Methodology for Optimal Fire Evacuations in Underground Mines Based on Simulated Scenarios

The purpose of this chapter is to develop a methodology that will contribute in locating optimal evacuation routes in case of fire that are based on minimal carbon monoxide (CO) exposure during the evacuation procedures. The proposed methodology is tested using simulated fire scenarios from which CO concentration over time curve is extracted from all available evacuation routes and presented in a weighted form based on the accumulating effect of CO inhalation in the form of fractional effective dose (FED). The safety limits of the FED model on which the optimization process is based are determined using a model for the prediction of carboxyhemoglobin (COHb) levels in human blood. The COHb model is associated with predicted clinical symptoms that are the basis for determining the level of incapacitation at which the mineworkers are incapable of completing their evacuation. Also in the process of improving the fire risk analysis, the proposed methodology enables the development of evacuation plans that are based on the results of modeled fire scenarios combined together with the results of the anticipated hazards generated by CO inhalation. The results presented in this chapter indicate a more precise approach in the process of planning the evacuation system inside the underground mines.

Numerical Study on the Outdoor Wind Effects on Movement Smoke along a Corridor

In this chapter, a numerical investigation is presented in order to highlight the effects of outdoor wind on smoke movements along a corridor in a compartment. For this, the Computational Fluid Dynamics (CFD) code, fire dynamics simulator (FDS), was used to model the reactive flows in interaction with outdoor wind. The wind velocity is taken between 0 and 12.12 m/s, based on the experimental result data come from the work of Li et al. was performed. From numerical data, it was found that smoke stratification state in the corridor depends on Froude number (Fr) and it can be divided into three cases: stable buoyant stratification (Fr < 0.38), unstable buoyant stratification (0.38 ≤ Fr < 0.76), and failed stratification (Fr ≥ 0.76). When Fr ≥ 0.76, smoke stratification is completely disturbed and smoke occupies the entire volume of the compartment, highlighting a risk of toxicity to people. Indeed, it was observed that the velocity of the outdoor wind influences strongly the concentration of O2, CO2, CO, and visibility in the corridor and smoke exhaust. Moreover, for the input data used in the numerical modelling, the global sensitivity analysis demonstrated that the main parameters affecting the smoke temperature near the ceiling are the mass flux of fuel and the activation energy.

Shifting Wildfire Trends and Management Implications for the Wildland Urban Interface in the Twenty-first Century

Anthropogenic climate change is projected to impact a significant proportion of ecosystems throughout the world. These shifts in climate are already impacting a diversity of wildland and urban ecosystems, and they are projected to increase wildfire frequency and severity in many regions. This projected increase is the result of the interaction of altered drought, precipitation, and temperature regimes. Understanding shifts in wildfire regimes is critical for managers at the wildland-urban interface that work to protect structures and human life. This chapter will explore how ongoing and future shifts in climate will drive alterations to natural fire regimes in the United States, with focus on implications for the wildland-urban interface.

Mathematical Modeling and Simulation of Development of the Fires in Confined Spaces

The mathematical models of fire distribution in a confined space–in underground garages and in buildings—are described. Integral and computational fluid mechanics methods are used. The chapter presents the results of a fire simulation using the software Fluent. It uses Reynolds-type turbulence models of the Fire Dynamic Simulation or PyroSim graphical interface with a solution model describing a turbulence. For both cases, the pictures of the spread of fire and smoke over time in an atrium of an administrative building and a five-story building of the TUS were presented.

BLEVE Fireball Effects in a Gas Industry: A Numerical Modeling Applied to the Case of an Algeria Gas Industry

This chapter presents the numerical modeling of the BLEVE (Boiling Liquid Expanding Vapor Explosion) thermal effects. The goal is to highlight the possibility to use numerical data in order to estimate the potential damage that would be caused by the BLEVE, based on quantitative risk analysis (QRA). The numerical modeling is carried out using the computational fluid dynamics (CFD) code Fire Dynamics Simulator (FDS) version 6. The BLEVE is defined as a fireball, and in this work, its source is modeled as a vertical release of hot fuel in a short time. Moreover, the fireball dynamics is based on a single-step combustion using an eddy dissipation concept (EDC) model coupled with the default large eddy simulation (LES) turbulence model. Fireball characteristics (diameter, height, heat flux and lifetime) issued from a large-scale experiment are used to demonstrate the ability of FDS to simulate the various steps of the BLEVE phenomenon from ignition up to total burnout. A comparison between BAM (Bundesanstalt für Materialforschung und –prüfung, Allemagne) experiment data and predictions highlights the ability of FDS to model BLEVE effects. From this, a numerical study of the thermal effects of BLEVE in the largest gas field in Algeria was carried out.

A Case Study on the Fire Safety in Historic Buildings in Slovakia

This chapter deals with the issue of fire safety in historic buildings that undergo functional change, restoration, replacement of construction, facade or installation renovation. It analyzes the current technical state in relation to microclimate and fire safety in historic buildings in Slovakia. It pays attention to the legislative framework for building conservation in the Slovak Republic considering its impact on the reconstruction and restoration of historic buildings. It assesses approaches and methods for fire safety solutions in historic buildings depending on the extent of their modification—intervention in the layout, function and construction. It presents solution procedures and knowledge in terms of application of fire safety requirements in historic buildings using model examples in accordance with the Slovak legislation.