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| 題 名 | 隧道內污染擴散傳播模式之發展與應用=Development and Application of Pollutants Dispersion Model in a Traffic Tunnel |
|---|---|
| 作 者 | 仲崇毅; 鍾佩伶; | 書刊名 | 大仁學報 |
| 卷 期 | 28 民95.03 |
| 頁 次 | 頁37-50 |
| 分類號 | 445.63 |
| 關鍵詞 | 隧道; 數值模擬; 空氣污染物; Traffic tunnel; Numerical model; Air pollutants; |
| 語 文 | 中文(Chinese) |
| 中文摘要 | 本研究應用四階Runge-Kutta法求解隧道內風速分佈。配合濃度方程式以Crank-Niclson隱性差分法建立隧道一維非穩態流場及濃度場模擬模式。另外藉由空氣動力學的分析,考慮紊流作用效應,探討隧道控制體積內氣流之三維流動型態與空氣污染物擴散現象,應用有限體積法建構交通隧道三維數值模式,將車輛污染物排放視為隧道地面之線污染源,利用標準k-ε模式紊流模式推估隧道內紊流效應,模擬分析交通隧道內通風效應及氣態污染物擴散分佈情形,探討噴流風扇及車行活塞效應對隧道內氣流之影響以及對氣態污染物之稀釋效率,並分析隧道內污染物之空間分佈特性,同時探討一維及三維模式模擬隧道內流場及污染物傳輸現象之差異。 研究結果顯示當隧道內風扇全部關閉時,軸向風速僅受車行效應作用,隧道內風速可視為等速分佈,此現象在三維模式模擬結果與一維模式之假設近似。但風扇啟動後,隧道內氣流會受風扇啟動數目及風扇位置等因素而改變,軸向風速則不再維持等速分佈,隧道內污染濃度會沿車行方向逐漸累積升高,當風扇關閉時,此傳輸現象尤為明顯。當風扇關閉時,隧道內軸向濃度呈現近乎線性累積現象,但當風扇啟動後,軸向濃度會因風扇吹出氣流之影響而呈現起伏變化。另外,隧道內污染濃度會沿車行方向逐漸累積升高,且隧道斷面上污染濃度會呈現濃度分層現象。 |
| 英文摘要 | One-dimensional and Three-dimensional numerical modeling on the aerodynamics of airflow and dispersion of air pollutants in a longitudinal-ventilated traffic tunnel were carried out. To establish the models, ventilation fans, friction losses, traffic flow rate, speed, emission factor and piston effect of moving vehicles were taken into consideration. Turbulent flow and dispersion of gaseous pollutants in road tunnels were solved numerically using the finite volume method in three-dimensional model. Traffic emissions were accordingly modeled as banded line sources along the tunnel floor. The effects of fan ventilation, roughness and piston effect of moving vehicles on the air flow and pollutant dilution are examined. Case study was conducted on the Cross-Harbor Tunnel in which on-site measurements of traffic flow were also conducted concurrently to provide traffic emission data to the tunnel environment for numerical simulation and comparisons. The results show that the major emission sources of CO are passenger cars and motorcycles. Pollutants convert downstream with the wind generated either by longitudinal ventilation fans and/or moving vehicles, thus causing increasing pollutants concentrations with increasing downstream distance. |
本系統中英文摘要資訊取自各篇刊載內容。