Sökning: "TECHNOLOGY Engineering physics Acoustics"

Visar resultat 1 - 5 av 105 avhandlingar innehållade orden TECHNOLOGY Engineering physics Acoustics.

  1. 1. Studies on Diesel sprays under non-reacting and reacting conditions

    Detta är en avhandling från Gothenburg : Chalmers tekniska högskola

    Författare :Chengjun Du; [2017]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; diffusion flame; OH radical; ethanol; spray vaporization; soot formation; cavitation; turbulent; OH* chemiluminescence; laser extinction; LAS; Diesel sprays;

    Sammanfattning : Methods for reducing engine-out emissions are urgently needed to mitigate climate change and air pollution. In diesel engines, the quality of fuel-air mixing and the subsequent combustion process strongly affect fuel efficiency and engine-out emissions. LÄS MER

  2. 2. Quantum acoustics with propagating phonons

    Detta är en avhandling från Gothenburg : Chalmers tekniska högskola

    Författare :Maria Ekström; [2020]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; superconducting circuits; qubit; interdigital transducer; artificial atom; unidirectional transducer; Surface acoustic wave; phonon; Electromagnetically Induced Transparency; phonon router; quantum acoustics;

    Sammanfattning : Surface acoustic waves (SAWs) are mechanical vibrations that propagate on the surface of solids while dissipating little power, consequently enabling them to propagate freely over long distances. The speed and wavelength of SAWs are reduced a five order of magnitude compared to when light is used as a carrier at gigahertz frequencies. LÄS MER

  3. 3. Numerical Simulations of Flows around Trains and Buses in Cross Winds

    Detta är en avhandling från Gothenburg : Chalmers tekniska högskola

    Författare :Hassan Hemida; [2008]
    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; winds; Trains and buses aerodynamics; LES; DES;

    Sammanfattning : When cruising in strong winds, ground vehicles can experience strong aerodynamic forces and moments that may increase drag, reduce their stability, generate noise and induce accidents in the case of strong side winds. However, prevention of the unwanted influences of side winds requires that the flow structures around vehicles are fully understood in both the instantaneous and time-averaged flow. LÄS MER

  4. 4. Aerodynamics of an Aeroengine Intermediate Compressor Duct: Effects from an Integrated Bleed System

    Detta är en avhandling från Gothenburg : Chalmers tekniska högskola

    Författare :Elias Siggeirsson; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbomachinery; CFD; SBES; Hybrid RANS LES; DDES; rotor off-take; S-shaped duct; Intermediate Compressor Duct; Bleed system; Dual-time-stepping;

    Sammanfattning : With the successful development of high-bypass-ratio turbofan engines, major aerodynamic components have been optimized and continuous efficiency improvements are getting harder to maintain. Therefore, to meet the requirements of lower emission of greenhouse gases, auxiliary modules such as intermediate ducts are receiving increasing interest. LÄS MER

  5. 5. On Noise Generation and Dynamic Transmission Error of Gears

    Detta är en avhandling från Stockholm : KTH

    Författare :Mats Henriksson; Leping Feng; Reader Andy Moorhouse; [2009]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TECHNOLOGY Engineering mechanics Vehicle engineering; TEKNIKVETENSKAP Teknisk mekanik Farkostteknik; TECHNOLOGY Engineering physics Acoustics; TEKNIKVETENSKAP Teknisk fysik Akustik;

    Sammanfattning : Noise from heavy trucks is an important environmental issue. Several sources contribute to the total noise level of a vehicle, such as the engine, gearbox, tires, etc. The tonal noise from the gearbox can be very disturbing for the driver, even if the noise level from the gearbox is lower than the total noise level. LÄS MER