Learning objectives
Aim of the course is to provide theoretical and applicative knowledge on
physics applied to fire safety engineering. Part of the course is devoted to
numerical analysis applied to heat transfer and fluid flow problems in fire
modeling.
Prerequisites
Basic knowledge of Applied Physics
Course unit content
Fire science and combustion. The combustion process. Theoretical air for
combustion. Combustion by-products and energy release. Oxygen
required for combustion. Tempertaures of flames. Adiabatic flame
temperature.
Limits of Flammability and premixed flames. Measurement of
flammability limits. Flammability diagrams. The structure of a premixed
flame. Heat losses froma a premixed flame. Measurement of burning
velocity. Diffusion flames and fire plumes. Laminar and turbulent jet
flames. Flames from natural fires: the buoyant plume, the fire plume.
Ignition. Ingnition of flammable vapour/air mixtures. Ignition of liquids.
Pilot ignition of solids. Spontaneous ignition. Extinction of flame.
Spread of flame. Flame spread over liquids and solids.
The pre-flashover and post-flashover in compartment fire. The growth
period and the definition of flashover. Regimes of burning. Fire resistance
of buildings.
The productuion and movement of smoke. Rate of smoke production in
fires.
Fire modeling. Two zone and field models. C-Fast amd FDS codes.
Practical applications.
Full programme
Introduction:
Regulatory and engineering approach to fire design:
national and international regulatory framework of reference, the DM May 9, 2007, ISO / TR 13387, stages of fire growth, the condition of flashover, the fire load and specific design fire load.
Thermodynamics of combustion:
combustion process, combustion byproducts, amount of oxygen consumed, theoretical air of combustion, stoichiometric concentration, ventilation ratio, over ventilated and underventilated conditions.
Energy balance of the flame: enthalpy of combustion, adiabatic combustion temperature, minimum energy energy, extinguishing agents, Halons.
Classification of the flames: the limits of flammability and premixed flames, measurement of flammability limits, flammability diagrams, diffusive flames, laminar and turbulent jet flames.
Regimes of burning: RHR, rate of burning, the pool fire, the alpha t-squared model, fire development.
Natural fire: the flame height, the plume of smoke and fire, the ideal model of the plume, the Zukoski model, the Heskestad model, the Thomas model The model of The, the McCaffrey model The model of The , Production and dynamics of the smoke produced by the fire,
Fire resistance of structures: the nominal fire curves, application examples, passive protection of structures.
Numerical analysis applied to the thermo fluid dynamics of the fire: The zone models and field models, C-Fast, FDS.
The exercise activities carried out in the computer lab, focused on case studies, are aimed at the acquisition of the fundamental elements for the use of CFD codes for fire simulation and fire safety design.
Bibliography
INGEGNERIA DELLA SICUREZZA ANTINCENDIO, Antonio La Malfa
Casa Editrice "Lagislazione Tecnica Editrice" di Roma
An Introduction to Fire Dynamics, by D. Drysdale, John Wiley Edition
Teaching methods
The course develops through theory and practice lessons.Part of the course is devoted to
laboratory lessons focused on the use of CFD tools applied to fire
modeling.
Assessment methods and criteria
Practical and oral examimation.
Other information
Lecture attendance is highly recommended.
