there are two types of heat transfer happening in this example. The first one is convection. As air is heated, it expands. As it expands, it becomes lighter than the surrounding air and it rises. It becomes ash. The second type of heat transfer happening is radiation. It is the type of heat one feels when sitting in front of a fireplace or around a campfire, As it is in this example. Hope I helped!
It sounds fine, but it may be a bit too long. It's difficult to shorten things like this, but getting more straight to the point would give it that "catchy" feel.
