Types of combustion Flashcards
1
Q
what is smouldering combustion?
A
- no flame
- hot materials on surface
- oxidation still occurs
2
Q
what is pyrolysis
A
the decomposition of molecules via heat, where oxygen is not required
initiates radical chain reactions
3
Q
fuel lean vs fuel rich
A
fuel lean = too much oxygen
fuel rich = too much fuel
need to find the middle ground = ‘combustion zone’
4
Q
limiting factors to a fire
A
- heat - first to go as it is quickly lost to the surroundings
- oxygen - oxygen gets depleted, reduced to a smoulder
- fuel - keeps burning until entire structure is destroyed
5
Q
what is flaming combustion
A
a substrate burns releasing volatile gases that act as fuel to the flame
6
Q
laminar flame
A
a small flame (eg candle) that has well defined zones and smooth air flow
7
Q
flame colours
A
dull red = 500 - 800
bright red = 800 - 1000
orange = 1000 - 1200
yellow = 1200 - 1400
white = 1400 - 1600
