【摘要】：礦井巷道發(fā)生火災(zāi)后，由于受巷道空間相對(duì)狹窄、封閉以及氧氣供應(yīng)不足等特點(diǎn)的影響，往往會(huì)造成重大人身財(cái)產(chǎn)損失。因此，針對(duì)礦井巷道火災(zāi)，研究火源燃燒特性、火區(qū)阻力以及火源燃燒過程中對(duì)下風(fēng)向巷道的影響，對(duì)于合理評(píng)價(jià)火災(zāi)危險(xiǎn)性、科學(xué)分析火區(qū)條件下通風(fēng)系統(tǒng)可靠性、礦井火災(zāi)救援時(shí)合理控制風(fēng)流方向以及隨時(shí)掌握煙流流經(jīng)巷道溫度和風(fēng)量，均具有重要的理論與現(xiàn)實(shí)意義。 （1）本文通過相似實(shí)驗(yàn)?zāi)Ｐ蛯?shí)驗(yàn)測(cè)定了各測(cè)點(diǎn)的風(fēng)流動(dòng)壓和溫度，火區(qū)前后測(cè)點(diǎn)的靜壓差和下風(fēng)向的煙氣組分；對(duì)基于氧消耗原理的火源熱釋放速率方程，火源下風(fēng)向巷道的溫度場(chǎng)方程以及火區(qū)阻力方程進(jìn)行了深入理論研究并確定了計(jì)算方法；確定了火源燃燒過程中不同時(shí)刻的火源熱釋放速率、火區(qū)阻力以及溫度場(chǎng)分布。 （2）分析了火源燃燒過程不同時(shí)刻的熱釋放速率，得出其變化過程要經(jīng)歷三個(gè)階段，首先是快速發(fā)展階段，該階段火源迅速達(dá)到最大熱釋放速率；其次是穩(wěn)定階段，該階段火源以最大熱釋放速率燃燒，持續(xù)時(shí)間大于發(fā)展階段但小于衰減階段；最后是緩慢衰減階段，該階段火源熱釋放速率隨時(shí)間推移逐漸下降，持續(xù)時(shí)間大約占整個(gè)燃燒過程的2/3；正常通風(fēng)情況下火源最大熱釋放速率和通風(fēng)動(dòng)壓之間存在一次方程關(guān)系，煤和坑木分別為Q_(max)=0.0035H_v+0.0175和Q_(max)=0.0039H_v+0.06。 （3）據(jù)火源熱釋放速率t~2模型理論分析了熱釋放速率計(jì)算結(jié)果，得到了煤和坑木燃燒過程熱釋放速率t~2模型，煤的發(fā)展系數(shù)和衰減系數(shù)分別為12kW/min~2和0.12kW/min~2，坑木分別為12kW/min~2和2.2kW/min~2。對(duì)火源熱釋放速率t~2模型積分運(yùn)算，建立了火源總放熱量方程，總放熱量除以煤的質(zhì)量即為單位質(zhì)量煤的放熱量，計(jì)算得到單位質(zhì)量煤和坑木的放熱量分別為432kJ和1658kJ。 （4）實(shí)驗(yàn)確定了溫度場(chǎng)方程實(shí)驗(yàn)系數(shù)Kc，即在火災(zāi)發(fā)展階段Kc=15～20，在火災(zāi)的穩(wěn)定階段Kc=10～15，在火災(zāi)的衰減階段Kc=20～25。研究了斷面溫度t~2模型理論，建立斷面3溫度變化t~2模型，其發(fā)展系數(shù)和衰減系數(shù)分別為0.251K/min~2和0.0708K/min~2。 （5）對(duì)火區(qū)下風(fēng)向溫度場(chǎng)變化規(guī)律分析表明，在礦井巷道火災(zāi)的發(fā)展和穩(wěn)定階段，下風(fēng)向巷道中風(fēng)流的溫度隨著距火區(qū)距離的增大而呈下降趨勢(shì)。在火災(zāi)的衰減階段，由于火源不穩(wěn)定和新鮮風(fēng)流的流入，下風(fēng)向巷道中有一個(gè)溫度下降最快區(qū)段，，這個(gè)區(qū)段首先從靠近火災(zāi)區(qū)開始，然后逐漸向下風(fēng)向巷道的遠(yuǎn)處移動(dòng)。 （6）對(duì)火源總阻力和火區(qū)阻力變化規(guī)律分析得出，巷道中火源在燃燒過程中，其總阻力由正面阻力、摩擦阻力和火區(qū)阻力構(gòu)成；正面阻力隨著燃燒物體積的減小而逐漸減少，摩擦阻力保持不變；火區(qū)阻力在發(fā)展和穩(wěn)定燃燒階段逐漸增大，在衰減階段開始降低并趨向于零；火區(qū)阻力在風(fēng)流溫度增高到351.6K、巷道風(fēng)量為0.419m3/s時(shí)，達(dá)到最大值71.5Pa。
[Abstract]:After the mine roadway fire, due to the relatively narrow space, closed and lack of oxygen supply and other characteristics, it will often cause significant loss of life and property. Therefore, in view of the mine tunnel fire, the characteristics of fire source combustion, the resistance of fire area and the influence of fire source combustion on the downwind tunnel are studied, and the reliability of ventilation system under fire zone condition is scientifically analyzed for evaluating the fire risk reasonably, and analyzing the reliability of ventilation system under the condition of fire area scientifically. In mine fire rescue, the direction of air flow should be controlled reasonably and the temperature and volume of air flowing through the roadway should be grasped at any time. All of them have important theoretical and practical significance. (1) in this paper, the wind flow pressure and temperature at each measuring point, the static pressure difference between the points before and after the fire and the smoke components of the downwind direction are measured by similar experimental model. The heat release rate equation of fire source based on oxygen consumption principle, the temperature field equation of wind tunnel under fire source and the resistance equation of fire zone are studied theoretically and the calculation method is determined. The heat release rate of fire source at different time, the resistance of fire area and the distribution of temperature field are determined. (2) the heat release rate at different time in the process of fire source combustion is analyzed, and it is found that the heat release rate of fire source combustion process goes through three stages. The first stage is the rapid development stage, the fire source rapidly reaches the maximum heat release