本文關(guān)鍵詞： 坡度隧道 數(shù)值模擬 溫度 能見度　出處：《西南交通大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：隨著我國地鐵隧道事業(yè)的發(fā)展,由于自然環(huán)境、地理因素的限制,隧道不可避免的存在坡度。另外,由于在隧道內(nèi)列車自身發(fā)生火災(zāi)的位置具有不確定性,列車位于隧道內(nèi)的位置也不確定,加之隧道坡度形成的煙囪效應(yīng),使隧道火災(zāi)的救援更加復(fù)雜。本文以烏魯木齊市地鐵1號線為研究對象,運(yùn)用計(jì)算流體力學(xué)、傳熱學(xué)、燃燒學(xué)和隧道通風(fēng)基本理論,確定數(shù)值計(jì)算方程,建立相應(yīng)的隧道火災(zāi)煙氣流動的三維數(shù)值模型,對列車不同部位發(fā)生火災(zāi)及隧道坡度和火災(zāi)規(guī)模對隧道內(nèi)各參數(shù)的影響進(jìn)行分析。通過對無通風(fēng)工況下列車位于隧道中部,列車中部發(fā)生火災(zāi)時坡度隧道進(jìn)行模擬,分析隧道內(nèi)溫度、煙氣分布及能見度的情況,研究結(jié)果表明發(fā)生火災(zāi)時隧道拱頂溫度、人高溫度和人高能見度都不滿足隧道火災(zāi)通風(fēng)標(biāo)準(zhǔn),故隧道內(nèi)發(fā)生火災(zāi)必須進(jìn)行機(jī)械通風(fēng)；進(jìn)而根據(jù)列車不同位置發(fā)生火災(zāi),分析不同通風(fēng)風(fēng)速時隧道內(nèi)縱向煙氣蔓延規(guī)律及溫度分布,得出各著火點(diǎn)下的豎井最小通風(fēng)量和最小隧道通風(fēng)風(fēng)速,以及此工況下隧道溫度、煙氣及能見度的分布情況。由于列車頭部發(fā)生火災(zāi)時需額外克服坡度造成的影響,故發(fā)現(xiàn)列車頭部發(fā)生火災(zāi)時所需通風(fēng)風(fēng)速最大。對于列車中部和尾部發(fā)生火災(zāi)的情況,由于中部時列車的阻塞使流過列車所在隧道區(qū)域的通風(fēng)風(fēng)速增加,同時火源由于隧道阻塞在上升過程中的空氣卷吸量也大大減小,因此火災(zāi)所需通風(fēng)風(fēng)速比列車尾部時發(fā)生火災(zāi)時相應(yīng)減小。對于列車位于隧道低端、中部和高端發(fā)生火災(zāi)的情況,得出不同隧道位置對隧道內(nèi)通風(fēng)風(fēng)速影響不大。通過對不同坡度、不同火災(zāi)規(guī)模的隧道模型進(jìn)行模擬,確定各種工況下的最小隧道通風(fēng)風(fēng)速,并對此情況下隧道內(nèi)的溫度、煙氣分布及能見度進(jìn)行研究,分析坡度及火災(zāi)規(guī)模對隧道火災(zāi)通風(fēng)的影響,得出同一火災(zāi)規(guī)模,在下坡隧道內(nèi),隨著隧道坡度的增大,所需隧道通風(fēng)風(fēng)速逐漸增加,上坡隧道內(nèi)則相反。而且在一定的隧道坡度下,隨著火災(zāi)規(guī)模的增大,所需通風(fēng)風(fēng)速逐漸增大。
[Abstract]:With the development of subway tunnel in China, because of the restriction of natural environment and geographical factors, the slope of tunnel is inevitable. In addition, the location of train fire in tunnel is uncertain. The location of the train in the tunnel is also uncertain and the chimney effect caused by the slope of the tunnel makes the rescue of tunnel fire more complicated. This paper takes Urumqi Metro Line 1 as the research object and uses computational fluid dynamics. Heat transfer theory, combustion theory and basic theory of tunnel ventilation are used to determine the numerical equations and to establish the corresponding three-dimensional numerical model of smoke flow in tunnel fire. The effects of fire on different parts of the train and the slope and fire scale of the tunnel on the parameters of the tunnel are analyzed. The train is located in the middle of the tunnel under the condition of no ventilation. In the middle of the train fire, the slope tunnel is simulated to analyze the temperature, smoke distribution and visibility in the tunnel. The results show that the tunnel vault temperature occurs when the fire occurs. Both high temperature and high visibility do not meet the ventilation standard of tunnel fire, so mechanical ventilation must be carried out in tunnel fire. Then according to the different locations of the train fire, the longitudinal smoke spread law and temperature distribution in the tunnel with different ventilation wind speed are analyzed, and the minimum ventilation volume and the minimum tunnel ventilation velocity of the shaft under each ignition point are obtained. And the distribution of tunnel temperature, smoke and visibility under this condition. It is found that the ventilation wind speed is the largest when the train fire occurs at the head of the train. For the fire in the middle and rear of the train, the ventilation wind speed in the tunnel area where the train flows increases due to the congestion of the train in the middle part of the train. At the same time, the amount of air entrainment in the rising process of the fire source is also greatly reduced because of the tunnel obstruction, so the ventilation wind speed required by the fire is smaller than that at the rear of the train when the fire occurs. The train is located at the low end of the tunnel. It is concluded that different tunnel locations have little effect on the ventilation wind speed in the middle and high end of the tunnel. The tunnel models with different slope and fire scale are simulated. The minimum wind speed of tunnel ventilation is determined under various working conditions, and the influence of slope and fire scale on tunnel fire ventilation is analyzed by studying the temperature, smoke distribution and visibility in the tunnel. Get the same fire scale, in the downhill tunnel, with the increase of tunnel slope, the required tunnel ventilation wind speed increases gradually, the slope tunnel is opposite, and in a certain slope, with the increase of fire scale. The required ventilation wind speed gradually increases.
【學(xué)位授予單位】：西南交通大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：U453.5;U231.96

【引證文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 鄧人n，

本文編號：1446664