Sökning: "canyon model"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden canyon model.

  1. 1. Sound propagation to two-dimensional shielded urban areas: a numerical and scale model study of façade treatments

    Författare :Maarten Hornikx; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; urban street canyon; scale model study; urban noise abatement schemes; road traffic noise; parabolic equation; equivalent sources model; 2.5-D geometry;

    Sammanfattning : .... LÄS MER

  3. 2. Dispersion and Transformation of Traffic Exhaust Particles in the Urban Atmosphere

    Författare :Matthias Ketzel; Kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; condensation; deposition; dilution; particle size distribution; plume model; street canyon; traffic pollution; urban environment; turbulence; aerosol dynamics modelling; coagulation; Physics; Fysik; Fysicumarkivet A:2004:Ketzel;

    Sammanfattning : Ultrafine particles, their sources and fate in the atmosphere are currently key issues in atmospheric research owing to concern about their effects on human health and global climate. Traffic emissions are a dominating source of ultrafine particles, especially in urban areas. LÄS MER

  4. 3. Numerical modelling of sound propagation to closed urban courtyards

    Författare :Maarten Hornikx; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; courtyard; urban noise abatement schemes; pseudospectral; road traffic noise; equivalent sources method; scale model study; urban canyon;

    Sammanfattning : Because modern urban environments suffer from excessive levels of road traffic noise, access to closed courtyards is essential in order to offer urban sound environments of high quality with regard to health and perceived sound. To reach this quality, which is described by the quiet side definition, the 24-hour equivalent noise level should be below 45 dB(A). LÄS MER

  5. 4. Numerical study on flow and pollutant dispersion inside street canyons

    Författare :Yang Yunkai; Martinac Ivo; Peng Shia-Hui; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flow; Pollutant dispersion; CFD; Street canyon; Reliability; SRA - Energy; SRA - Energi;

    Sammanfattning : This thesis analyzes the characteristics of flow pattern and vehicle-emitted pollutant dispersion in roughness surface layer. In an urban environment, wind flow and transported-pollutant source interfere strongly with buildings and other roughness elements on the surface ground, which results in complex characteristics of flow pattern and pollutant dispersion in 3D circumstances. LÄS MER

  7. 5. Prediction of Traffic Noise Shielding by City Street Canyons

    Författare :Mikael Ögren; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Reducing the sound level on the exposed building facades due to traffic noise in cities is difficult and expensive. Creating access for the inhabitants to a quiet side can be an alternative method for reducing the annoyance. Therefore it is of interest to predict the level on shielded positions such as courtyards. LÄS MER