Is Radiation the Primary Method of Heat Transfer in a Brick Oven?

[zoiberg137]

The question is basically asking what method of heat transfer is MOSTLY responsible for heating a pizza inside of a brick oven.

So from what I understand, the majority of the heat is coming from conduction-through the bricks themselves.

Since the questions states that there is a chimney ABOVE the oven, I figured I could rule out that it is heated at all by convection.

However, isn't some of the heat coming from radiation, even if it is a minimal amount? Also, if the chimney was on the side of the fireplace, instead of the top, then the pizza could potentially be heated by all three methods of heat transfer...Right?


OR...is the primary method of heat transfer radiation? I read on a brick oven webiste that their oven heats by radiation. I don't get how the bricks could be giving off radiation...and not by conduction.

Please help! Thanks!

 

[SteamKing]

If the heat is conducted through the bricks, where is the oven (the hot bit)?

What would happen to the heat from the oven if there were no chimney?

What would happen to the kitchen is the bricks were as hot on the outside as on the inside of the oven?

If there is no convection, then why does the oven need a chimney?

 

[zoiberg137]

Well, from what I understand...

Convection is taking place to some degree, however since there is a chimney directly above then it would have to be very minimal. Now if the chimney was on the side of the oven, then convection would be taking a greater part in heating the pizza...though I still don't think it would be the primary heat source.

The oven needs a chimney so that the smoke can escape. Otherwise it would be a hazard to the cooks health as the room would fill up with smoke.

Hmmm...I'm guessing the bricks on the outside do NOT get as hot as on the inside. But why is this? The heat source is the fire. The bricks are responsible for holding heat, which is why the oven stays hot for long periods of time and the fire does not have to stay lit constantly in order for pizza to cook.

Is it the radiation of the fire that is being conducted into the inner layer of bricks? And so the outside of the oven does not get as hot because the radiation does not reach that far?

The more I think about this the more confusing it gets :(

 

[haruspex]

As I understand it, in a traditional brick oven the fire is completely or pretty much out by the time the pizza is put in. Note that the question asks how the pizza is heated, not the bricks.

 

[zoiberg137]

So...the pizza is heated from the heat that is stored in the bricks...via conduction?

Similar to how the top of a regular stove is still hot 15 minutes after you turned the burner off. The stove top isn't radiating heat...as it is not in itself a heat source. But rather it is transferring heat, via conduction, that it stored from the original heat source, the flame?

Or, how about how the ground still feels warm an hour after the sun sets. It's not radiating heat, as the ground itself is not a heat source. Its not convection, as the ground is not a liquid or a gas. The ground feels warm via conduction of the stored heat that it received via radiation from the sun?

 

[haruspex]

So...the pizza is heated from the heat that is stored in the bricks...via conduction?

Stored heat, yes, but radiation principally.

Or, how about how the ground still feels warm an hour after the sun sets. It's not radiating heat, as the ground itself is not a heat source.

Anything hot radiates. You notice the same walking near a wall that's been in the afternoon sun. That can't be convection or conduction.