The Variable Burn Pattern Smokers utilizes a rack with a “U” pattern underneath the removable diverter to heat the smoker. This means the amount of “fire” is controlled by the amount of oxygen that is allowed in through the front butterfly vents. Without the butterfly vents open, the fuel can’t fully ignite because there isn’t sufficient oxygen in the heat chamber. So the burning area of fuel is contained in the VBP rack. where there are slotted vents in the front and back of the cook chamber that allow the heat/smoke to transfer upward from the VBP into the cook chamber. Once inside the cook chamber, the divider plate evenly distributes the air and heat and allows the natural convection process to begin. Once this process has started air and heat movement naturally drafts up in a convected motion around the smoker and out through the exhaust stack.
So by controlling the amount of oxygen that is fed in, we can control the amount of “fire” or the temp in the cook chamber. The heat/smoke moves through the cook chamber of a variable burn pattern much slower than in a typical offset stick burner smoker. Therefore the cook chamber doesn’t dry out as much either — this creates a nice moist cooking environment that doesn’t tend to cause meat to dry out as fast while it is cooking.