The effect of street fabric to Wind environment simulation in urban street canyon

• Main Authors: Wan-ChenLin, 林宛貞
• Other Authors: Han-Liang Lin
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/75181301695351080621

碩士 === 國立成功大學 === 都市計劃學系 === 103 === Under the influence of the urban heat island effect, street ventilation has gradually become a more serious issue in recent urban planning in order to improve environmental quality of urban life. For this reason, many academic researches particularly investigated the relationship between street canyons’ aspect ratio and street ventilation plus airflow field. As time progresses, compared to the time-consuming and expensive wind tunnel simulation, advance of computation technology and the gradual expansion of the academic research level has made computational Fluid Dynamics (CFD) a more suitable tool in academic research. In addition to consideration of the building aspect ratio, the external environment itself has become an important factor in wind environment. However, parameter used in CFD analysis varies from study to study and lacks standardization. Therefore this study will take (1)simulation model size and (2)internal environment under consideration and investigate the impact of the above factors on the simulated street canyon environment. Then verify the result of the simulation model with the actual result. For these reasons, Tainan City West Central Dist Minsheng Road, which starts from Sec.2 Ximen Road to Sec.3 Guohua Street is selected as a representative of the grid road system Qingnian road, which starts from Tang De-Jhang Memorial Park to Sec.1Minquan Road will be the representative of the radial road system. The study period will be summer afternoon, using movable measurement and CFD numerical simulation to figure out the impact of different model external environment size and street fabric on wind speed simulation results. Analysis of the result of CFD numerical simulation found that both external environment and radius size of the simulation model have a direct impact on the street canyon wind speed distribution in the two research areas. The lower wind speed of the radial road system in the center street canyon compare to the grid road system shows a more difficult airflow. Results shown that speed of the center street canyon appear to be more stabilized after the radius of the radial street model gradually reached 400 meter while that of the grid road system demands more than a radius of 500 meters.