A positive displacement roots blower can include a housing having an inlet structured to receive an incoming flow of a fluid, an outlet structured to receive an outgoing flow of the fluid, and a passage. The positive displacement roots blower can also include a pair of intermeshed rotating members supported for complementary rotation within the housing, where the rotating members and the housing form respective operating volumes there between which rotate with the rotating members. Each of the respective operating volumes has the following regions: (1) open to inlet/closed to outlet; (2) closed to inlet/closed to outlet; and (3) closed to inlet/open to outlet. The passage includes a restriction and connects to at least one of the operating volumes when the at least one of the respective operating volumes is in region (2). The restriction can be a venturi feedback connecting to the outlet.

A system and medium for controlling a fuel gas compressor of a gas turbine system that compresses a gaseous fuel for consumption in a high-pressure combustor. Moreover, the compressor is configured to generate a discharge pressure for the combustor based at least in part on a load demand for the gas turbine system.

Liquid ring pumps are used to pump a variety of fluid types. Corrosive fluids are easily handled by the work fluid but can cause corrosion of pumping mechanisms. The present invention provides a magnetically driven liquid ring pump with corrosion resistant pumping mechanisms which achieves a longer time between service intervals.

Liquid ring pumps are used to pump a variety of fluid types. Corrosive fluids are easily handled by the work fluid but can cause corrosion of pumping mechanisms. The present invention provides a magnetically driven liquid ring pump with corrosion resistant pumping mechanisms which achieves a longer time between service intervals.

An air compressor according to an embodiment, which includes a cylinder and a rotating body provided to be rotatable around a rotation axis in the cylinder so as to generate compressed air through intake and exhaustion caused by rotation of the rotating body, includes an intake valve. The intake valve takes air in the intake and exhaustion. The intake valve is provided in the cylinder.

An air compressor according to an embodiment, which includes a cylinder and a rotating body provided to be rotatable around a rotation axis in the cylinder so as to generate compressed air through intake and exhaustion caused by rotation of the rotating body, includes an intake valve. The intake valve takes air in the intake and exhaustion. The intake valve is provided in the cylinder.

A positive displacement roots blower can include a housing having an inlet structured to receive an incoming flow of a fluid, an outlet structured to receive an outgoing flow of the fluid, and a passage. The positive displacement roots blower can also include a pair of intermeshed rotating members supported for complementary rotation within the housing, where the rotating members and the housing form respective operating volumes there between which rotate with the rotating members. Each of the respective operating volumes has the following regions: (1) open to inlet/closed to outlet; (2) closed to inlet/closed to outlet; and (3) closed to inlet/open to outlet. The passage includes a restriction and connects to at least one of the operating volumes when the at least one of the respective operating volumes is in region (2). The restriction can be a venturi feedback connecting to the outlet.

A positive displacement roots blower can include a housing having an inlet structured to receive an incoming flow of a fluid, an outlet structured to receive an outgoing flow of the fluid, and a passage. The positive displacement roots blower can also include a pair of intermeshed rotating members supported for complementary rotation within the housing, where the rotating members and the housing form respective operating volumes there between which rotate with the rotating members. Each of the respective operating volumes has the following regions: (1) open to inlet/closed to outlet; (2) closed to inlet/closed to outlet; and (3) closed to inlet/open to outlet. The passage includes a restriction and connects to at least one of the operating volumes when the at least one of the respective operating volumes is in region (2). The restriction can be a venturi feedback connecting to the outlet.

The invention relates to a turbine engine, such as a turbojet engine or a turboprop engine of an aeroplane, including at least one oil circuit (8) and cooling means (16) for cooling the oil of said circuit (8), the cooling means (16) including a refrigerant circuit (17) provided with a first heat exchanger (18) capable of exchanging heat between the refrigerant and the air and forming a condenser, a second heat exchanger (19) capable of exchanging heat between the refrigerant and the oil of the oil circuit and forming an evaporator, a pressure reducer (20), a compressor (21) and first regulator means (31) capable of regulating the pressure of the refrigerant entering the first exchanger (18).

A compressor 12 for use in a refrigerant circuit 11 using a refrigerating machine oil 60 being free of phosphoric ester and a refrigerant mixture inclusive of 1,1,2-trifluoroetylene includes a rolling piston 32 and a vane 33 in contact with the rolling piston 32 in a slidable manner. The rolling piston 32 and the vane 33 are formed of a base metal, the base metal being steel, and the base metal is exposed at a contact portion between the rolling piston 32 and the vane 33.