustics"

Showing result 16 - 20 of 29 swedish dissertations containing the words aero acoustics.

  2. 16. Geometry parameterisation and response surface-based shape optimisation of aero-engine compressors

    Author : Jörgen Burman; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strömningslära; Fluid Mechanics;

    Abstract : The main goal in jet engine design is to achieve light, compact and highly efficient systems while reducing the cost and design times. Traditionally, the design has been based on trial-and-error procedures, which count on the skills and experience of the designer to suggest design improvements. READ MORE

  4. 17. Large Eddy Simulation of Turbulent Compressible Jets

    Author : Bernhard Semlitsch; Mihai Mihaescu; Laszlo Fuchs; Paul G. Tucker; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Compressible Flow; Large Eddy Simulation; Acoustic Noise Generation; Near-field Acoustics; Flow Control; Optimization; Modal Flow Decomposition; Engineering Mechanics; Teknisk mekanik;

    Abstract : Acoustic noise pollution is an environmental aggressor in everyday life. Aero- dynamically generated noise annoys and was linked with health issues. It may be caused by high-speed turbulent free flows (e.g. READ MORE

  5. 18. A study of incompressible flow fields for computational aero acoustics

    Author : Jonas Ask; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : .... READ MORE

  6. 19. Aerodynamic Design and Optimization of Intermediate Ducts for High By-pass Ratio Jet Engines

    Author : Fredrik Wallin; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Intermediate transition ducts; vortex generators; S-shaped ducts; response surface methodology; source term model; optimization;

    Abstract : Demands on improved efficiency and reduced noise levels cause a strive toward high by-pass ratio commercial aero engines. This results in multi-spool aero engines with small high-pressure ratio cores and large fans. The low-pressure system has a lower rotational speed and a larger radius than the high-pressure core system. READ MORE

  7. 20. Thermo-Acoustic Properties in Combustion Chambers

    Author : Guillaume Jourdain; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mode Stability Analysis; Computational Aeroacoustics; Screech mode; Arnoldi s Method; Buzz mode; Afterburner; Gas turbine combustor; Combustion instabilities;

    Abstract : Design and analysis methods for gas turbine combustors or afterburners have to be improved in particular regarding the prediction of combustion instabilites. A methodology, which combines the use of a linearized flow solver and an Arnoldi algorithm performing the eigenmode extraction procedure, resolves eigenmodes which are candidates to these instabilities. READ MORE