共查询到17条相似文献,搜索用时 109 毫秒
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通过研究扬沸前兆噪声特性及其声发射机理,并与典型环境噪声特性差异作了分 析、比较,提取出一组识别特征物理量,以便在扬沸火灾早期能诊断预报扬沸的发生。 相似文献
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原油储罐扬沸火灾由池火灾发展而成,是一种危害性极大的事故.准确预测扬沸事故发生的时间,是扬沸机理研究中的难题之一.现有扬沸时间计算的通用模型由于没有考虑油品的粘性作用,计算结果误差较大.把扬沸火灾简化为无内热源的非稳态传热问题,在此基础上进行传热分析,进而推导出扬沸事故时间计算模型.设定了6组不同尺寸和不同充装水平的原油储罐池火灾,利用推导模型计算出了相应的扬沸事故发生时间.将计算结果与通用模型计算结果以及实验结果进行对比:该模型的准确性由于通用模型,计算结果与实验值误差较小,较为合理.研究结果对于扬沸火灾事故下消防人员的灭火救援的安全保障具有重要意义. 相似文献
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1983年元月25日,四川某矿在露天剥离峒室大爆破装药过程中发生早爆事故,造成××人死亡、××人受伤,财产损失约××万元。笔者对事故发生过程和原因分析如下,供爆破设计、施工及研究人员借鉴。一、基本情况该爆破工程是由某设计院于1982年完成设计,同年11月通过设计审批的。设计装药量952吨,爆破方量116万米~3。爆区内在海拔2160、2184、2209米布置3层共16条平 相似文献
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原油储罐火灾扬沸形成时间预测模型研究 总被引:2,自引:1,他引:1
扬沸火灾是一种突变性火害现象,其发生能导致巨大的人员伤亡和财产损失,其形成时间预测问题一直备受关注。根据能量守恒定律,把原油层内的热量传递看作无内热源、常物性的非稳态传热问题,建晓热量传递模型,通过预测油层内的温度分布,结合小尺度油罐扬沸火灾实验结果,推导出扬沸形成时间预测模型。并对其可靠性进行了案例验证,结果表明模型准确,误筹较小。实验发现随着罐径的增大,水层厚度对扬沸形成时间的影响逐渐减小。通过预测模型计算得到:扬沸形成时间与初始油层厚度和罐径的比值存在正比例关系。 相似文献
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D. Laboureur L. Aprin A. Osmont J.M. Buchlin P. Rambaud 《Journal of Loss Prevention in the Process Industries》2013,26(6):1380-1389
Boilover is defined as a violent ejection of fuel due to the vaporization of a water sub-layer, resulting in an enormous fire enlargement and formation of fireball and ground fire. This paper focuses on the physical principles behind the thin-layer boilover phenomenon, and on the improvement of the thin-layer boilover modeling. Small scale field and laboratory experiments, with a mixture of diesel and oil, and reservoirs ranging from 0.08 to 0.3 m, have been performed. High-speed visualizations and image processing, in parallel to temperature and mass loss measurements allows to better understand the water boiling, and the consequent flame enlargement. The modeling of the boilover period is done through the calculation of the pre-boilover burnt mass ratio and the boilover intensity based on the mass loss and on the flame enlargement. 相似文献
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Floating roof storage tank boilover 总被引:1,自引:0,他引:1
Ibrahim M. Shaluf Salim A. Abdullah 《Journal of Loss Prevention in the Process Industries》2011,24(1):1-7
Storage tanks are important facilities for the major hazard installations (MHIs) to store large quantity of crude oil. There is several fire types can occur with large diameter open top floating roof storage tanks. Boilover is considered one of the most dangerous fires in large-scale oil tank. The world has witnessed many incidents due to boilover in floating roof storage tank. Boilover problem has been studied in experiments and by models to understand how to control the boilover phenomena. An experimental study has been carried out in Jebel Dhanna (JD) terminal area by Abu Dhabi Company for Onshore Oil Operations (ADCO) with support of Resource Protection International (RPI) consultant. 2.4 m diameter and 4.5 m diameters pans have been used to study the characteristics of the large oil-tank fires (i) to gain more knowledge of the boilover phenomenon of crude oil (ii) verify if the crude oil stored by ADCO would boilover (ii) estimation of rate of hot-zone growth and the period needed from ignition to boilover (iii) estimation of radiant heat and consequences of boilover. This paper presents an overview on the floating roof storage tank boilover. The paper also presents briefly boilover experimental research study carried out by ADCO. 相似文献
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Experimental studies of boilover were conducted in small scale rig at Universiti Teknologi PETRONAS (UTP), Malaysia and Loughborough University, United Kingdom. The study at UTP was aimed to demonstrate the ability of conducting tests at a smaller scale to simulate the boilover phenomenon. At Loughborough University, a novel laboratory scale rig was designed and built in order to obtain visual records of fuels' behaviour in a pool fire. The ultimate objective of these studies is to develop a greater understanding of boilover pertaining to fires involving the contents of storage tanks. Fuel mixtures containing light and heavy components were burnt as to study the feasibility of reproducing hot zone formation and boilover in a smaller scale and a safe environment. Boilover occurred after certain period of burning. It is found that thickness of the hot zone changed with time. It is also found that the time needed to start boilover increased when fuel thickness increased. The visualization of the fuel behaviour during the experiments was obtained to better understand the formation and growth of hot zone, the boiling of water layer and hence the boilover occurrence. Based on the data analysis and the photographs recorded from the experiments, the laboratory scale experimental rig could be used to simulate the hot zone formation mechanism and the boilover event safely and successfully. Such information are important for the understanding towards boilover phenomenon. 相似文献
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Boilover is a phenomenon that both stakeholders and fire-fighters in the petrochemical industry try to avoid. This phenomenon results in an explosion of liquid hydrocarbon materials (e.g., crude oil) due to prolonged oil tank fires. The elevated temperature provides energy to vaporize the water sub-layer, which commonly resides at bottom of storage tanks, leading to tremendous fire enlargement as fuel tends to spill over around the tank. Boilover follows the formation of an isothermal layer called ‘hot zone’, and is typically accompanied by continuing bubble appearance in the hot zone. Previous studies have suggested that bubble generation could be a driving force for boilover, as it accelerates heat mixing. However, the effect of bubble generation on the mechanism of hot zone formation has not yet been systematically studied. This work investigates the effect of bubble formation on hot zone formation by installing a metal mesh in a burning fuel container. The size of the mesh grid and the position of the mesh are varied to generate bubbles with different volumes from different depths from the fuel surface. Experimental results demonstrate that the metal mesh definitely increases the volume of bubbles, and significantly reduces the time to form a hot zone. The mesh with small grids generates more bubbles than that with large grids. Additionally, bubbles start to generate earlier when the mesh is fixed nearer the fuel surface. Experimental results provide direct evidence of the bubble effect on hot zone formation. 相似文献
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油罐扬沸火灾防治模拟实验研究 总被引:2,自引:1,他引:1
分析扬沸火灾形成的3个基本物理条件,给出扬沸三角形的概念,提出通过破坏3个基本条件中任一条件来抑制扬沸火灾发生的构想。为解决其防治问题建立小尺度油罐扬沸火灾防治模拟实验台,用沸石和双列盘管式冷却法对扬沸火灾防治进行了实验研究;通过对比两种方法施加前后的油层、油水界面、水层温度和火焰辐射,发现双列盘管式冷却法和沸石能有效地抑制扬沸的形成和降低扬沸的危害程度。从机理上分析,小尺度油罐扬沸火灾的防治方法可为扬沸火灾的防治提供一定的理论依据。 相似文献