在台灣，超高樓之開發行對於周圍環境之流場的改變，因此環境影響評估作業準則中，風場（行人舒適度）應進行相關之模擬分析與風洞試驗。
本研究主要利用計算流體力學軟體（fluent 6.3）與風洞試驗進行比較。主要分成兩個部分：
（1）兩棟獨立高樓。就風洞試驗：主要使用熱膜探針與Irwin probes進行量測；數值模擬分析：使用標準紊流模式（standard κ-ε）、經修正紊流模式（renormalization Groups κ-ε）、LES (large eddy simulation)、DES（detached eddy simulation）。以DES模擬結果最好，平均風速誤差為9％，有效風速的誤差為17％。
（2）選定台中市七期重劃區。採用standard κ-ε紊流模式、RNG κ-ε紊流模式與LES紊流模式進行模擬預測。數值模擬預測與風洞試驗的結果：
（a）16個方向無因次化平均速度的數值模擬（standard κ-ε紊流模式）預測與風洞試驗之相關性（correlation）介於0.53～0.91，平均值為0.81；（b）62個數值模擬測點與風洞試驗相互比較之下，其平均誤差約為20～30％；（c）若使用西安大略大學(university of Western Ontario)舒適度評估準則[2-24][2-41]，數值模擬預測與風洞試驗的趨勢是一致的，但風洞試驗的結果則較為保守；（d）LES紊流模式模擬結果會優於standard κ-ε與RNG κ-ε紊流模式且LES紊流模式的預測會較為保守；必須考慮模擬所需要的時間。（e）若使用丁育群、朱佳仁所建議的舒適度評估準則[2-41]，都符合宜人的狀況，因此數值模擬預測與風洞試驗的結果變得更好；但此評估方法是較為不保守，容易造成大樓興建後會產生較高的風速，因而造成行人感受到不舒適的情形發生。

The scientific and technological development allowed higher and higher buildings to be constructed causing serious wind acceleration on the ground. High-rise buildings tend to change the pedestrian wind environment and caused discomfort to the pedestrians or even pose threat to their safety in this area. Therefore, the Environmental Impact Assessment Act in Taiwan and Taipei Public Space Management Practices stipulated that the wind tunnel experiments for the assessment of the pedestrian comfort must be carried out prior to the construction of the high-rise buildings.
This study utilized the computational fluid dynamics (CFD) software for simulation and prediction, and compared the results with the wind tunnel experiments. The study involved two isolated buildings and the wind field evaluation of complex terrain in cities. 
In the wind tunnel experiments, the ground level wind velocity was measured by hot-film probes and Irwin probes. In the numerical simulation analysis, the standard κ-ε turbulence model, RNG κ-ε turbulence model, LES turbulence model and DES turbulence model were adopted.
 For the two isolated buildings, the error of the mean velocity of the detached eddy simulation and the wind tunnel experiments was 9% and the error of the effective velocity was 17%.
In the complex urban terrain of the Taichung, for the steady-state of the standard κ-ε turbulence model and the wind tunnel experiments in 16 directions, the correlation coefficient ranged between 0.51 and 0.92 and the average was 0.81.The mean error of the dimensionless wind velocity was 20~30%. If the comfort criterion of the university of Western Ontario for pedestrian wind were adopted, the tendencies of the CFD prediction and the wind tunnel experiments were consistent to a considerable extent. The LES turbulence model was the best prediction of standard κ-ε turbulence model and RNG κ-ε turbulence model, but it would take a lot of time to simulate. If used the comfort criterion of the 
Yu-Chun Ting and Chia-Jen Chu, the ranked evaluation of all locations were pleasant. This comfort criterion would not be conservative and could cause the high velocity after the tall building was constructed.

