Abstract: In a multi-blade centrifugal fan in which an impeller is provided in a scroll casing in a freely rotatable manner, the scroll casing is provided with an axially expanded portion that forms an air channel at a bottom surface thereof which is expanded in a rotation-axis direction at a radially outer side of an annular flange portion which supports the impeller; and is provided, in a region of an outlet between a tongue portion and a spiral-end portion of the scroll casing in the axially expanded portion, with a protrusion that protrudes radially outward from a radially inner side surface by a predetermined amount so as to directly face an airflow in a circumferential direction.

Abstract: In a vehicle heat-exchange module in which a fan unit is provided at the downstream side of a rectangular heat exchanger, and the fan unit is provided with a shroud having a bell-mouth and an annular opening, a propeller fan that is disposed in the annular opening, and a fan motor that rotationally drives the propeller fan, the fan unit is a unit having a single-fan configuration in which motor input power is at a predetermined level or less, and the propeller fan is provided with two sets of winglets that are respectively constructed upright, with a prescribed gap therebetween in the radial direction, along the circumferential direction on both a pressure surface and a suction surface of the root side of the blades.

Abstract: In a multi-blade centrifugal fan in which an impeller is provided in a scroll casing in a freely rotatable manner, the scroll casing is provided with an axially expanded portion that forms an air channel at a bottom surface thereof which is expanded in a rotation-axis direction at a radially outer side of an annular flange portion which supports the impeller; and is provided, in a region of an outlet between a tongue portion and a spiral-end portion of the scroll casing in the axially expanded portion, with a protrusion that protrudes radially outward from a radially inner side surface by a predetermined amount so as to directly face an airflow in a circumferential direction.

Abstract: In a vehicle heat-exchange module in which a fan unit is provided at the downstream side of a rectangular heat exchanger, and the fan unit is provided with a shroud having a bell-mouth and an annular opening, a propeller fan that is disposed in the annular opening, and a fan motor that rotationally drives the propeller fan, the fan unit is a unit having a single-fan configuration in which motor input power is at a predetermined level or less, and the propeller fan is provided with two sets of winglets that are respectively constructed upright, with a prescribed gap therebetween in the radial direction, along the circumferential direction on both a pressure surface and a suction surface of the root side of the blades.