Exhausted Spark, Morning.
I built a smoker a few years back with a fan. It had a somewhat long shaft between the motor and blade. It is installed at the bottom of the smoke box. The shroud is to keep stuff off of the motor. The aluminum plate is to open/close the exterior air supply. It allows a once thru air flow or a recirculating air flow, and the motor stays cool. With the heat on, you can easily dry meat. If I had an "Amazing Smoke Generator" when I built this set up, it would have been the perfect cold smoker.
Looking down on the fan assembly. The shroud on the motor. The fan shroud. A deflector plate to redirect the air flow inside the smoke box. The fan shroud has an opening for recirculating inside air.
This shows the air intake to the fan, CLOSED. Pretty much all the smoke and heat is being recirculated at this setting.
When I lived on the coast, (Bellingham) this allowed for the heat to be on, and dry the meat, before adding smoke. When it rains all the time and the humidity is 90% this was a necessary addition.
There are many ways to use this type set-up. It mimicks professional smokehouses.