目錄
第一章 緒論	1
1-1 前言	1
1-2 研究動機	2
1-3 研究方法與內容	3
第二章 文獻回顧	5
2-1 都市氣候與社區微氣候評估	5
2-1-1 熱島效應	5
2-1-2 社區微氣候評估	5
2-1-3 亂流擴散	7
2-2 平均風速剖面分佈	7
2-2-1對數律風速剖面	7
2-2-2指數律風速剖面	8
2-2-3 紊流強度	9
2-3 風流經結構體的行為	11
2-4 建築物風場特性	13
2-5 都市複雜地形幾何建立	19
2-5-1 數值地形圖的取得	19
2-5-2 VBA for Autocad	21
2-5-3 點座標資料擷取	22
2-5-4 建築物幾何形狀建立	25
2-6 數值模擬	28
2-6-1 CFD介紹	28
2-6-2 紊流模式	30
2-7 舒適度評估標準	37
2-8 行人風環境之現況發展	43
第三章 實驗設置與量測方法	46
3-1風洞簡介	46
3-2 風洞內模擬實驗之相似性法則	47
3-3大氣邊界層流場之模擬	50
3-4 TSI定溫熱膜探針之率定	53
3-5 壓力轉換器之率定	54
3-6 地表風速量測器	55
3-7 多頻道電子式風壓掃描器	56
第四章 兩棟獨立高樓之結果與討論	58
4-1 實驗設置	58
4-2 數值模擬的介紹	60
4-3 風洞試驗	62
4-4 風洞試驗與數值模擬分析	65
第五章 都市複雜地形	71
5-1 風洞試驗	71
5-2 數值模擬分析	72
5-2-1 幾何形狀建立	72
5-2-2 網格繪製	72
5-3 台中氣象資料分析	75
5-3-1氣象資料分析流程	75
5-3-2氣象資料的結果	77
5-4 風洞試驗與數值模擬比較	84
5-4-1 網格獨立性測試	84
5-4-2 無因次化平均風速比較（北風）	85
5-4-3 無因次化平均風速比較（西風）	91
5-4-4 無因次化平均風速比較（東北東風）	94
5-4-5 無因次化平均風速比較（北北西風）	96
5-4-6 紊流模式相關性的比較	98
5-4-7 Large eddy simulation模擬預測（北風）	101
5-4-8 Large eddy simulation模擬預測（南風）	106
5-4-9 行人舒適性評估	109
第六章 行人舒適度評估之建議	119
6-1 風洞模擬之行人舒適度調查	119
6-2 實場之行人舒適度調查	120
6-3 行人舒適度評估建議值	123
6-3-1 各國行人舒適度的比較	123
6-3-2 本國舒適度的建議值	131
第七章 結論與展望	136
7-1 氣象資料分析：	136
7-2 幾何形狀建立：	137
7-4 網格繪製	137
7-5 紊流模式的選擇	138
7-6行人舒適度的評估與選擇：	139
7-7 數值模擬的應用：	140
7-8 未來展望：	141
參考文獻	143

圖目錄
圖2- 1紊流邊界層內方形建築物之周遭流場結構（WOO,1976）	13
圖2- 2 迎風面渦旋(自行研究)	14
圖2- 3 建築物尾流(自行研究)	15
圖2- 4 穿堂風(自行研究)	16
圖2- 5角隅強風(自行研究)	16
圖2- 6 遮蔽效應(自行研究)	17
圖2- 7縮流效應(自行研究)	18
圖2- 8台中數值地形	20
圖2- 9 GOOGLE EARTH所提供衛星空照	20
圖2- 10 擷取座標之表單設	24
圖2- 11點座標資料	24
圖2- 12 表單輸出紀錄檔	26
圖2- 13 紀錄檔之文字內容	26
圖2- 14 周遭建築物之幾何形狀的建立	27
圖3- 1 淡江大學大氣邊界層風洞實驗室	47
圖3- 2錐形擾流板及阻牆	52
圖3- 3粗糙元素	52
圖3- 4邊界層ZΔ值，風洞試驗段之高度與錐形擾流板寬度的關係	53
圖3- 5 IRWIN PROBE	56
圖3- 6多頻道壓力訊號處理系統(RADBASE3200)	57
圖4- 1 量測點位置	59
圖4- 2 風洞試驗	59
