高科技廠房防火安全性能研究-避難安全評估

Abstract

本論文分為兩個方向來探討無塵室內的火災防護。第一，利用NIST發展的FDS來模擬廠房內煙流漫延的情形；第二，利用簡算模型與電腦動態避難程式（Simulex）來討論廠房內人員的避難動線與避難時間。最後歸納第一與第二部分之工作對我國的建築技術規則提出相關的建議修正方向。第一部份的研究結果顯示，無塵室的牆邊與牆角是火災發生時最危險且不易偵測的地方，在本論文中又以位於牆邊（位置‚）之情形最為嚴重。本研究之無塵室內的空調系統（垂直下吹層流氣流）使得火災產生之濃煙不受防煙垂壁的侷限而四處擴散，對人員與財產的保護造成艱鉅的挑戰。第二部分的結論則發現，日本方面的DRES Model確定其廠房尺寸與避難出口後，避難時間的結果固定為125.5秒，煙層下降時間為222.9秒，故DRES驗證的結果為一棟安全之廠房。使用紐西蘭方法的結果則發現，其避難時間的不同主要的差別在於偵測器作動的時間有異所造成之結果，而煙層下降的時間可由第一部份的FDS結果得到（見案例分析）。使用Simulex得知，由於模擬之廠房內部人員密度低且人員間距離大，因此避難時人員幾乎全程皆以全速避難，故得到之結果比日本與紐西蘭的簡算模式時間為短。綜合兩部分的結果，建議我國法規對建築物內的火載量、人員密度、群流速度等藉由評比他國法規再根據我國民情加以規範並給予依據。

The fire safety design of a cleanroom is given and evaluated by this thesis, which can be divided into two parts. One is the simulation of fire growth and smoke movement by using Fire Dynamics Simulator developed by NIST. Then, it is followed by the corresponding assessment of the available evacuation time and routes by using a set of simple calculation models, including DRES, and a dynamic computer model, Simulex. Throughout the complete design procedure, several comments and suggestions are made accordingly as the references for the future possible revision of building or fire codes.The predicted results of part one indicate that the fires originated from the corner or wall are dangerous and not easy to be detected. The most severe one is on the wall. The downward laminar air flow will make the smoke unconfined by smoke curtain. And it can spread out throughout the whole cleanroom to threaten the people and properties there. In the second part, the DRES Model finds that the available evacuation time is 125.5 seconds under the specified building configuration and number of exits, whereas the smoke descending time, endangering people, is 222.9 seconds. Consequently, the cleanroom is safe if a fire occurs. As to the evacuation time evaluated by “Fire Engineering Design Guide” of New Zealand, it is found that the difference between evacuation times is resulted from the adaptation of various detection times. The simulation results of Simulex show that all escapees can reach safe place in time. The predicted evacuation time is shorter than these obtained by the last two simple calculation models, because the personnel can evacuate by full speed due the low population density in cleanroom.Summarize the conclusions drawn from the above two parts, it is suggested that the building code should regulate the fire load, population density and walking speed of crowd movement in the building. And those data should be provided by means of science-based measurements or calculation, rather than just adopted from the other countries without any modification.