A blower includes a power supply unit drivingly coupled to a fan assembly including a plurality of fan stages via an input shaft coupled to the fan stages. Each fan stage includes a housing, a plurality of stationary vanes, and a fan including blades extending radially away from a hub. The fan stages are non-identical, and include fans having varied characteristics such as hub diameter, blade length, axial blade width, blade twist, and/or blade orientation. For example, the diameter of the fan hubs may increase moving in a downstream direction. In addition, the fan assembly may be a stand-alone unit or attachment having an input shaft pro trading from the fan assembly that is configured to be coupled to a generic power supply unit for operating the fan assembly.
