When anything is hotter than its surroundings (like anything on fire),
that heat is given off in a combination of three ways, Radiation,
Convection, and Conduction. In this situation, CONDUCTION is very
minimal. The fire RADIATES heat isotropically (that means equally in all
directions). And heat in the air used for burning rises and CONVECTIVELY
carries heat away.The proportion of RADIATION to CONVECTION depends on a lot of variables, primarily the temperature of the flames. If you feel like being punished, you can see the equations which describe the physics of all this, but we don't want to subject innocent bystanders to advanced integral calculus, so enter at your own risk!