FV3001 Assignment Brief (2024 - 2025)
The workshall be typed or word-processed in your own words. The deadline for submission is 11:59 p.m. (HKT) on 2nd December 2024.
Learning Outcomes
This piece of assessment will test student’s ability to meet learning outcomes as described hereunder: -
1. Apply the relevant principles and techniques of chemistry, physics, maths to the study of enclosure fire dynamics; (Learning Outcome 1)
2. Critically review and quantify the impact of fire on people / the human body; (Learning Outcome 2) and
3. Critically review the principles of modelling. (Learning Outcome 3)
Assignment Details
Students are required to answer all questions. The assignment will carry 40% weighting of the total mark for this module. Question 1 to Question 5 is designed by Ir Dr William Yan. Question 6 to Question 9 is designed by Mr Evan Wong.
Submission Details
(1) The deadline for submission is 11:59 p.m. (HKT) on 2nd December 2024. Late submission will be dealt with strictly in accordance with UCLan Regulations.
(2) No hard copy is required to be submitted to the SCOPE counter. This assignment should be submitted through Turnitin to CityU SCOPE CANVAS assignment submission folder.
(3) In-text citations and referenced publications shall be added to the answer to each question.
(4) Using AI-generated text to complete your assignment is prohibited. Citation of Harvard style. shall be used for all quoted references. UCLan regards any use of unfair means in an attempt to enhance performance or to influence the standard of award obtained as a serious academic and/or disciplinary offence.
(5) Submission of written assignment shall be type-written in .pdf or .docx format. The file name of your submission shall follow the format as the example below:
FV3001_CHAN Tai Man_G12345678
(6) Students should do whatever means to make sure the files are duly
submitted via the CANVAS system and check whether the work is successfully uploaded (by downloading the file from CANVAS again). All claims on technical problem without strong evidence for unsuccessful uploading shall not be accepted.
(7) It should be the students’ responsibility to double-check the readability (pdf or docx format) of the submitted files.
(8) Administration team will not remove or replace student’s submitted assignment in CANVAS or help students to upload the soft copy of his/her assignments to CANVAS.
Marking Criteria
The Assignment will be marked according to the marking criteria as appended below.
• Question number and page number are provided
• Answers are clear, logical, structural and coherent
• Analysis is step-by-step justified
• Correct equations (if any) are used
• Abbreviations (if any) are elaborated
• Calculations (if any) are accurate
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Assessment Criteria
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Weight (%)
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Calculation
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40%
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Knowledge
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20%
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Analysis
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20%
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Structure
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20%
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FV3001 Fire Dynamics – Assignment
(Q1) Please explain how the Hong Kong FS Code (Code of Practice for Fire Safety in Building 2011) considers the tenability for the occupants suffering fire in the computational fluid dynamic (CFD) models when fire engineering design approach is adopted. Please also explain how these tenability criteria impact on the human body.
(Q2) A compartment with the following data is subjected to a fire. The compartment located in remote area is designed as office usage. The following information is given:
• Automatic smoke alarm is provided;
• No independent water supplies are provided;
• No firefighting devices are provided;
• The office is made of concrete, ρ=2500kg/m3 ; cp=980J/kgK; k=1.5W/mK;
• There are two ventilation openings on the walls. The dimensions (breadth x height) are 3.6mx 1.5mfor Opening 1 and 7.2mx 1.5m for Opening 2;
• The breadth x length x height of the compartment is 7m x 14m x3m;
• Use Annex E of the Eurocode 1(Part 1-2) to determine the fire load density (MJ/m2) incorporating appropriate factor of safety.
Plot the temperature-time curve of the compartment fire for this office.
(Q3) Discuss and compare the ‘standard temperature-time curve (ISO834)’ and the ‘parametric temperature-time curve (based on EN 1991-1-2)’ . Assume that you are a fire engineer for a design task of structural fire resistant design in a commercial building with several compartments. You are required to consider several fire scenarios in different fire compartments. How do you plan to incorporate both aforementioned fire curves in your work?
(Q4) Assume that you are appointed as a fire engineer to adopt fire engineering design on a museum. There is a glorious exhibition hall with 42m inheight. This exhibition hall is specially designed with complicated configuration and irregular shape. The roof of the exhibition hall consists of steel trusses. They are considered to remove fire protection for the purpose of easy maintenance. Which kinds of numerical models may assist you in your design? Please briefly explain the reasons. (Hints: Smoke spread, occupant evacuation and structural fire resistance are recommended to consider.)
(Q5)
(a) Calculate the heat of combustion (kJ/mol) of methane (CH4) in gaseous state for complete combustion at 298K based on the given data on heat of formation in the following table.
(b) Write down the chemical reaction for incomplete combustion of methane with CO and water as the only products and hence estimate related heat released per mole of ethane (gaseous state) consumed at 298K.
(c) Discuss the errors for estimating possible heat released in real fire cases based on the results calculated in part (a) and (b).
Source: Table 1.1 Glassman, I. and Yetter, R. A., 2008, Figure 4.3,
Combustion 4th Edition, Chapter 4, Section B, Page 6, Academic Press
(Q6) Analyse the effect of the heat transfer coefficient of wall and ceiling materials for compartment fire development based on sketches of Semenov Diagram. Hence, on basis of the Semenov Diagram, discuss the corresponding differences on the heat loss to external environment for same compartment size with same building materials: i) a standalone concrete office and ii) an office unit located at the interior of an air conditioned skyscraper.
(Q7)
(a) Find F1-2 for the configuration of two offset perpendicular squares of area A, as shown in the following diagram.
(b) Consider two rectangular surface perpendicular to each other with a common edge that is 1.6m long. The horizontal surface is 0.8m wide and the vertical surface is 1.2m high. The horizontal surface has an emissivity of 0.75 and is maintained at 400K. The vertical surface is black and is maintained at 550K. The back sides of the surfaces are insulated. The surrounding surfaces are at 290K and can be considered to have an emissivity of 0.85. Determine the rate of radiation heat transfer between the horizontal surface and the surroundings. (Tips: the area projections that complete the surface area A3 of the enclosure)
(Q8) Based on the equation used to calculate upper layer temperature as shown in the following:
where ΔTg is the upper gas temperature rise above ambient, K;
Q is the heat release rate of fire, kW
g is the gravitational acceleration, 9.81 m/s2
cp is the specific heat capacity of air, 1 kJ/(kg K)
ρ∞ is the density of air, 1.18 kg/m3
T∞ is the ambient air temperature, 310 K
Ao is the opening area, m2
Ho is the opening height, m
AT is the totalarea of compartment enclosing surface, m2
hk is the heat transfer coefficient, 0.03 kW/m2K
Calculate the upper-layer temperature of a room 3m x 3m in floor area and 2.4m high with a door opening 2m high and 2m wide. The fire source is a steady 800kW fire.
Hence by the above equation, or otherwise, discuss the effect on fire engineering analysis if the ambient temperature is various in different seasons for identical room geometry and fire source.
(Q9) Calculate the minimum fire size at floor level capable of activating fixed temperature heat detectors (rated at 70°C) in a large exhibition hall having the room height of 10 m high. Assume that the ceiling is flat and that the detectors are spaced at 5m centre to centre. Ambient temperature, T∞ = 20°C and g = 9.81 m/s2. Calculate fire sizes, Q, for each of the following locations:-
(a) the fire is directly above the detector;
(b) at the center of the enclosure;
(c) close to one wall;
(d) in a corner