隨著交通路網的發展，隧道的數目於近十年有大量增加。其中雪山隧道使我國累積了建造和營運世界級長隧道的寶貴經驗。衡酌未來環島公路網建設中，尚有更長隧道的建設和營運需求，屆時長隧道在交通運輸上將扮演著比目前更吃重的角色。我國在長隧道建造上已有成熟技術，在營運上的經驗也快速累積中，然而在系統設計和分析上則有待努力。本計畫乃擬憑藉雪山隧道實體通風系統，以及計畫申請人已建構的流場數值模式為基礎，在此主客觀條件已可配合的情況下，提出本計畫，擬仔細探討長隧道通風系統電腦輔助設計分析之要素，以提昇國人相關設計和分析能力。本計畫擬藉雪山隧道和其現有監測系統量取日常營運之通風和交通監測資料，以這些數據檢驗其三維氣流場數理模式。藉此一研究歸納出以三維流場數值模式分析公路長隧道通風系統所需之技術要素，例如:紊流模式、網格型式與密度分布、車流活塞效應之模擬、車流之廢氣與廢熱排放與逸散模擬等。以期建立比一維模式更具理論基礎和可靠度之長隧道通風系統分析工具。一來可以輔助現有系統之平時通風狀況以及火災排煙分析，另外亦可作為設計新隧道通風系統之電腦輔助分析利器。
The development of the national expressway network in Taiwan has added a number of tunnels in the past decade. Among which, Hsuehshan Tunnel is the one that has led this country to acquire the technologies of constructing and operating a rare long road tunnel. In the future, more long tunnels are needed to be constructed in order to complete the entire expressway network. Currently it is necessary for us to prepare not only the tunneling technology and operational procedure but also the knowledge for designing long road tunnel ventilation systems. This project aims to examine the essential ingredients in using CFD to analyze the Hsuehshan Tunnel ventilation system. Based on the Hsuehshan Tunnel and the existing ventilation and traffic-flow measurement systems, the three dimensional numerical flow model of this tunnel will be examined using the in-situ measured data, such as the traffic flow, fan operation, wind speed, air temperature, and pollutant concentrations in each traffic tube or at each monitored location. Essential ingredients that assure proper analysis of the tunnel ventilation flows will be summarized; these ingredients include turbulence models, mesh types and mesh density distributions, piston effect of vehicle fleets, the dispersions of exhaust heat and pollutants, etc. A reliable three-dimensional numerical tool with solid theoretical foundation compared to its one-dimensional counterpart can be developed and can be employed to analyze the ventilation and smoke extraction capabilities of the Hsuehshan Tunnel and other new tunnels to be designed in the future.
