Example embodiments relate to a temperature control device for controlling the temperature of air. The temperature control device including a fan and a blow-out area in a housing, the fan moving air to the blow-out area, a sound wave-effective body being arranged in the blow-out area, and the sound wave-effective body being part of a compensating ring for producing an air duct adjacent to the blow-out area.

A shroud for an air moving device includes a shroud body configured to at least partially surround one or more blades. The shroud body defines an annular cavity and an annular opening. The annular opening faces the one or more blades. The shroud also includes a Helmholtz resonator defined by the annular cavity and the annular opening. The Helmholtz resonator is configured to reflect sound generated by the one or more blades out of the shroud body.

A gas turbine engine according to an aspect of the present disclosure includes, among other things, a propulsor section, a compressor section including a first compressor and a second compressor, and a turbine section including a first turbine and a second turbine. The first compressor includes a plurality of arrays of airfoils defining a plurality of compressor stages. A number of airfoils in each downstream array of the plurality of arrays is a factor (F) of a number of airfoils in a respective immediately upstream array of the plurality of arrays. The factor (F) is between 1.19 and 1.55 for each of the downstream arrays of the first compressor.

An air conditioner includes a cross-flow fan having a cylindrical shape, and a heat exchanger disposed on an upstream side of an air flow of the cross-flow fan. The cross-flow fan includes a plurality of impellers. Each of the impellers includes a plurality of blades arranged in a circumferential direction. The heat exchanger has an inverted V-shape. A clearance is formed between the cross-flow fan and the heat exchanger. The clearance has a dimension no more than 20% of a diameter of each of the impeller. The impellers are arranged with at least one of the blades displaced between each adjacent two of the impellers. A number of the impellers arranged along a rotation axis is at least 14 and no more than 30 in the cross-flow fan. Each of the plurality of impellers being connected together to form a single, continuous unit without a gap disposed between adjacent impellers.

Blowers having noise reduction features are provided. A blower may include a main body defining an airflow path therethrough, the main body extending between and defining an inlet end and an outlet end. The blower may further include an inlet muffler provided at the inlet end. The inlet muffler includes a plurality of inlet ports, each of the plurality of inlet ports including a peripheral surface defining a port aperture therethrough. At least one of the plurality of inlet ports further includes a damper material provided on the peripheral surface of the at least one inlet port and further defining the port aperture therethrough.

A hand-guided working apparatus has a radial fan. The radial fan includes a fan impeller and an air duct, which has a spiral portion surrounding the fan impeller and has a duct cross section, which increases in the air flow direction. An outlet funnel portion adjoins the spiral portion, widens in a funnel shape in the air flow direction and has a radially inner boundary wall and a radially outer boundary wall. The outlet funnel portion ends in an air outlet opening, the outlet width of which is smaller than an outside diameter of the fan impeller. The radially inner and/or the radially outer boundary wall of the outlet funnel portion has a curvature opposed to that of the spiral portion. An intermediate wall is arranged in the outlet funnel portion, between the radially inner and the radially outer boundary wall. The intermediate wall extends with a curvature opposed to that of the spiral portion and divides the outlet funnel portion into two component portions, each widening in the shape of a funnel in the air flow direction.

Blowers having noise reduction features are provided. A blower may include a main body defining an airflow path therethrough, the main body extending between and defining an inlet end and an outlet end. The blower may further include an inlet muffler provided at the inlet end. The inlet muffler includes a plurality of inlet ports, each of the plurality of inlet ports including a peripheral surface defining a port aperture therethrough. At least one of the plurality of inlet ports further includes a damper material provided on the peripheral surface of the at least one inlet port and further defining the port aperture therethrough.

A propulsion assembly includes a fan and a fan case system disposed about the fan. The fan case system includes at least one perforated portion including a plurality of holes. The propulsion assembly further includes at least one acoustic panel mounted to the exterior surface of the fan case system coincident with the at least one perforated portion. The at least one acoustic panel includes a core including a plurality of cells extending between a first side of the core and a second side of the core. The at least one acoustic panel further includes a back skin attached to the second side of the core. The first side of the core is in contact with the exterior surface of the fan case system to form a plurality of resonant cavities defined by the plurality of holes, the plurality of cells, and the back skin.

A blower includes a stationary portion including an inlet and an outlet, a rotating portion provided to the stationary portion, and a motor adapted to drive the rotating portion. The inlet and outlet are co-axially aligned. The stationary portion includes a housing, a stator component provided to the housing, and a tube providing an interior surface. The rotating portion includes one or more bearings that are provided along the interior surface of the tube to support a rotor within the tube. In an embodiment, the blower is structured to supply air at positive pressure.

A blower configured to be positioned in confined spaces and to provide ventilation of a fluid, such as temperature controlled air, is disclosed. In various embodiments, the blower is configured to have a reduced axial thickness, which can be desired in such confined spaces. In some embodiments, the blower has an integral filter, a wire channel for the routing of one or more wires, and/or an exposed backplate. In some embodiments, the blower has a snap-fit circuit board, containment system for mounting the motor, one or more vanes for directing fluid flow, shrouded impeller, and/or integrated connector.