Answer
Dear Eline
That has to do with the temperature. If you see yellow and orange flames, it means that the fire is not as hot as where you see blue flames. For example, in a gas fire, the inside is warmer (blue) than the outside of the flame (yellow).
The same goes for a wood fire: the inside of the fire is warmer than the outside. The type of wood also plays a role here: pine burns up quickly and does not give as much heat (more yellow flames) than, for example, beech wood (more blue flames can be seen than with pine).
There you go, now you have something to say at the next campfire.
Answered by
ir. Bart De Schouwer
For my position I am the manager of a group of engineers who maintain production equipment. It is mainly with my ready knowledge (education, interests, …) that I could answer questions.
Kapeldreef 75 3001 Leuven
http://www.imec-int.com
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