臺北盆地都市微氣候觀測與模擬

Micro-scale urban meteorological observation and simulation in Taipei basin

梅可忠(Ko-Chung Mei)

指導教授 ： 林博雄

國立臺灣大學/理學院/大氣科學研究所/碩士(2012年)

https://doi.org/10.6342/NTU.2012.01503

摘要

高層建築與摩天大樓是都市的地標，也是都市微氣象研究可利用的平台。從2011年1月開始，本研究在臺北101大樓的34F（151公尺）和82F（352公尺）的露台上安裝WXT520微型氣象感測器，進行長時間的都市垂直方向的定點密集觀測。此外，我們也在臺灣大學校園施放了34次探空氣球觀測（距臺北101金融大樓3公里）加以同步比較。
數據分析結果顯示，34F和82F之間的逐時氣象差值顯示了日變化和季節變化特徵，並觀測到34F層風速大於82F風速；從相同高度的探空氣球資料也發現，自由大氣的風速大於101大樓的風速。除此之外，不少的探空資料確實顯示臺北盆地350公尺處有低層強風的現象，同時，我們也分析了2011年的近地面逆溫現象與個案。
本研究也透過AutoCAD軟體以及高空間解析度的計算流體力學數值模式（Cradle Stream Model）來模擬101大樓周圍大規模的風場。模擬結果顯示，建築群會使得迎風面與背風面風速降低，而在大樓的兩側與上方風速增加，但是觀測和模擬的風速遞減比例有所不同。

關鍵字

邊界層 ； 臺北盆地 ； 臺北101大樓 ； 流體力學數值模式 ； 都市微氣候

並列摘要

High buildings (skyscraper) are the significant landmarks of urban cities. In this study, we conducted an intensive meteorological observation at Taipei 101 building to take the vertical in-situ observation.
Starting from January of 2011, the minute-resolution observations through WXT520 integrated weather sensors were installed on the 34F (151m) and 82F (352m) balcony, started from January of 2011 until now. In addition, there were 34 radiosonde observations at NTU campus (3-km away of Taipei 101) for validation of skyscraper observations.
The analysis shows that the deviation of air temperature between 34F and 82F captures the characteristics of boundary temperature inversion very well. The diurnal and seasonal variation of temperature and humidity field can also be seen from the hourly data. The wind speed at 34F layer is significantly larger than 82F from WXT520, compared with the wind speed from radiosonde observations, the wind speed is also smaller at Taipei 101 at the same altitude.
Meanwhile, cases with strong temperature inversion are analyzed in this study. AutoCad software and a high resolution CFD model (Cradle Stream Model) are used to simulate the micro-scale wind field surrounding Taipei 101. The simulations showed that the wind speed decreases in front of and behind the building and behind the building, and increases on the sides. The decreasing ratio of wind speed from observation and simulation is not consistent with each other.More simulations from different wind directions were established to provide an corrected reference on wind field observations on Taipei 101 balconies.

並列關鍵字

Boundary layer ； Taipei basin ； Taipei 101 ； Stream Model ； Micro-scale urban meteorology

參考文獻

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