Syllabus academic year 2007/2008
Higher education credits: 12.
Grading scale: TH.
Level: G2
(First level).
Language of instruction: The course might be given in English.
VBR033 overlap following cours/es: VBR032, VBR032 och VBRF05.
Compulsory for: BI2.
Optional for: RH4.
Course coordinator: Daniel Gojkovic, daniel.gojkovic@brand.lth.se, Brandteknik och riskhantering.
Prerequisites: FMA415 Mathematics, Calculus in One Variable.
Recommended prerequisits: MMV016 Thermodynamics and Fluid Mechanics, Basic Course.
The number of participants is limited to 54
Selection criteria: Credits remaining for the degree.
Assessment: The final certificate is based on a written examination (individual work), home assignments (individual work), and laboratory work reports (group work), and requires participation in compulsory seminars.
Parts: 2.
Home page: http://www.brand.lth.se/?id=VBR033.
Aim
The overriding aim of the course is that, after taking the course, the students will understand the various stages that a fire in a building goes through. Furthermore, the course is aimed at providing the students with a knowledge base concerning the different methods and techniques applied in the analysis of a fire sequence, as well as developing their ability to critically examine those methods in terms of practical application. The course is also aimed at increasing the engineering-related ability to construct and analyse models.
Knowledge and understanding
For a passing grade the student must
- be able to explain the effect of the enclosure on a fire sequence.
- be able to explain the range of application of the models and the applicable constraints for fire safety engineering computations.
- be able to characterise the various stages of a fire sequence based on various variables.
Skills and abilities
For a passing grade the student must
- be able to apply various manual computation models and computer models (2-zone models) for calculating various variables in a fire sequence.
- be able to calculate the value of various physical variables associated with a fire sequence.
- be able to analyse and interpret results from fire safety engineering experiments.
- be able to judge the reasonableness of calculated results obtained from various computational models.
- be able to estimate data values for input into computational models where these are lacking in the problem statement.
- be able to design fire safety engineering systems for control and handling of combustion gases.
- be able to evaluate the effect the fire event can have on people occupying the building.
- be able to calculate the time before critical conditions are reached for fires in a building.
- be able to defend, orally and in writing, his/her choice of models and assumptions in the analysis of fire sequences in private and public operations.
- be able to present results from fire safety engineering experiments in a clear and scientific manner.
- be able to search for and apply information concerning fire evolution inside buildings in scientific journals and manuals.
- be able to plan and carry out fire safety engineering experiments.
Judgement and approach
For a passing grade the student must
- demonstrate a capacity to make judgements on the applicability of various computation models to various types of problems.
- demonstrate insight into the responsibilities of a fire engineer in choosing and reporting parameters in such a way that the models are used properly.
Contents
- Qualitative description of a fire sequence. Ignition, flame spreading. Various ways of categorising a fire. The effect of the building on the fire.
- Heat release rate. Mass burning rate and time-dependency of the heat release rate, the order of magnitude of the heat release rate, the strengths and weaknesses of various test methods, growth of alfa-t2, the effect of the enclosure on the heat release rate, extraction of a power curve.
- Fire plumes and flames. Froude number, mean flame height, flame-height correlations, various profiles in a plume, ideal plumes, strong and weak plumes, plume correlations, ceiling jets, special issues to be considered in the design process, quasi-stationary conditions, selecting a plume model.
- Pressure profiles. Background on air-flow in buildings. Bernoulli's equation. Various forms of pressure. Computing pressure, rate and mass air-flow through openings.
- Gas temperatures. Energy balance, rate of heat transfer, correlations for computing gas temperatures. Fully-developed fires, ISO 834, temperature calculation.
- Heat transmission. Conduction, convection, and radiation. Visibility factors, emissivity.
- Smoke filling. Pressure build-up in the fire enclosure. Transient smoke filling models. Stationary models for control of combustion gases. Various fire safety engineering systems for handling and control of combustion gases. Continuity equations. Effect of sprinklers on smoke filling. Correlations.
- Combustion products. Equivalency ratios. Soot production. Visibility, dosage. How soot particles are formed. CO, CO2.
- Computer modelling. Sub-models for zone models. Model constraints. CFD models.
Literature
Karlsson, B., Quintiere, J G: Enclosure Fire Dynamics. CRC Press, 1999. ISBN: 0-8493-1300-7
Parts
Code: 0105.
Name: Fire Dynamics.
Higher education credits: 7,5.
Grading scale: TH.
Assessment: Written examination.
Contents: The course is based on lectures and written exercises.
Code: 0205.
Name: Laboratory Work and Homework.
Higher education credits: 4,5.
Grading scale: UG.
Assessment: Home assignments (individual work), and laboratory work reports (group work), and participation in compulsory seminars is also required.
Contents: This part of the course contains a literature seminar and four home assignments (individual work) and four laboratory work reports (group work).