Search for dissertations about: "Engineering Acoustics"

Showing result 6 - 10 of 972 swedish dissertations containing the words Engineering Acoustics.

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

    Author : Hassan Hemida; Chalmers tekniska högskola; []
    Keywords : 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;

    Abstract : 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. READ MORE

  4. 7. Spray combustion with multiple-injection in modern engine conditions

    Author : Ahmad Hadadpour; Strömningsteknik; []
    Keywords : 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; Spray combustion; Multiple-injection; Internal combustion engine; LES; FGM; ESF;

    Abstract : Combustion of fuel in diesel engines emits substances harmful to the environment such as soot. These emissions can be reduced by either in-cylinder treatments or after-treatments. One of the common in-cylinder treatments is multiple-injection, which divides a single fuel injection to multiple smaller injections. READ MORE

  5. 8. Propeller-Hull Interaction Effects in Calm Water and Regular Head Waves

    Author : Mohsen Irannezhad; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; RANS; Resistance; Thrust Deduction Factor; Self-Propulsion Point of Model; CFD; Regular Head Waves; Nominal Wake; Ship Motions; Taylor Wake Fraction; Propeller Open Water Characteristics; EFD; FNPF;

    Abstract : In order to design fuel-efficient ships and install compatible propulsion systems, ship and propeller designers need to know the potential effects of the interactions between different ship components, e.g., hull, propeller, appendages and machinery, on the ship performance at sea. READ MORE

  6. 9. Numerical investigation of tonal noise sources from centrifugal fan

    Author : Martin Ottersten; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Computational Aeroacoustics; Tonal Noise; Centrifugal Fan; Blade Passing Frequency;

    Abstract : Heating, ventilating, and air conditioning systems (HVAC) are today an important part of many people's life. They provide a sufficient amount of airflow with the correct temperature, quality, and humidity. The negative side is the noise it produces. Many improvements have been made in building development to reduce noise from the environment. READ MORE

  7. 10. Energy in supermarkets - An overview on the energy flows and refrigeration controls

    Author : Tommie Månsson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : The electrical energy used by supermarkets represents approximately 3% of Sweden's annual energy use. Of this, the refrigeration system accounts for 50%. To reduce greenhouse gases introduced by energy generation, a larger share of renewable energy sources must be implemented. READ MORE