Convection fan, Chinese pig box

Convection smoker!,?? China box la caja china box, Cuban pig box! Has any one tried a convection fan in a Cuban pig box. The air is trapped in the box with charcoal cooking on top. I would add the pig and maybe a pan of water in the inclosures. See Cuban Chinese pig roaster in Miami la caja china is the name.
Does anyone know anything about adding a convection fan?