Page 89 - Abstract book - TJSSF-2020

Thailand – Japan Student Science Fair 2020 (TJ-SSF 2020)
“Seeding Innovations through Fostering Thailand – Japan Youth Friendship”

Paraffin vapor flames combust independently at a constant distance caused
by the speed of falling vapor and the local oxygen environment

Kouyou Fu
1
Advisor: Nobuzumi Iwakawa
1

Bunkyo Gakuin University Girls’ High School
1

Abstract

Paraffin is a complex hydrocarbon that is commonly used in candles. Paraffin vapor is known to
combust spontaneously, and I found that it burns twice during the phenomenon, I wanted to find the
reason of the twice combustion. The objective of our research is to better understand the mechanism of
this spontaneous combustion. As a result, we found that the vapor combustion occurs in two stages, and
two flames are produced in quick succession. The distance between the maximum height of the first
flame and the starting point of the second flame was fairly constant. Then we repeated the trial while
suppressing each of the two flames in turn to determine if there was a dependent relationship between
them. We can conclude that the probable reason for the “constant distance between the two flames” is
that the speed of the falling paraffin vapor is constant so that each trial produced similar results. And
we found that the two flame is independence so I consider that the two combustion ignites with different
oxygen and the reason of the two combustion is that the paraffin vapor separate during the dropping,
part of them burn at first, then the other burns the second time.

Keywords: paraffin, vapor, spontaneous, combustion, independence, ignite, separate

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