Large commercial complex,especially its underground business district,has the characteristics of large building space,complicated pattern,large power load and difficult evacuation.When the fire occurs,the rapid decline of oxygen will lead to the increase of toxic gases,and the safe evacuation of personnel has become the core issue of fire safety design.When the fire occurred in the supermarket area and the catering area in the underground business district,the FDS software was used to simulate and analyze the smoke spread characteristics,and the STEPS software was used to simulate and analyze the evacuation.Fire calculation and simulation results show that in the given 6 different fire scenarios,the personnel can escape from the fire area in a limited period of time,but there is less time for security margin.Guarantee sprinkler system,smoke exhaust system,evacuation staircase and evacuation corridor and other fire fighting facilities to work properly,is to meet the basic requirements of safety evacuation.

Taking a large polypropylene warehouse as an example,the fire protection separation was designed and the fire protection design was judged according to the problem of the warehouse area exceeding the specification.FDS and STEPS were used to simulate the warehouse stage and personnel evacuation.The results show that in the condition of natural ventilation,fire smoke does not threat to personnel,the evacuation of all personnel spent 427.5 s in the warehouse,and the safety margin of time is enough.Under the condition that the existing fire fighting facilities work normally,it can meet the safe evacuation of the personnel.The warehouse can achieve the desired fire Safety performance goals for fire prevention design.

According to the 71 cases of domestic and foreign storage tank fire, it indicated that seal ring fire is the major fire form of floating roof tank. Analyzing from the ignition source, the thunder is the major ignition source of seal ring fire. Based on an oil trans?portation station, two scenes of oil gas leakage of sealing ring were simulated through FLACS software and by comparing the simula?tion result, it can be found that fire dike is the dangerous part in oil gas leakage because oil gas will accumulate at fire dike, and the quicker the wind, the shorter the time of accumulation of oil and gas will be. Measures to monitor the combustible gas at the fire dike can be adopted.

A underground business district of commercial complex was selected as the research object.Through the analysis of the overall simulation of the current design situation,it is understood whether the personnel can safely evacuate after the fire affected each other.According to the existing fire control design,the corresponding simulation parameters were defined and selected.FDS and STEPS software were used to simulate the flue gas and evacuation.The simulation results showed that fire will not cause harm to the personnel and they can safely escape the fire area when each fire fighting facilities can work effectively.Therefore,the integrity and effectiveness of fire fighting facilities are the basic conditions to ensure evacuation safety.

Taking the local reconstruction of a large station as an ex-ample, the main fire problems were analyzed, and performance based fire design was conducted. Under the premise of meeting the architectural function, and by field investigation of the fire load of station shop, and analyzing the data, fire scenes were designed. FDS was used to simulate the smoke movement, while Pathfinder and STEPS were used to simulate the evacuation. Based on the simulation results, the fire risk assessment was conducted, and fire countermeasures were put forward.

According to the characteristics of commercial square such as huge area,complex functions and intensive personnel,the underground and underground two floors of a large commercial square are selected as the object of study.A fire area with excessive fire area and large fire load was selected as the set fire scene.For the set fire scene,FDS and EVACNET4 software are used to simulate fire smoke simulation and pedestrian evacuation.The simulation results show that when the fire occurs,the emergency lighting on the evacuation route,the evacuation channel blocked or the evacuation door locked,there may be casualties.The simulation results also show that under the effective conditions of the designed fire fighting facilities,all the people in the set fire scene can be safely evacuated

Taking a propane tank in a chemical plant in Tianjin as an example,the fire scene of the tank fire in propane storage tank is set up.Smoke and heat radiation then the changing rule of the propane tank of pool fire,a sudden increase in the early fire thermal radiation energy,at about 30s in the maximum heat radiation intensity is about 972kW/m2,rapidly decreased in the strongest radiation,at about 40s,the heat radiation of regional stability,and to 600s,the size of the thermal radiation will be close to 277kW/m2.In the early stage of the fire,the smoke was small and round cake shape.With the increase of the fire,the flame also increased significantly,and then the combustion entered a stable stage.

