It is a common observation that the temperature for same distance above a candle is more than the temperature at the side of the flame. Why does it happen?

As far as I could think, at the top of a candle heat is transferred both by convection and radiation, while on the sides of the flame radiation is the only mean of heat transfer. Am I correct?

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    $\begingroup$ That would be my guess, too. For example, if you consider a gas cooktop's burners rather than a single candle, there is a considerable amount of heat in the rising hot air above the burners. Even with the burners on their low setting it is impossible to keep my hand above the flames for any length of time, but to the sides of the burners much less heat is felt. $\endgroup$ – Samuel Weir Jan 9 '16 at 5:56
  • $\begingroup$ @SamuelWeir but can we say that there will be no convection sideways to the candle? $\endgroup$ – Abdullah Jan 9 '16 at 8:37
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    $\begingroup$ @Abdullah: The direction of convection is largely determined by the direction of gravity. In a spaceship there is little convection and only diffusion brings oxygen to the site of combustion. $\endgroup$ – RedGrittyBrick Jan 9 '16 at 15:02

,air starts rising upwards as soon as gets heated from bottom of flame And its place is taken by cold air instantly so a current is set up as in convection.top of flame has warm flowing air and radiations while sides only have heat radiation.


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