A blower includes a first fan stage with a first housing that has a first plurality of stationary vanes and a first fan that has a first plurality of blades extending radially outwardly from a first hub. The first housing includes a first axial end and a second axial end opposite the first axial end. The blower also includes a second fan stage coupled to the first fan stage. The second fan stage includes a second housing with a second plurality of stationary vanes and a second fan that has a second plurality of blades extending radially outwardly from a second hub. The second fan stage includes a third axial end and a fourth axial end opposite the third axial end. The first hub and/or the second hub has a frustoconical shape that converges from the first axial end toward the fourth axial end.
