IIRC, you need to spin the spikes in the shaft to clear a path so you can get into positions to shoot the crumbling walls. There are switches behind the walls that turn off the fans. You do so by lowering the Batmobile against the wall into the row of spikes. There are three numbered slopes that you could go down. You should use each slope starting at 1 to 3. When you lower yourself down to the spikes, you'll notice that there's some open space to either side of you. Move the Batmobile in that direction to spin the wall until you get the spray painted Bat symbol underneath you. That's when you know it's aligned correctly. Once aligned, you can move on to the next slope and that should give you a clear shot at the next wall. Repeat the process til you get to the third slope. You'll have to turn some of the upper layers of spikes back so you can clear a path. Look at the environment and figure out what to turn so you can go down the third slope as far as you can. Hopefully from here, you can figure out the rest.