三维单室火灾温度及速度场的数值模拟

利用 FL UENT CFD软件平台对单室火灾中烟气流动、传热及燃烧过程进行数值模拟 ,计算结果与实验数据吻合较好。     

从事故成因谈大型石油库区火灾预防

对近年来国内外原油罐区一些典型火灾进行了案例研究,分析了导致罐区火灾发生的各种因素,从“以防为主,防消结合”的消防思想出发,对石油储罐区火灾预防管理策略进行了探讨.     

大型超市火灾危险性及消防安全对策探析

本文主要对我国的大型尝试在目前阶段的消防安全现状进行了详细地论述,并且全面地分析了我国当前大型超市的布局特点以及超市火灾的危险性,重点探究了大型超市火灾的预防对策以及大型超市火灾的扑救对策。     

大型超市火灾危险性及消防安全对策探析

本文主要对我国的大型尝试在目前阶段的消防安全现状进行了详细地论述,并且全面地分析了我国当前大型超市的布局特点以及超市火灾的危险性,重点探究了大型超市火灾的预防对策以及大型超市火灾的扑救对策。     

Findings of the International Road Tunnel Fire Detection Research Project

Fire detection systems are essential fire protection elements for road tunnels to detect fires, activate safety systems and direct evacuation and firefighting. However, information on the performance of these systems is limited and guidelines for application of tunnel fire detection systems are not fully developed. The National Research Council of Canada and the Fire Protection Research Foundation, with support of government organizations, industries and private sector organizations, have completed a research project to investigate current fire detection technologies for road tunnel protection. The project included studies on the detection performance of current fire detection technologies with both laboratory and field fire tests combined with computer modelling studies. This paper provides an overview of the findings of the project. Fire detectors, fire scenarios and test protocols used in the test program are described. A summary of the research results of the series of full-scale fire tests conducted in a laboratory tunnel facility and in an operating road tunnel as well as of the computer modelling activities will be reported.     

Fire Safety Engineering Research and Technology Centre (FireSERT) University of Ulster: Recent Developments

The Institute of Fire Safety Engineering Research and Technology Centre (FireSERT) at the University of Ulster in Northern Ireland has been a major provider of higher technical fire safety education, fire related research and services to industry for over 20 years. Its internationally recognised research spans the fields of fire dynamics, structural fire engineering, human behaviour in fire and more recently fire (CFD) modelling. Since 1991, it has offered the only PG Dip/MSc Fire Safety Engineering programme in the United Kingdom. In September 2000 FireSERT was the recipient of a £5.7 m Joint Infrastructure Fund (JIF) Award to build new fire safety engineering laboratories on the University's Jordanstown campus. These new facilities unparallel in the University sector in the UK offer greater scope and depth to the FireSERT's research portfolios. The new facilities will be extensively used in support of FireSERT's suite of MSc Fire Safety Engineering and DPhil programmes. This paper presents a brief history of FireSERT and its achievements, together with an update on the new facility, current research themes, taught programmes, research opportunities and visions for the future.     

Predicting airflow distribution and contaminant transport in aircraft cabins with a simplified gasper model

This study investigated the air distribution and contaminant transport in aircraft cabins with gaspers by using computational fluid dynamics (CFD). If the detailed gasper geometry were used in the CFD simulations, the grid number would be unacceptably high. To reduce the grid number, this investigation proposed a method for simplifying the gasper geometry. The method was then validated by two sets of experimental data obtained from a cabin mockup and a real aircraft cabin. It was found that for the cabin mockup, the CFD simulation with the simplified gasper model reduced the grid number from 1.58 to 0.3 million and the computing cost from 2 days to 1 hour without compromising the accuracy. In the five-row economy-class cabin of the MD-82 airplane, the CFD simulation with the simplified gasper model was acceptable in predicting the distribution of air velocity, air temperature, and contaminant concentration.     

