基于CFD的大型储油罐区池火灾数值模拟*

为研究大型储油罐区池火灾温度、热辐射强度、流速、组分等燃烧特性参数在油罐外不同区域的变化规律,以10万m3原油储罐区为研究对象,构建罐区池火灾燃烧数学模型,运用计算流体动力学（Computational Fluid Dynamics,CFD）技术进行数值模拟研究。结果表明:整个火场温度大致呈锥形分布,火焰温度最高可达1 500 K,纵向来看,底部温度较高,上部温度逐渐降低,径向来看,中心温度较高,周围温度逐渐降低;随着距罐壁以及距罐顶距离的不断增加,热辐射强度均呈现逐渐降低的趋势,最高热辐射强度为132 kW/m2;罐顶上方区域存在火焰卷吸现象,中心位置流速最大,最高可达56 m/s,罐底区域存在火焰贴壁现象;得到燃烧产物（CO和CO2）的体积分数分布,以CO体积分数为0.001作为判断依据,推断出火焰高度为120 m。研究结果可为今后此类火灾事故的防治提供理论支撑。     

Seismic risk assessment of liquid overtopping in a steel storage tank equipped with a single deck floating roof

Major earthquakes have demonstrated that Natech events can be triggered by liquid overtopping in liquid storage tanks equipped with floating roofs. Thus, research on the dynamic behaviour of steel storage tanks with floating roofs is still required. In this paper, the seismic risk against liquid overtopping in a real steel storage tank with a floating roof was analysed using a simplified model that was validated by a refined finite element model based on the arbitrary Lagrangian-Eulerian approach. The simplified model utilizes the Lagrangian of a floating roof-fluid system and is capable of providing a response history of the floating roof. It was demonstrated that it could predict the maximum vertical displacement very accurately, while some differences were observed in the response history of vertical displacement. The computational time for a single response history analysis based on the simplified model amounted to a few minutes, which is significantly less demanding compared to hours required for response history analysis in the case of the refined FE model. The simplified model is thus appropriate for the seismic fragility analysis considering the overtopping limit state. It is shown that the fragility curves are significantly affected by the liquid filling level. The risk for liquid overtopping is quite high in the case of a full tank. However, by considering the variation of filling level during the year, the overtopping risk was observed reduced by approximately 30%. Alternatively, the approximate fragility analysis for the liquid overtopping can be performed by utilizing the Eurocode formula for the vertical displacement of liquid. This approach is straightforward, but the formula does not account for the higher mode effects, which may result in overestimated seismic intensity causing overtopping, as discussed in the paper.     

深部采场进路开采顶板稳定性分析与支护设计

为降低深部矿体开采中冒顶事故的发生概率,确保井下安全开采,采用Q系统分级法、RMR岩体分类和BQ分级法对矿区岩体进行质量评价,结合块体理论和三维有限元分析进路开挖后顶板的稳定性。研究表明:部分岩体在进路开挖后顶板处出现较大拉应力集中,抗拉稳定性降低,极有可能出现冒顶事故。针对这类不稳定岩体,提出永久巷道采用锚喷支护,临时巷道采用锚杆穿带支护;并运用悬吊理论、组合梁理论、屈服强度理论和安全系数法分析支护条件下进路顶板的稳定性,优化支护结构参数。通过振弦式锚杆应力计收集现场未支护巷道与支护巷道轴向力,得出该支护设计对开挖后岩体变形起到了明显改善作用。     

音频电透视法在防治矿井水患中的应用

为了探明某矿20910工作面顶板0~100 m上高部区域岩层富水性分布情况,基于音频电透视法,通过在工作面回风巷、运输巷布置了59个发射点,104个接收点,获得了工作面顶板0~50 m、50~100 m高度范围音频电透视成果图。探测结果表明,20910工作面顶板0~100 m存在4处低阻异常区域,实际回采揭露发现涌水点5处,均位于探测低阻异常区域,探测结果与实际揭露结果验证很吻合。实践表明,该矿20910工作面顶板0~100 m音频电透视法探测成果合理可靠,音频电透视法可以准确探测出工作面顶板一定范围内相对富水区域分布情况。     

Evaluating the impact of green roof evapotranspiration on annual building energy performance

The performance of the building envelope predominantly determines the ultimate energy performance throughout the lifecycle of a building. A sustainable alternative to enhance roof performance while limiting heat flux through a roof is integrating passive techniques such as green roof. Particularly, green roof performance is sensitive to local climate. The main objective of this study was to evaluate the evapotranspiration effect of an extensive green roof on annual energy consumption of an office building in relation to the humid continental climate of Republic of Korea. The dynamic behavior of green roof and building energy performance were investigated through a parametric simulation method using green roof module in EnergyPlus coupled with jEPlus. Structural data of the reference building and ASHARE 90.1-2007 operational schedules were used as inputs for baseline building model while inputs for the green roof module were based on experimental data sets. Due to the influence of the humid conditions and local wind current on the evapotranspiration process, it was generally found that high leaf area index (LAI) reduced cooling energy demand and somewhat reduced heating energy demand as well; corresponding to the highest daily evapotranspiration fluxes of 4.79 mm day^?1 in summer and 1.80 mm day^?1 in winter. Increasing LAI from 20% to 100% cover increased evapotranspiration flux by 10.4% in summer and 80.2% in winter. Thus to minimize energy losses in winter, foliage cover must be carefully considered. Within limitations specified, the overall annual building energy consumption deceased by 90.9 GJ (3.7%).     

混凝沉淀-活性炭生物池工艺处理聚苯乙烯废水

可发性聚苯乙烯废水中含有大量表面活性剂(LAS)和其他一些难降解的苯环类物质,总磷高,可生化性差,较难处理,采用中和混凝沉淀-活性炭生物池工艺处理可发性聚苯乙烯(EPS)废水,当进水平均COD_(Cr)为1800mg/L时,出水在80mg/L左右,去除率达95.5%,出水水质稳定,各项水质指标均达到了国家一级排放标准。     

北京绿色屋面节水灌溉技术初探

绿色屋面是城市绿化的重要组成部分。对于象北京这样的缺水城市,绿色屋面的节水灌溉不容忽视。使用节水灌溉技术、优化灌溉水源配置、根据土壤含水率科学确定灌水定额等措施可减少城市绿色屋面的耗水量。     

LPG储罐的失效原因分析

简要介绍了LPG储罐的各种失效形式及其特征,分析了导致储罐失效的主要原因,用事故树分析方法进行整理归纳,并针对各种失效形式分别提出防治措施.     

爆炸与中毒模型在液氨储罐安全评价中的应用

以某公司液氨储罐为例,对液氨储罐区进行危险性分析,选用爆炸与中毒模型对液氨储罐进行安全评价,并提出安全对策措施,为企业制定应急救援预案和政府进行有效的监管提供科学依据.     

厌氧消化-A/O-臭氧催化氧化-BAF工艺处理农药废水生化出水的中试研究

采用“厌氧消化-A/O-臭氧催化氧化-BAF”组合工艺对某农药企业污水处理站生化出水进行中试研究。中试装置设计处理规模为12 t/d,进水水质主要指标： COD为214~346 mg/L,ρ（NH₃-N）为8~35 mg/L,TN为65~108 mg/L。经组合工艺处理后,出水COD为51.2~71.4 mg/L,ρ（NH₃-N）为2.4~6.8 mg/L,TN为13.6~19.2 mg/L,出水水质可达到江苏省《化学工业主要水污染物排放标准》（DB 32/939-2006）中的一级标准。整套工艺对进水具有较强的耐冲击负荷能力,可适应难降解、高氮废水,具有较好的经济效益。