應用CFD軟體進行八卦山隧道火災煙流模擬之研究

A Simulation Study on Ba-Gua Mountain Tunnel Fire Hazard and Smoke Flow Using CFD Software

易逸波(Y. P. I) ； 黃奕豪(Y. H. Huang) ； 施威任(W. J. Shih) ； 宋鴻祥(H. H. Sung)

《鑛冶：中國鑛冶工程學會會刊》 55卷1期 (2011/03) Pp. 83-94

https://doi.org/10.30069/MM.201103.0007

摘要

當長隧道內發生大火時，由於外氣供給受到限制，隧道內將產生大量濃煙，因其空間之封閉性，導致濃煙排放相當困難，故濃煙是造成隧道內人員傷亡之最大元兇。本文以目前台灣第二長之八卦山公路隧道做為探討對象，對該隧道使用FDS火災模擬軟體進行1：1全尺度隧道火災模擬。由研究結果得知，若為了節省模擬時間及計算量，僅截取中間一段來模擬長隧道之火災行為，將會造成相當大之誤差。另外當火災發生時，將對向隧道通風皆改成往隧道內送氣的方式，對阻止濃煙進入對向隧道會有很大的幫助。藉由改變中央豎井軸流式風機及隧道內噴流式風機之通風方式及風機開啟數目，將可有效改善濃煙擴散到對向隧道及持續往上游擴散之情形，以增加人員逃生之機會。

關鍵字

計算流體力學(CFD) ； 火災動力學模擬器(FDS) ； 火災 ； 煙流 ； 八卦山隧道

並列摘要

When a big fire takes place inside a long tunnel, lots of smoke is generated due to limited supply of outside air. Owing to tunnel's confinement and difficulty for smoke venting, the generated heavy smoke often becomes the major cause of heavy casualties. Ba-Gua Mountain Tunnel, the second longest tunnel in Taiwan was chosen as the target for this simulation study. The FDS software was used to implement 1:1 full scale fire simulations inside the tunnel. With the smoke simulation results, different operating procedures of the ventilating fans were developed to improve the ventilation thereby control and confine the smoke layer. The impact of different ventilating procedures on the personnel's emergency escape was also evaluated at the same time. This stuy shows that a full scale simulation using the entire tunnel instead of limited tunnel length is necessary in order to provide correct simulation results. When a fire occurs, it will be very helpful to prevent the smoke from entering the opposite lane (tunnel) by switching all the fans on that tunnel into an ”aspiration” mode. By changing the number and the ventilating direction of the axial fans at the central shaft and the jet fans at both ends of the tunnel, one can alleviate spreading smoke into the upper section of the tunnel and entering the opposite lane (tunnel) thus enhance the personnel's opportunity for escaping.

並列關鍵字

computational fluid dynamics (CFD) ； Fire Dynamics Simulator (FDS) ； fire ； smoke ； Ba-Gua Mountain Tunnel