In order to plan evacuation routes,organize effective evacuation,reduce casualties,provide technical support for fire risk assessment,using FDS+Evac and Pathfinder simulation software to simulate the same fire scenario in garment factory.This can avoid the sidedness by using single simulation software.The differences between the two software was compared.The results showed that the time of evacuating from the floor is about 104 s using FDS+Evac simulation software,and about 95 s using Pathfinder software.People usually choose the closer exit to go out.FDS+Evac considers the proximity principle but does not consider people's reaction time and psychological factors.The individual behavior was analysed in Pathfinder software and agreed with the actual situation.But Pathfinder software could not choose the optimal exit.Pathfinder simulation is closer to the actual situation in fire evacuation simulation of the garment factory.

The smoke flow in a atrium of a large commercial complex,smoke status and evacuation are simulated and analyzed.The smoke flow in atrium fires and its influencing factors are studied.The location of fire and fire load are analyzed,and the parameters of evacuation are determined.It is concluded that the smoke does not harm the personnel in the atrium when the fire occurs in the large commercial complex.Through the smoke simulation and the evacuation calculation,the simulation results show that the personnel can escape from the fire area safely.Ensuring the normal work of the atrium in sprinkler system,exhaust system and other fire facilities,is the basic guarantee of atrium fire safe evacuation requirements.

The IMAX theater of large commercial complex was choosed as the object of study.The public walkway part of the cinema and the nearby area is designed as an independent fire prevention zone.FDS and STEPS software were used to simulate the hall fire and personnel evacuation.The results showed that the flue gas will not spread to the aisle and other public areas in the theater,environmental personnel tolerance limit has not been achieved,people can safely evacuated from the public areas.The time of safe margin is larger,which is beneficial for fire fighting and properties transfer.

以某商场类建筑为例,运用Revit软件和Pathfinder软件结合的方式,通过绘制建筑物BIM模型,仿真模拟人员疏散过程,分析与讨论人员疏散结果.模拟结果表明,整体疏散过程体现了快即是慢现象;分层疏散体现了楼梯间、楼梯回转处等易导致人员拥堵、滞留的区域对疏散时间的影响;合理选择开闭不同楼梯间的疏散方式,能够提高疏散速率.若能够加入监控系统,在事故状态下,将已完成或将要完成疏散的楼梯间,对其他楼层开放,则可以更大程度地提高疏散速率.

比较目前应用较多的泄漏扩散模型的适用性,采用平板模型对丙烷气体连续泄漏进行模拟计算,求得平均风速条件下,泄漏源下风向52.35 m的扩散区域内,丙烷气体将对车间人员产生不同程度的健康危害;静风条件下,泄漏源下风向约11.98m的区域内,丙烷气体达到爆炸浓度下限,若有火源易发生气团爆炸.分析结果可为使用丙烷气体的企业预测丙烷泄漏后对不同范围内的人员造成的危害程度提供参考.

In this paper, a large crude oil reserves library in Tianjin is taken for an example. The fire scene for the tank's whole area is simulated using the fire simulation software FDS, which produces the development of fire and the change of the radiation intensity in case of fire. The result is that the rate in the horizontal direction is larger, up to 5.5 m/s, and the maximum value of thermal radiation is 35 KW/m(2). The calculation and assessment result of firefighting cooling water and foam liquid is that the storage of cooling water cannot satisfy the need of the tank's full-size pool fire, and the fire can be suppressed by the foam fireextinguishing system in 46 min. The volume of CO2, CO, SO2, after the full-size pool fire happened 60 s, is 1.47x10(6) m(3), 2.49x10(4) m(3), and 4.98x10(4) m(3) in accordance with the fire area and the calculated smoke rate given by FDS simulation, which has exceeded the requirements of the relevant national environmental standards. The amount of CO2, CO, SO2 the fire in the whole process is much larger than the above figures, which affects the human health to a certain extent.

利用高斯烟团模型建立地面瞬时泄漏源气体扩散浓度分布模型,运用MATLAB软件对模型进行数值模拟,将结果可视化,分析氨气的泄漏扩散过程,最终求得氨气云团扩散形成的中毒危险区范围和氨气云团消散失去毒害作用需要扩散的时间和距离.经计算,氨气云团扩散60 s后能形成的中毒危险区范围是以x=120m,y=0为圆心,半径为50.7m的圆,氨气云团消散失去毒害作用需要扩散的时间为480 s后,此时氨气云团的中心位于(1 068,0,0).该计算结果可对有毒有害气体泄漏后预测扩散危险区范围提供相关依据.

