A flow-straightener vane of a bypass turbomachine includes a plurality of vane sections stacked radially with respect to a longitudinal axis (X) along a stacking line (L) between a root end and a tip end. Each vane section has a pressure-face surface and a suction-face surface extending axially between an upstream leading edge and a downstream trailing edge. Between the leading and trailing edges of each vane section there is formed a profile chord (CA) the length of which is substantially constant between the tip end and the root end, and the stacking line (L) exhibits a curvature in a plane passing more or less through the axis (X) and through the stacking line (L), situated in the vicinity of the tip end and oriented from downstream towards upstream.

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. 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.

A blower may include a fan, a casing including a discharge port and housing the fan, and a nozzle attachable to the discharge port. The nozzle may include a nozzle tube in which air flows, and a plate member disposed within the nozzle tube. A rear end surface of the plate member may be inclined to a flow direction in which air flows within the nozzle tube.

A centrifugal compressor for a chiller includes an impeller, a motor, a diffuser, and at least one injection port. The impeller is attached to a shaft rotatable about a rotation axis. The motor is arranged and configured to rotate the shaft in order to rotate the impeller. The diffuser is disposed downstream from the impeller. The at least one injection port is located within the diffuser. The at least one injection port is configured and arranged to supply liquid refrigerant into the diffuser from a condenser or an economizer of the chiller.

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.

An exemplary section of a gas turbine engine according to this disclosure includes, among other things, a first array of airfoils including a first number of airfoils, and a second array of airfoils downstream of the first array of airfoils. The second array includes a second number of airfoils. The second number of airfoils is at least 1.19 times the first number of airfoils thereby providing a predetermined modal.

Disclosed is a noise reduction device for heat dissipation fans, the noise reduction device being applied to a heat dissipation fan with an interference structure for rotor and stator blades, wherein the noise reduction device comprises a duct formed at an end portion of a through-flow area of the heat dissipation fan, the inner diameter D of the duct is determined by the size and the rotation speed of the heat dissipation fan, and the axial length L of the duct is determined by an acoustic cutoff condition of the heat dissipation fan.

A fan frame turbulence structure includes a frame body having a wind incoming side and a wind outgoing side respectively on two sides of the frame body. The frame body defines an airflow passage which passes through the frame body from the wind incoming side to the wind outgoing side. The wind incoming side has an inlet in communication with the airflow passage. The inlet has a breaking section between the wind incoming side and the passage inner wall. The breaking section includes densely distributed breaking units. The breaking units define therebetween gaps in communication with the airflow passage. The breaking units serve to break and fracture airflow sucked in from the wind incoming side, whereby part of the airflow passes through the gaps between the breaking units and is broken and fractured into multiple gap turbulences to flow into the air passage so as to lower the wideband noise.

A fan is provided that includes a fan blade movable relative to a housing. The housing and the fan blade are configured such that the fan generates a pink noise sound profile both when air is exiting the fan housing through an air outlet vent and when air is not exiting the housing through the outlet air vent.

An axial-flow fan includes an impeller including plural blades fixed to an outer peripheral portion of the hub and each surrounded by an inner peripheral edge, an outer peripheral edge, a leading edge, and a trailing edge. The leading edge is forward-curved in a rotational direction with an angle increasing to outer periphery of the impeller and runs toward an outer periphery up to point A, the trailing edge is forward-curved in the rotational direction and runs toward the outer periphery up to point D, recedes in the rotational direction of the impeller as the trailing edge runs toward the outer periphery up to point A′ located closer to the outer periphery than point D is to the outer periphery, advances in the rotational direction of the impeller in a region between point A′ and point B′, and reflexed at point D and point A′.