圖4- 3 風速剖面	61
圖4- 4 結構性網格	61
圖4- 5 風速剖面	62
圖4- 6熱膜探針與IRWIN PROBES之相關性	64
圖4- 7熱膜探針與IRWIN PROBES之誤差值	64
圖4- 8風洞試驗與數值模擬之相關性	67
圖4- 9風洞試驗與數值模擬之誤差值（平均風速）	68
圖4- 10風洞試驗與數值模擬之相關性	69
圖4- 11風洞試驗與數值模擬之誤差值（平均風速）	69
圖4- 12風洞試驗與數值模擬之誤差值（有效風速）	70
圖5- 1風洞試驗模型	73
圖5- 2風洞試驗量測位置點	73
圖5- 3網格品質警示	74
圖5- 4非結構性網格	74
圖5- 5 機率分布與偉伯函數迴歸（北北東～南風）	78
圖5- 6機率分布與偉伯函數迴歸（南南西～北風）	79
圖5- 7 台中市各風向平均風速	80
圖5- 8 台中市各風向發生機率	80
圖5- 9台中市各風向韋伯函數迴歸K值	81
圖5- 10台中市各風向韋伯函數迴歸C值	81
圖5- 11 網格細化之相關性	88
圖5- 12 北風無因化風速的比較	89
圖5- 13 點位置圖（北風）	89
圖5- 14 等無因次化平均風速（北風且高度為1.8公尺）	90
圖5- 15 風洞試驗與數值模擬預測之相關性	92
圖5- 16西風無因化風速的比較	92
圖5- 17點位置圖（西風）	93
圖5- 18等無因次化平均風速（西風且高度為1.8公尺）	93
圖5- 19東北東風無因化平均風速的比較	95
圖5- 20 風洞試驗與數值模擬分析之誤差值	95
圖5- 21北北西風無因化風速的比較	97
圖5- 22 不同紊流模式之相關性	99
圖5- 23 北風無因次化平均風速	100
圖5- 24北北西風無因次化平均風速	100
圖5- 25 LES與STANDARD Κ-Ε紊流模式比較	103
圖5- 26 風洞試驗與數值模擬分析之相關性比較（平均風速）	104
圖5- 27 風洞試驗與數值模擬分析之相關性（有效風速）	105
圖5- 28 風洞試驗與數值模擬之誤差值	105
圖5- 29 LES與STANDARD Κ-Ε紊流模式比較	107
圖5- 30風洞試驗與數值模擬分析之相關性比較（平均風速）	107
圖5- 31風洞試驗與數值模擬分析之相關性（有效風速）	108
圖5- 32風洞試驗評估的結果	111
圖5- 33值模擬評估的結果(STANDARD Κ-Ε)	112
圖5- 34數值模擬評估的結果(RNG Κ-Ε)	113
圖5- 35數值模擬評估的結果(LES)	114
圖5- 36風洞試驗評估的結果	116
圖5- 37數值模擬評估的結果(STANDARD Κ-Ε、RNG Κ-Ε、LES)	117
圖5- 38宜人臨界值，實驗與數值模擬預測發生累積機率之相關性	118
圖6- 1 各國行人舒適度的比較[6-3]	125
圖6- 2 行人舒適度的比較	130
圖6- 3 短時間停留有效風速與發生機率（林晟漢）	133
圖6- 4短時間停留有效風速與發生機率（淡江大學風工程中心）	133
圖6- 5快步行走區有效風速與發生機率（林晟漢）	134
圖6- 6快步行走區有效風速與發生機率（淡江大學風工程中心）	134
表目錄
表2- 1不同地形下，Α、ZΔ值的變化	9
表2- 2不同地形下，Z0、Β值的變化	11
表2- 3風之效應（蒲福風級）	40
表2- 4舒適性評估準則[2-24]、[2-41]	41
表2- 5 住宅區的行人風場評估標準[2-41]	41
表2- 6 商業區及工業區的評估標準[2-41]	42
表2- 7加拿大RWDI公司的行人舒適度評估標準[2-42]	42
表6- 1舒適度標準比較	122
表6- 2 每小時等值風速與發生機率	126
表6- 3 陣風風速與發生機率	126
表6- 4 淡江大學行人舒適度評估準則建議值	135

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