Fluid Mechanics Aspects of Fire and Smoke Dynamics in Enclosures

Content: Introduction  The candle flame  The importance of chemistry, heat transfer and fluid mechanics in fires  Chemistry  Heat transfer  Fluid mechanics and turbulence  Combustion and fire  Fire modelling   Turbulent flows with chemical reaction  Fluid properties - state properties - mixtures  Fluid properties  Mass density  Viscosity  Specific heat  Conduction coefficient  Diffusion coefficient  State properties  Pressure  Temperature  Internal energy  Enthalpy  Entropy  Equation of state  Mixtures  Combustion  Chemical reaction  Thermodynamics  Enthalpy  Temperature  Chemical kinetics  Transport equations  Conservation of mass  Momentum equations  Conservation of energy  Convection  Conduction  Radiation  Transport of species  Mixture fraction  Bernoulli  Hydrostatics  Buoyancy  Non-dimensional numbers  Fluid properties  Flow properties  Scaling laws  Turbulence  Reynolds number  Reynolds averaging  Turbulence modeling  Energy cascade  Turbulent scales  Turbulence modelling  Boundary layer flow  Internal flows - pressure losses  Entrainment  Impinging flow  Evaporation  Pyrolysis   Turbulent flames and fire plumes  Flammability  Flammability limits - threshold temperature  Addition of gases  Flammability of liquid fuels  Premixed flames  Laminar premixed flame structure  Laminar burning velocity  The effect of turbulence  Diffusion flames  Laminar diffusion flame structure  The effect of turbulence  Jet flames  Extinction of flames  Premixed flames  Diffusion flames  Fire plumes  Free fire plumes  Average flame height  Temperature evolution  Kelvin-Helmholtz instability  The effect of wind 1 Transition from buoyancy-driven to momentum-driven jets  Correlations  Interaction with non-combustible walls  Interaction with non-combustible ceiling  The effect of ventilation  Reduced oxygen at ambient temperature  Oxygen-enriched fire plumes  Vitiated conditions  Fire whirls  Flame spread  Flame spread velocity - a heat balance  Opposed flow flame spread over a thermally thick fuel  Opposed flow flame spread over a thermally thin fuel  Concurrent flow flame spread over a thermally thick fuel  Concurrent flow flame spread over a thermally thin fuel  Gas phase phenomena  Horizontal surface  Natural convection  Concurrent airflow  Counter-current airflow  Vertical surface Inclined surface Parallel vertical plates configuration  Corner configuration   Smoke plumes  Introduction Axisymmetric plume  Theory and mathematical modelling  Model development under the Boussinesq approximation  Experiments  Line plume  Description of the configuration  Conservation equations  Experimental studies  Transition from line to axisymmetric plume  Wall and corner interaction with plumes  Detailed example: line plume bounded by an adiabatic wall  General correlations for wall and corner configurations  Interaction of a plume with a ceiling  Description of a ceiling-jet  Alpert\'s Integral model  Simplified correlations  Additional considerations  Smoke layer build-up in a room  Balcony and window spill plumes  Balcony spill plumes  Window plumes  Scaling laws and buoyant releases  Exercises  Analytical solution for the Line plume problem  Design of a reduced-scale helium/air mixture experiment of a car fire in a tunnel   Fire and smoke dynamics in enclosures  Some fundamentals on flows through openings  Growing fire  Fire source  Fuel-controlled growing fire  Ventilation-controlled growing fire  Smoke dynamics  Flows through openings  Horizontal openings  Vertical openings  Natural and mechanical ventilation  Zone modeling  Fully developed fire  Fire source  Smoke dynamics  Flows through openings  Horizontal openings  Vertical openings  Natural and mechanical ventilation  Zone modeling  Pulsating fire  Backdraft  Fires in well-confined enclosures   Driving forces in smoke and heat control  Buoyancy - the stack effect  Natural stack effect  Fire-induced buoyancy  Pressurization  Natural ventilation  Mechanical ventilation  Vertical ventilation  Horizontal ventilation  Tunnels  Other underground structures  Smoke extraction  The effect of wind  Positive pressure ventilation  Air curtains  Exercises   Impact of water on fire and smoke dynamics  Individual evaporating water droplet  Heat and mass transfer  Flow equations  Sprays of water droplets  Characterization of sprays  Region near the nozzle  Water flow rate  Droplet size and velocity distribution  Spray cone angle  Spray-induced momentum  Water curtains  Heat absorption by water  Interaction of water with smoke  Sprinkler and water mist sprays  Water curtain  Fire fighting  Interaction of water with flames  Water as fire suppressant   Introduction to fire modelling in computational fluid dynamics  Introduction  Laminar diffusion flames  Instantaneous transport equations  Combustion modelling Infinitely fast chemistry  Finite-rate chemistry  Turbulence modelling  DNS  RANS  LES  Turbulent non-premixed combustion  Infinitely fast chemistry with a presumed PDF  Flame sheet model  Chemical equilibrium model  Steady Laminar Flamelet Modelling (SLFM)  Finite rate chemistry  Eddy Break-Up (EBU) model and Eddy Dissipation Model (EDM)  Eddy Dissipation Concept (EDC)  Conditional Moment Closure (CMC)  Transported PDF models  Radiation modelling  Models for radiative transfer  The P-1 Radiation Model  The Finite Volume Method (FVM)  Models for the absorption coefficient  Turbulence Radiation Interaction (TRI)  The soot problem  Soot nature, morphology and general description of its chemistry  Importance of soot modelling  Sootiness and radiation  Interaction of soot with carbon monoxide  The sootiness of fuels  The laminar smoke point height  The Threshold Sooting Index (TSI)  Soot modelling  Laminar flames  Turbulent flames  Basics of numerical discretization  Discretization schemes  Description of a 1-D example  Explicit scheme  Implicit scheme  Initial and boundary conditions  Properties of numerical methods  Consistency  Stability  Convergence  Conservativeness  Boundedness  Pressure-velocity coupling  The importance of the computational mesh  Boundary conditions  Fire source  Gaseous fuel  Liquid fuel  Solid fuel  Turbulence inflow boundary conditions  Walls  Velocity  Temperature  Open boundary conditions (natural ventilation)  Velocity and scalars  Pressure  Mechanical ventilation and pressure effects  Fixed velocity  Fan curves and pressure effects  Examples of cfd simulations  Non-reacting buoyant plume Test case description  Simulation set-up  Results  Hot air plume impinging on a horizontal plate  Test case description  Simulation set-up  Results  Free-burning turbulent buoyant flame  Test case description  Simulation set-up  Results  Over-ventilated enclosure fire  Test case description  Simulation set-up and Results  Interaction of a hot air plume with a water spray  Test case description  Simulation set-up  Results  Underventilated enclosure fire with mechanical ventilation  Test case description  Simulation set-up  Results  Fire spread modelling     References  Subject Index