General principle of IEM Rotary Debarkers. Note the heavy loading on the low rotor side.
The rotors move the bottom layers of wood upwards where they spill out and cascade back to the low rotor side wall.
The wood charge then settles down and the next layers are abraded while it is moved upwards.
During this process the entire charge undergoes a fluidized and predictable log on log contact to remove the
loosened bark which falls thru the rotor array.