rate, the second stage is the stable stage, the fire source burns at the maximum heat release rate, the duration is longer than the development stage, but less than the attenuation stage. Finally, the slow decay stage, in which the heat release rate of the fire source decreases gradually with the passage of time, accounts for about 2 / 3 of the whole combustion process. Under normal ventilation, there is a first order equation between the maximum heat release rate of fire source and the dynamic pressure of ventilation. The coal and pit wood are Q _ (max) _ 0. 0035 HV _ v 0.0175 and Q _ (max) _ (max) _ 0. 0039 Hv / v 0.06 respectively. (3) the calculation results of heat release rate are analyzed according to the fire source heat release rate t ~ 2 model. The thermal release rate t ~ (2) model of coal and pit wood combustion is obtained. The development coefficient and attenuation coefficient of coal are 12kW/min~2 and 0.12 kW / min ~ (-2), and 12kW/min~2 and 2.2 kW / min ~ (2), respectively. Based on the integral calculation of the heat release rate t ~ 2 model of the fire source, the total heat release equation of the fire source is established. The total heat emission is divided by the mass of the coal as the heat release of the coal per unit mass. The heat release of unit mass coal and pit wood is calculated to be 432kJ and 1658kJ respectively. (4) the experimental coefficient of temperature field equation Kc is determined by experiments, that is, in the development stage of the fire, in the stable stage of the fire, and in the attenuation stage of the fire, the experimental coefficient of the temperature field equation is Kc. The theory of section temperature t _ 2 model is studied, and the model of section 3 temperature variation t _ 2 is established. The development coefficient and attenuation coefficient are 0.251K/min~2 and 0.0708K / min ~ (2), respectively. (5) the analysis of the variation law of wind direction temperature field under fire zone shows that, In the development and stabilization stage of mine roadway fire, the temperature of air flow in the downwind roadway decreases with the increase of the distance from the fire area. At the attenuation stage of the fire, due to the unstable source of the fire and the inflow of fresh wind flow, there is a section of the downwind roadway in which the temperature drops fastest, which begins near the fire zone. Then it gradually moves down to the distance of the roadway. (6) the total resistance of the fire source and the resistance of the fire zone are analyzed. It is concluded that the total resistance of the fire source in the roadway is composed of the positive resistance, the friction resistance and the resistance in the fire zone. The positive resistance decreases gradually with the decrease of the volume of the combustion material, and the friction resistance remains unchanged, and the resistance in the fire zone increases gradually in the development and steady combustion stage, then decreases and tends to zero at the attenuation stage. The maximum value of resistance in fire zone is 71.5 Pa. when the air flow temperature increases to 351.6 K and the air volume of roadway is 0.419m3/s.
【學(xué)位授予單位】：內(nèi)蒙古科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2013
【分類號(hào)】：TD752

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 傅培舫;周懷春;;巷道火災(zāi)過程中燃燒速率和釋熱速率的預(yù)測(cè)[J];燃燒科學(xué)與技術(shù);2006年05期

2 程小虎;曾艷華;何川;范磊;;隧道火災(zāi)中火區(qū)阻力的理論研究[J];鐵道學(xué)報(bào);2007年05期

3 于麗;王明年;郭春;;秦嶺特長(zhǎng)公路隧道火災(zāi)溫度場(chǎng)的數(shù)值模擬[J];土木工程學(xué)報(bào);2007年06期

4 常相輝;馮先富;張永文;劉斌;;不同溫度下空氣比熱容比測(cè)量裝置的研究[J];物理實(shí)驗(yàn);2011年04期

5 郭江煒;宋雙林;于s

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