A tube gallery for a gas turbine engine includes a body. The body includes an external surface. The body also includes a plurality of channels defined in the body. Each channel includes an inlet disposed on the external surface, an outlet spaced apart from the inlet and disposed on the external surface, and a passage extending between and fluidly communicating the inlet to the outlet. The passage of each channel has a non-circular cross-sectional shape. The non-circular cross-sectional shape has a first maximum dimension along a first direction and a second maximum dimension along a second direction orthogonal to the first direction. The first maximum dimension is greater than the second maximum dimension by a factor of at least 1.2.

An impulse turbine of a turbine device includes a cylindrical body having an axial hole, and a blade unit arranged to surround the periphery of the body. The blade unit includes a cylindrical base arranged to surround the periphery of the body, and a plurality of unit blades radially arranged in a line along the periphery of the base. Each of the unit blades includes an outlet that discharges fluid, injected onto the unit blade, in a direction different from the fluid spray direction, but does not discharge the fluid toward the other unit blades.

Disclosed are an impulse turbine and a turbine device. The disclosed impulse turbine includes a cylindrical body having an axial hole, and a blade unit arranged to surround the periphery of the body. The blade unit includes a cylindrical base arranged to surround the periphery of the body, and a plurality of unit blades radially arranged in a line along the periphery of the base. Each of the unit blades includes an outlet that discharges fluid, injected onto the unit blade, in a direction different from the fluid spray direction, but does not discharge the fluid toward the other unit blades.

Disclosed is a ventilator with an electrical drive and at least one rotating or non-rotating functional unit associated with the drive or with a structural component of the drive for generating and/or influencing an air current, wherein the functional unit is arranged coaxially around the drive or in front of it or after it, and wherein the association takes place directly or indirectly in a positive and non-positive manner by the intermeshing and mutual bracing of connection means.

In a cross section of a flow passage formed to conduct a flow of air from an inside/outside air box to an upper air passage of a scroll casing while the cross section of the flow passage is taken along an imaginary plane which includes an outer edge of an air guide plate and is parallel to a rotational axis of an impeller, a passage section, which is located on one radial side of a separation tube where a nose of the scroll casing is placed, is defined as a first opening section, and another passage section, which is located on an opposite radial side of the separation tube, which is opposite to the nose, is defined as a second opening section. A passage cross-sectional area of the second opening section is larger than a passage cross-sectional area of the first opening section.

A heating, ventilation, and/or air conditioning (HVAC) system includes a compressor having an impeller configured to rotate and drive a working fluid through a working fluid circuit of the HVAC system in an active operating mode. The HVAC system further includes a controller configured to, in response to receiving an input indicative of a transition to operate in an inactive operating mode, suspend the active operating mode by interrupting a supply of power to the compressor, adjust pre-rotation vanes of the compressor, a variable geometry diffuser of the compressor to a first position, or both to enable a backflow of the working fluid through the compressor for a first interval of time, and, after the first interval of time has elapsed, adjust the pre-rotation vanes, the variable geometry diffuser, or both to a second position to block the backflow of the working fluid through the compressor.

In a cross section of a flow passage formed to conduct a flow of air from an inside/outside air box to an upper air passage of a scroll casing while the cross section of the flow passage is taken along an imaginary plane which includes an outer edge of an air guide plate and is parallel to a rotational axis of an impeller, a passage section, which is located on one radial side of a separation tube where a nose of the scroll casing is placed, is defined as a first opening section, and another passage section, which is located on an opposite radial side of the separation tube, which is opposite to the nose, is defined as a second opening section. A passage cross-sectional area of the second opening section is larger than a passage cross-sectional area of the first opening section.

A pump includes an axial inducer. The axial inducer includes a housing that has an internal surface that defines an axial fluid passage. A rotor is disposed about a central axis in the fluid passage. The rotor includes at least one blade that defines at least one blade tip. The internal surface of the housing defines a plurality of grooves adjacent the at least one blade tip. The grooves are elongated in a circumferential direction.

A scroll shape of a compressor forms into a spiral shape a flow path of fluid discharged from a diffuser provided on a downstream side of the compressor in a fluid flow direction. The scroll shape has a scroll outer diameter that is not constant in a circumferential direction. An increase degree of a ratio A/R is set to be increased in a range from a winding start position to a winding end position of a scroll portion where A is a passage cross-sectional area of the scroll portion and R is a radius from a center of the compressor to a center of a passage cross section of the scroll portion.

A turbine housing defining a pair of volutes with respective outlets divided by a divider wall, includes a diffuser space in the gas flow path between the volutes and the turbine wheel. The diffuser space has an upstream portion having a smaller axial extent than a downstream portion of the diffuser space. The widening of the diffuser space tends to direct exhaust gas entering the diffusion space from at least one side of the divider wall towards the corresponding axial end of the diffuser space. Thus reduces the tendency of this gas to interrupt the flow into the diffuser space of exhaust gas from the other inlet volute.