A blower assembly for a heating, ventilation, and/or air conditioning (HVAC) system includes a centrifugal fan having a fan wheel. A plurality of blades are coupled to the fan wheel at an inner blade boundary and extend radially to an outer blade boundary. The blower assembly includes a first housing panel and a second housing panel disposed on opposite sides of the centrifugal fan and extending transverse to the centrifugal fan. The blower assembly includes a wall extending between the first housing panel and the second housing panel and a flange extending from the wall at a vertex. The flange extends outwardly from the wall. A first radial distance from the vertex to the outer blade boundary is between 4 percent and 20 percent of a second radial distance from a rotational axis of the centrifugal fan to the outer blade boundary.

A turbine comprises a turbine wheel for rotation within a turbine housing, the turbine housing including at least one volute arranged to deliver a fluid to the turbine wheel via the turbine nozzle. A method for determining a width of a turbine nozzle for the turbine, comprises selecting from a relationship between a turbine stage efficiency and an effective nozzle area, at least one target effective nozzle area. As used here, the effective nozzle area is dependent on both the width of the turbine nozzle and a whirl angle induced by the at least one volute. The method further comprises determining, in dependence on the whirl angle, the width of the turbine nozzle as a width that will achieve the at least one target effective nozzle area.

An air duct component includes first and second volute members arranged oppositely in a cross section perpendicular to an axis of a cross-flow impeller. An inner end of the first volute member includes a volute tongue. A cross-flow air duct formed between the first and second volute members includes a middle air duct section and an end air duct section arranged along an axial direction of the cross-flow impeller. The middle air duct section includes a middle air outlet duct located downstream of a vertical line that passes through the volute tongue and is perpendicular to the second volute member. The end air duct section includes an end air outlet duct located downstream of the vertical line. A cross-sectional area of the middle air outlet duct is larger than a cross-sectional area of the end air outlet duct.

A centrifugal fan includes: a fan, blades; and a scroll casing housing the fan, the scroll casing including a discharge portion, and a scroll portion including a side wall, a circumferential wall, and a tongue portion. In the circumferential wall, at a first end between the circumferential wall and the tongue portion, and at a second end between the circumferential wall and the discharge portion, a distance between an axis of the rotational shaft and the circumferential wall is equal to a distance between the axis of the rotational shaft and a standard circumferential wall, and is greater than or equal to the distance between the first end and the second end of the circumferential wall, the circumferential wall including a plurality of extended portions between the first end and the second end of the circumferential wall.

The invention relates to a fan housing (1), a fan and an operating system having a fan. The fan housing (1) has a volute shape and includes a volute tongue (2) and a cavity (16) between an air inlet and an air outlet, the volute tongue is provided with a protrusion (20) configured to extend in a direction substantially parallel to an axial direction of an impeller mounted in the cavity and has at least one peak (24) in a longitudinal section of the fan housing, and the peak is opposed to an annular projection (32) located at the circumferential outer surface of the impeller. The use of the invention can effectively reduce the noise level during the operation of the fan and improve fan performance, thereby considerably improving users' comfort and satisfaction.

A blower assembly for a heating, ventilation, and/or air conditioning (HVAC) system includes a centrifugal fan having a fan wheel. A plurality of blades are coupled to the fan wheel at an inner blade boundary and extend radially to an outer blade boundary. The blower assembly includes a first housing panel and a second housing panel disposed on opposite sides of the centrifugal fan and extending transverse to the centrifugal fan. The blower assembly includes a wall extending between the first housing panel and the second housing panel and a flange extending from the wall at a vertex. The flange extends outwardly from the wall. A first radial distance from the vertex to the outer blade boundary is between 4 percent and 20 percent of a second radial distance from a rotational axis of the centrifugal fan to the outer blade boundary.

A blower assembly for a heating, ventilation, and/or air conditioning (HVAC) system includes a centrifugal fan having a fan wheel. A plurality of blades are coupled to the fan wheel at an inner blade boundary and extend radially to an outer blade boundary. The blower assembly includes a first housing panel and a second housing panel disposed on opposite sides of the centrifugal fan and extending transverse to the centrifugal fan. The blower assembly includes a wall extending between the first housing panel and the second housing panel and a flange extending from the wall at a vertex. The flange extends outwardly from the wall. A first radial distance from the vertex to the outer blade boundary is between 4 percent and 20 percent of a second radial distance from a rotational axis of the centrifugal fan to the outer blade boundary.

A fan unit that forms part of a gases supply unit used as part of a breathing assistance system for providing heated gases to a user. The fan has an impeller surrounded by an upwardly sloped surface to facilitate improved airflow performance under surge conditions.

A compressor housing may include a shroud portion which is axially spaced from an inlet portion and configured to at least partially surround the compressor wheel. The compressor housing may be further configured to include a recirculation cavity which is formed between an exterior surface of the shroud portion and an interior surface of the compressor housing. Furthermore, a recirculation slot may define an airflow pathway between the recirculation cavity and the compressor wheel. Additionally, the compressor housing may include an angled shroud support extending radially through the recirculation cavity from the exterior surface of the shroud portion to the interior surface of the compressor housing. The angled shroud support may be spaced an axial distance away from the recirculation slot to reduce turbulence in the airflow as the airflow moves from the recirculation cavity to the compressor wheel.

A shaftless rotary machine includes an impeller, a motor positioned radially outward from the impeller, and a housing. The impeller includes a hub, blades connected to the hub, and a shroud connected to the blades. The motor includes a rotor connected to the shroud and a stator. The housing includes an inlet, an outlet, and a duct. The duct extends from the inlet to the outlet. The duct partially surrounds the motor and the impeller.