發(fā)布時(shí)間：2018-11-21 09:22

【摘要】：伴隨著人們對交通運(yùn)輸?shù)男枨笕找嬖龃?一大批公路、鐵路隧道不斷地修建起來,豐富了人們的交通方式。隧道在為生活帶來便利的同時(shí),其火災(zāi)隱患更加不容忽視。隧道防滅火一直是國內(nèi)外專家學(xué)者研究的重要課題,在發(fā)生火災(zāi)時(shí),不僅僅需要對隧道內(nèi)的人員的安全疏散進(jìn)行保障,同時(shí)也要對隧道的結(jié)構(gòu)進(jìn)行一定的防火維護(hù),從而保護(hù)隧道結(jié)構(gòu)不被高溫所破壞。常用的隧道防火維護(hù)結(jié)構(gòu)采用的多為石棉板、膨脹珍珠巖以及各類防火涂料。而不同的材料對于隧道火災(zāi)的影響的研究目前相對較少。本文在吸取了前人工作的基礎(chǔ)上,運(yùn)用了自行設(shè)計(jì)、搭建的縮小尺寸隧道火災(zāi)實(shí)驗(yàn)平臺,以汽油池火為研究對象,考察了一系列不同維護(hù)邊界條件、油盆尺寸以及不同縱向通風(fēng)風(fēng)速的實(shí)驗(yàn),研究成果如下：(1)對隧道火災(zāi)火源熱釋放速率而言,由于封閉空間熱反饋效果增強(qiáng),其油盆尺寸越大,火源燃燒的時(shí)間將會越低；縱向通風(fēng)對火源熱釋放速率有一定增強(qiáng)作用,但當(dāng)風(fēng)速較大時(shí),其影響并不明顯。同時(shí),油盆尺寸較大時(shí),較小的風(fēng)速對其火源熱釋放速率影響也較小；(2)小尺寸油盆在不同的邊界條件下的熱釋放速率基本相同,當(dāng)油盆增大后,由于熱反饋效果的增強(qiáng)作用,使熱釋放速率在石棉板邊界條件下有所提升；風(fēng)速作用下的不同邊界條件熱釋放速率基本相同；(3)邊界條件發(fā)生變化對火源正上方溫度場有著一定的影響,在油盆尺寸較小的情況下,石棉板邊界條件的火源豎直方向溫度變化與玻璃邊界條件豎向溫度基本相同,隨著油盆尺寸的增加,不同邊界條件對于火源豎向溫度影響越明顯,兩者溫度的比較可高達(dá)150℃。同時(shí),隨著油盆的增大也會使火源熱釋放速率增大；(4)在前人研究基礎(chǔ)上,本文通過實(shí)驗(yàn)發(fā)現(xiàn)邊界條件溫度的衰減有著一定的影響,故在火災(zāi)沿程溫度衰減公式中應(yīng)考慮到不同邊界條件,即其導(dǎo)熱系數(shù)所帶來的影響。
[Abstract]:With the increasing demand for traffic and transportation, a large number of highways and railway tunnels have been built up, enriching people's modes of transportation. Tunnel brings convenience to life at the same time, its fire hidden danger can not be ignored. The fire prevention and extinguishing of tunnel is always an important subject studied by experts and scholars at home and abroad. In case of fire, it is necessary not only to ensure the safe evacuation of the people in the tunnel, but also to maintain the structure of the tunnel against fire. Thus, the tunnel structure is protected from being damaged by high temperature. The commonly used tunnel fire-proof maintenance structure is mostly stone board, expanded perlite and all kinds of fire-proof coatings. However, there are few studies on the influence of different materials on tunnel fire. In this paper, based on the previous work, a self-designed experimental platform for reducing the size of tunnel fire is used to study the gasoline pool fire, and a series of different maintenance boundary conditions are investigated. The experimental results of oil basin size and different longitudinal ventilation wind speed are as follows: (1) for the heat release rate of fire source of tunnel fire, the larger the size of oil basin is, the lower the combustion time of fire source will be due to the enhancement of heat feedback effect in closed space; Longitudinal ventilation has a certain enhancement effect on the heat release rate of fire source, but when the wind speed is large, the effect is not obvious. At the same time, when the size of the oil basin is larger, the smaller wind speed has little effect on the heat release rate of the fire source. (2) the heat release rate of the small oil basin is basically the same under different boundary conditions. When the oil basin increases, the heat release rate increases under the boundary condition of stone and cotton board because of the enhanced effect of thermal feedback; The heat release rate of different boundary conditions under the action of wind speed is basically the same. (3) the change of boundary conditions has a certain influence on the temperature field over the fire source. When the size of the oil basin is small, the vertical temperature change of the fire source is basically the same as the vertical temperature of the glass boundary condition. With the increase of the oil basin size, the effect of different boundary conditions on the vertical temperature of the fire source is more obvious, and the comparison of the two temperatures can be as high as 150 鈩，

本文編號：2346547