天然气管道火灾危险区域预测方法与预防措施

论述了城市埋地天然气管道泄漏事故的原因和后果。建立了火灾危险区域计算关系式,结合北京市近年来典型的管道事故,对事故后果的主要影响因素（管道运行压力、管道破损面积等）进行了定量分析。火灾危险区域半径大于城镇燃气设计规范中规定的管道距建筑物的最小距离,管道运营公司应当加强与公众及第三方施工单位的联系,降低管道泄漏及火灾风险。     

Computational Fluid Dynamics and the Design of Sewage Storage Chambers

Recently in the UK, there has been significant interest in the design of combined sewer overflow chambers and storage tanks. This paper describes an extensive laboratory and computational fluid dynamics study into the hydraulic performance and sediment retention efficiency of tanks. The work has shown that (i) it is possible to predict the flow field which is measured in the laboratory using computational fluid dynamics, and (ii) a critical bed shear stress may be used to determine the extent of sediment deposition. Subsequently a bed shear stress model and the particle tracking routine in 'FLUENT'have been used to compare the sediment retention efficiency of eight different chamber designs. The results showed that the length to breadth ratio of the chamber was the most important parameter to influence sediment deposition, and that changes to the benching and longitudinal gradient of the tank had minimal effect.     

Socioeconomic Characteristics and Their Relationship to Fire Incidence: A Review of the Literature

This article presents a literature review of the socioeconomic modeling of fire incidence, with an emphasis on urban residential fires. The development and history of socioeconomic models of fire incidence are reviewed from the perspectives of ecology and location economics within the urban planning discipline, which encompasses sociological, economic, epidemiological, and interdisciplinary approaches. The predominant methodology used is a thematic type of qualitative analysis, and detailed information on variables selected and results are offered where appropriate. The article closes with suggestions for further research.     

Coupled simulation of heat and moisture transport in air and porous materials for the assessment of moisture related damage

This paper describes the coupling of a model for heat and moisture transport in porous materials to a commercial Computational Fluid Dynamics (CFD) package. The combination of CFD and the material model makes it possible to assess the risk of moisture related damage in valuable objects for cases with large temperature or humidity gradients in the air. To couple both models the choice was made to integrate the porous material model into the CFD package. This requires the heat and moisture transport equations in the air and the porous material to be written down in function of the same transported variables. Validation with benchmark experiments proved the good functionality of the coupled model. A simulation study of a microclimate vitrine for paintings shows that phenomena observed in these vitrines are well predicted by the model and that data generated by the model provides additional insights in the physical mechanisms behind these phenomena.     

Airborne spread of expiratory droplet nuclei between the occupants of indoor environments: A review

This article reviews past studies of airborne transmission between occupants in indoor environments, focusing on the spread of expiratory droplet nuclei from mouth/nose to mouth/nose for non‐specific diseases. Special attention is paid to summarizing what is known about the influential factors, the inappropriate simplifications of the thermofluid boundary conditions of thermal manikins, the challenges facing the available experimental techniques, and the limitations of available evaluation methods. Secondary issues are highlighted, and some new ways to improve our understanding of airborne transmission indoors are provided. The characteristics of airborne spread of expiratory droplet nuclei between occupants, which are influenced correlatively by both environmental and personal factors, were widely revealed under steady‐state conditions. Owing to the different boundary conditions used, some inconsistent findings on specific influential factors have been published. The available instrumentation was too slow to provide accurate concentration profiles for time‐dependent evaluations of events with obvious time characteristics, while computational fluid dynamics (CFD) studies were mainly performed in the framework of inherently steady Reynolds‐averaged Navier‐Stokes modeling. Future research needs in 3 areas are identified: the importance of the direction of indoor airflow patterns, the dynamics of airborne transmission, and the application of CFD simulations.     

One-dimensional modelling of the secondary clarifier-factors affecting simulation in the clarification zone and the assessment of the thickening flow dependence

This paper presents a one-dimensional (1-D) model of the secondary settling tank (SST), and the drive for model development is discussed using steady-state simulation results generated with a 2-D computational fluid dynamics (CFD) model. Concentration profiles measured in a flat-bottom circular (fbSST) that is equipped with suction-lift sludge removal, served for CFD model validation. We investigate the factors that may deteriorate the 1-D simulation performance of clarifier models, which incorporate dispersion both in terms of the effluent sludge concentration and in terms of the sludge blanket height. Furthermore, dispersion-models can account for the effect of clarifier flow conditions on thickening performance. However, correlations, found in the literature, are shown to have limited efficiency under the wide flow boundary conditions examined in this study. Optimisation of the 1-D clarifier model structure is proposed by using an overflow dependent dispersion coefficient and including a feed flow dependent reduction factor in the downward convective velocity term. Results obtained show improved simulation performance in the clarification zone and allow for an efficient flow-dependency formulation of the thickening performance.     

