indirect??????

Mop · November 2000

This is a serious question and is not intended to be sarcastic.
I lurk in this forum and often hear the term "indirect"
I fully understand the meaning of indirect as I cook this way all the time in a non BGE cooker,..My question is, "how do you cook indirectly in a cooker the shape of the BGE?
The heat is directly under the food, unlike having the fire on one side and the food on the other..
just curious....[p]Great pics of the Eggtoberfest by the way, looks like there were some superb food as well as superb people.
Mop

JJ · November 2000

Mop,
By the use of a drip pan, pizza stone, plate sitter or any other object that will shield the food from direct contact with the heat source.

Spin · November 2000

Mop,[p]Indirect requires that the meal is not exposed to the direct heat of the fire. Placing a pizza stone (or other heat buffer) between the meal and the fire forces the airflow (heat) along the the inside surface of the Egg (towards the top vent) and around the meal.[p]The meal does cook in a sheltered area. The airflow is only the movement of air necessary to feed the fire to maintain the cooking temp. Once the ceramic comes to temp, little heat is needed to maintain the cooking temp. The fire then only needs to be hot enough to equal the heat losses.[p]Spin[p]Spin[p]

Mop · November 2000

Thanks guys, that makes sense.......

Mike Oelrich · November 2000

Mop,[p] If you prefer, you can to think about indirect vs. direct coloking from a thermodynamics perspective. There are three forms of heat transfer: conduction, convection, and radiation. We are all most familiar with conduction, which is the spread of energy through an object when certain parts of the object are hotter than others (think cast iron pans here), or between two objects when they touch. We are also fairly familiar with convection, which is heat transfer through a moving fluid. In general, a hotter fluid tend to be less dense than a colder fluid so the hotter one tends to rise. This convection causes heat to be distributed in a system (and causes the smoke to rise out of the top of the BGE). Radiation is the one folks usally don't think about. It is the direct transfer of energy from the heat source via electromagnetic waves. This type of heat transfer can even happen in a vacuum (think "Sun"). In the BGE, the food conducts heat from the grid or cooking surface, recieves heat from the convection of the hot air generated by the coals and receives heat by radiation from the coals as well as the ceramics in the BGE "shell" (which, in a properly preheated BGE is also warm at this point). By putting another layer in between the coals and the food, you add an extra step in the chain of heat transfer, therefore moderating the amount of radiation the food receives from below. Basically, the stuff (I'll say firebricks) you put in between the coals and the food is absorbing the radiative heat from the coals, and this energy is transfered via conduction to the other side of the fire bricks, then re-radiated (or carried away by convection) from there. Since ceramics, in general, are good insulators (and therefore, bad conductors), the conduction isn't very efficient and a temperature difference is created across the firebrick ensuring that the energy radiated at the food is less than it would be if it were directly over the coals. The firebricks must have enough space around them to allow the rest of the heat from the coals to flow via convection (air being the fluid in this case) to the food. The end result is that the food is heated more evenly. In the strictest sense, since the food is still receiving direct radiative heat from the firebricks and the BGE "shell", calling this method "indirect" isn't totally accurate. However, for our purposes, it makes a lot of sense. My apologies for any glaring inaccuracies that those more into physics than myself might wish to point out.[p]MikeO

Cat · November 2000

MikeO,[p]Wow. GREAT explanation![p]Cathy

Mop · November 2000

Wow is right.....I hardly doubt anyone can top that explanation.......thanks.....
Mop

Char-Woody · November 2000

MikeO, You get a A+ for explaining how the ceramic firebrick and/or Tri Pod plate sitter works. I enjoyed it.
C~W[p]

MAC · November 2000

MikeO,
That explaination should be a three credit class somewhere. GRRR...ATE Job ! !
MAC

Unknown · November 2000

MikeO,[p]I'm impressed!!!

indirect??????

Comments

Categories