本文对应用于无人机的视觉导航的跑道检测的方法进行了研究。对视觉导航系统中的图像处理及位置姿态解算进行了分析和研究。基于直线检测进行跑道识别；利用经典Hough变换提取跑道图像特征；采用最小二乘法对检测出的跑道边缘直线进行拟合并得出其在图像坐标系中的直线方程。

A set of four axis aircraft PC monitoring system is designed. To accurately grasp the real—time attitude, position information of the four axis aircraft and to precisely control the four axis aircraft, the monitoring system is developed by the host computer to realize four axis aircraft attitude data acquisi—tion, communication and control functions. The function design of the control system is good and friendly man—machine interface enables the user to accurately grasp the flight information of four axis aircraft flight. So four axis aircraft is controlled more accurately. Experimental verification, the monitoring system is simple and practical, stable performance, high precision, Which makes the anti—interference ability of control system stronger, maintains better robustness and stability.

液氨储罐由于储存物质的危险性极易发生火灾爆炸事故.以某金属加工企业液氨储罐区为例,建立改进层次分析模型,通过事故树建立层次结构模型,将事故树的结构重要度转化为为层次分析中的判断矩阵,结合层次分析中权重排序计算,对储罐火灾爆炸的致灾因素进行了定性识别和定量分析.结果显示,卸料口密封的严密性、冷却系统的有效性、是否穿着钉鞋和管道内壁粗糙程度等事件为主要致灾因素,企业应加强日常管理.通过改进后的模型可为企业日常管理提供理论指导.

应用FLUENT软件对某光纤企业丙烷泄漏后的扩散进行数值模拟,在设置边界条件及计算模型的前提下,探究丙烷扩散规律,得到泄漏后丙烷气体的速度、温度、密度、质量浓度等分布情况.结果显示,泄漏后丙烷气云速度由超声速变至亚声速,最后在距泄漏源较远处近似环境风速;在泄漏口垂直方向上,温度呈规律性变化,风口处变化最为明显,近地面温度变化缓慢,反之亦然;密度在泄漏源处可达1.49 kg/m3,随着扩散逐渐接近空气密度;泄漏后大气中丙烷的含量从开始向周边先增大后减小,垂直方向上近地面丙烷含量较其他区更高.此结果可为该种易燃易爆气体的污染监控提供一定的理论依据.

以某光纤企业汇流排丙烷气体瞬时泄漏为例,对重气云扩散模式及其影响因素进行研究,选用盒子模型进行扩散模拟,求得浓度随扩散时间、泄漏点距离的变化规律、产生健康危害的下风向距离以及造成的危害区范围.经计算可知,距泄漏点下风向33.11 m即可达到爆炸浓度下限,丙烷云团瞬时泄露扩散45 s后能造成409.23 m的人员健康危害区.经过分析,企业汇流排实际布局不能满足气体泄漏事故发生时的安全要求.此结果可为发生事故时作业人员确定事故毒害危险区及疏散范围提供合理性依据.

Under certain conditions,liquefied petroleum gas(LPG) is prone to boiling liquid expanding vapor explosion accident.Based on the analysis and identification in the hazard process of the actual case of LPG storage and distribution station handling technology,the basic events which could lead to boiling liquid expanding vapor explosion accident from the fault tree analysis was gived,and the boiling liquid expanding vapor explosion accident tree of LPG and it's dual success tree were constructed.Through the analysis of the minimum cut set of the accident tree and the path set of the dual success tree,the accidents mode and the accidents control mode were obtained,respectively.From the analysis of structure importance degree of the basic events,structure importance degree of minimal cut set and structure importance degree of the minimal radius set,the most direct and the most in need of controlling factors of LPG boiling liquid expanding vapor explosion accident are "the ignition source and tank affected by high temperature baking".It is necessary to strengthen electrical equipment intrinsically safe,take reasonable and effective fire fighting cooling measures,and keep daily security supervision.