Methodologies for hazard analysis and risk assessment in the petroleum refining and storage industry — Part II

The report briefly describes the consecutive steps in the identification, assessment and comparison of hazards and associated risk. These techniques can be helpful in setting the priorities for the decision on measures to reduce risk. When quantifying risk for the comparison of alternative cases, the use of a consistent data base is stressed. It is pointed out that the risk assessment techniques described in the report, although potentially valuable tools for improving overall safety performance, have short-comings particularly in dealing with human factors. A glossary is appended to define terms as they are used in this report and a list of recommended further reading is included. Part I appeared inFire Technology, August 1984. Prepared by the Ad-Hoc Risk Assessment Group of the Oil Companies' International Study Group for Conservation of Clean Air and Water in Europe (CONCAWE) Reference: CONCAWE's Ad-Hoc Risk Assessment Group; “Methodologies for Hazard Analysis and Risk Assessment in the Petroleum Refining and Storage Industry, Part II,” Fire Technology, Vol. 20, No. 4, November 1984, p. 43     

Methodologies for hazard analysis and risk assessment in the petroleum refining and storage industry — Part I

The report briefly describes the consecutive steps in the identification, assessment and comparison of hazards and associated risk. These techniques can be helpful in setting the priorities for the decision on measures to reduce risk. When quantifying risk for the comparison of alternative cases, the use of a consistent data base is stressed. It is pointed out that the risk assessment techniques described in the report, although potentially valuable tools for improving overall safety performance, have shortcomings particularly in dealing with human factors. A glossary is appended to define terms as they are used in this report and a list of recommended further reading is included. Part II will appear inFire Technology, November 1984. Reference: CONCAWE's Ad-Hoc Risk Assessment Group; “Methodologies for Hazard Analysis and Risk Assessment in the Petroleum Refining and Storage Industry”, Fire Technology, Vol. 20, No. 3, August 1984, p. 23.     

Predicting transient particle transport in enclosed environments with the combined computational fluid dynamics and Markov chain method

To quickly obtain information about airborne infectious disease transmission in enclosed environments is critical in reducing the infection risk to the occupants. This study developed a combined computational fluid dynamics (CFD) and Markov chain method for quickly predicting transient particle transport in enclosed environments. The method first calculated a transition probability matrix using CFD simulations. Next, the Markov chain technique was applied to calculate the transient particle concentration distributions. This investigation used three cases, particle transport in an isothermal clean room, an office with an underfloor air distribution system, and the first‐class cabin of an MD‐82 airliner, to validate the combined CFD and Markov chain method. The general trends of the particle concentrations vs. time predicted by the Markov chain method agreed with the CFD simulations for these cases. The proposed Markov chain method can provide faster‐than‐real‐time information about particle transport in enclosed environments. Furthermore, for a fixed airflow field, when the source location is changed, the Markov chain method can be used to avoid recalculation of the particle transport equation and thus reduce computing costs.     

Case study: the performance and design outline of a buffering stormwater drainage system for a low-lying area

Performance evaluation and safety assessment of a buffering stormwater drainage system (BSDS) for a low-lying area are discussed in this paper. Unlike a conventional pump drainage system, the BSDS, which drains stormwater runoff of a low-lying area to a nearby channel system through underground conduits with gravity, and then buffering peak flows with the storage capacity of a channel system, will discharge stormwater to rivers outside the low-lying area with pumps or flood gates if necessary. This kind of drainage system is considered to be environment friendly and economic both in terms of capital cost and operating & maintenance expenses. To investigate the design parameters and evaluate the performance and safety of BSDS, a hydraulic model coupling the conduit systems and a channel system was developed in this paper, and a case-study approach based on field investigation and simulation test was used. Moreover, the design requirements for safety of BSDS were drawn through a simulation test.     

Geochemical Landscape Analysis: Development and Application to the Risk Assessment of Acid Mine Drainage. A Case Study in Central Sweden

Acid mine drainage containing toxic contaminants is a major cause of landscape degradation at numerous historic mine sites in Europe. Risk assessment of acid mine drainage and related polluted lands requires an approach that is able to study the complexity of pollution emissions and impacted landscapes. The objective of this paper is to link geochemical contaminant fate modelling and landscape analysis for the risk assessment of acid mine drainage along the source–pathway–receptor chain. A simple geochemical landscape analysis tool is developed using landscape ecology spatial analysis and geochemical modelling methods. A case study is presented for the analysis of geochemical landscapes in central Sweden. Results show that the method can be used efficiently for the risk assessment of toxic mine contaminants in the complex wetland landscape in the study area.