CH 7: Heat Release Flashcards
The rate at which the heat energy is generated by burning is termed:
heat release rate
The variables considered when determining a fuel’s heat release rate include all of the following EXCEPT:
ignition temperature
The ________ of a material refers to the amount of energy emitted per unit of fuel mass consumed, and it varies by fuel.
heat of combustion
The ________ is the loss of mass over time from the fuel’s surface when undergoing combustion.
mass burning flux
The ________, often referred to as the burning rate, is the rate at which the fuel is losing mass while undergoing combustion and is usually expressed in kilograms per second (kg/s) or grams per second (g/s).
mass loss rate
________ is used to describe the amount of energy that is required to produce a unit mass of flammable vapor from a combustible that is initially at ambient temperatures.
Heat of gasification
The four ideal fire growth curves include all of the following EXCEPT:
Infinite
Heat release rates of pool fires are dependent on which of the following?
A. Surface area exposed to air
B. Heat of combustion of the fuel
What is the formula to calculate the heat release rate (HRR) of a pool fire?
Q = AF ΔHc
What is the formula to calculate an average flame height?
Hf = 42D
What is the formula to calculate the mass loss flux of a fire?
m = Qflame-Qloss/Lg
What formula could be used to estimate the HRR of upholstered furniture during the growth phase?
Q = 210[fabric factor][padding factor][mass factor][frame factor][style factor]
What is the formula to determine heat release rate of a tiered rack storage fire?
Q = Nt^3
Which of the following is idealized parabolic equation that is approximately proportional to time squared (t2)?
Q = α (t - to)^2
What is the asymptotic mass loss rate for kerosene?
0.039 kg/(m2 - s)
