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Recently, the comfort of urban environment has caught more and more attention, in this study, the main research focus will be the influence of the array penetrate strength of urban architecture on pedestrian wind field. Luotung township of Yilan county which has more even urban architecture height will be used as the main research target, and CFD method will be used as the research method, finally, accompanied with the on-site measurement data, the accuracy of CFD numerical simulation is proved. Motorcycle mobile measurement method will be adopted, and the measurement was conducted on July at Luotung township, which has the most serious summer hot island effect, meanwhile, through on-site measurement, the seriousness of the hot island situation in Luotung township is understood. The CFD architecture model is performed with grid division simplification, and simplification rule is made. The urban architecture scale is divided into 2.5m×2.5m, 5m×5 m and 10m×10m for simplification, through CFD, it was found that in addition to grid division, urban fabric needs to be referred to, meanwhile, original urban fabric needs to be preserved so as to simulate grid simplified 5m×5m-R that is closest to the original drawing. Moreover, simplified 5m×5m-R model is used to perform the simulation of how urban architecture influences pedestrian wind field, and the following two simulations are adopted: (1) Different average height 3F, 5F, 7F, 10F on-site climate condition simulations; (2) Experiments of different incident wind angles. In the investigation of the simplification of CFD model simulation, it was found that lots of factors need to be listed in the urban fabric investigation except on-site architecture dimension. The following three results are obtained from the experimental results: (1) The influence of architecture height on the penetrate rate of urban air circulation; (2) The investigation of penetrate level for the wind incidence at different incident angles into the city; (3) The influence of wind incidence angle on pedestrian wind field at different road width. It was found from the research that 1m/s-3m/s low wind speed belongs to penetrating wind type, wind speed above 5m/s belongs to non-penetrating wind type. In the analysis of different angles, when the wind speed is below 3m/s (or in the range of 1m/s-2m/s), the air flow penetration rate in the entire region will be more uniform, for wind speed in the range of 3m/s-6m/s, the reduction will be larger, when the wind speed is above 7m/s or 8m/s, the reduction will become more significant, however, since the wind speed is larger, certain multiplication effect can be seen. In the road width analysis, 40 m road will be helpful to the flow of wind in the road, it was also found that in the inner layer area, the air circulation rate is significantly insufficient, and inner circumference area and outer circumference area will then be generated within the area wind field. The result of this research can be used as reference on the urban wind field review or new urban planning and designing by the future urban planner.
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