A rotary machine includes a seal device capable of restricting a flow of a fluid in a clearance between a stationary member and a rotational member. The seal device includes a pressure loss element mounted to the stationary member, a first non-contact type seal protruding from the rotational member toward the pressure loss element and facing the pressure loss element via a first gap, and a second non-contact type seal protruding from the stationary member toward the rotational member, facing the rotational member via a second gap, and being positioned on one side of the pressure loss element in a flow direction of the fluid. The seal device also includes a contact type seal protruding from the stationary member toward the rotational member and being disposed downstream of the pressure loss element and the second non-contact type seal in the flow direction of the fluid.

A gas turbine engine having a bearing housing with a housing cavity and a shaft rotating about a rotation axis. One or more bearings support the shaft. A housing supporting the bearing and defining a chamber axially adjacent to the bearing. A seal assembly is in the housing between the chamber and an exterior of the chamber. The seal assembly includes a seal supported by the housing and surrounding the shaft so as to define an annular gap between an inner surface of the seal and an outer surface associated to the shaft, the gap defining a part of a sealing path of the seal assembly for air to flow from said exterior into the chamber. An impeller rotates with the shaft and located radially inward of the gap relative to the rotation axis, the impeller oriented to drive oil toward the bearing.

A circumferential seal assembly suitable for forming a thin film between a rotatable runner and a sealing ring is presented. The assembly includes an annular seal housing, a rotatable runner, an annular seal ring, and a plurality of groove structures. Each groove structure includes a groove and an optional feed groove. The groove includes at least two adjoining steps defined by base walls arranged to decrease depthwise. Two adjoining base walls are disposed about a base shoulder. Each base shoulder locally redirects a longitudinal flow to form an outward radial flow in the direction of the annular seal ring. The base walls are bounded by and intersect a pair of side walls. A side wall includes side shoulders which narrows the groove widthwise and locally redirects the longitudinal flow to form a lateral flow in the direction of the other side wall. Outward and lateral flows separately or in combination enhance stiffness of a thin-film layer between the annular seal ring and the rotatable runner.

A circumferential seal assembly suitable for forming a thin film between a rotatable runner and a sealing ring is presented. The assembly includes an annular seal housing, a rotatable runner, an annular seal ring, and a plurality of groove structures. Each groove structure includes a groove and an optional feed groove. The groove includes at least two adjoining steps defined by base walls arranged to decrease depthwise. Two adjoining base walls are disposed about a base shoulder. Each base shoulder locally redirects a longitudinal flow to form an outward radial flow in the direction of the annular seal ring. The base walls are bounded by and intersect a pair of side walls. A side wall includes side shoulders which narrows the groove widthwise and locally redirects the longitudinal flow to form a lateral flow in the direction of the other side wall. Outward and lateral flows separately or in combination enhance stiffness of a thin-film layer between the annular seal ring and the rotatable runner.

A turbine assembly includes a rotor assembly including a shaft coupled to a plurality of rotor stages including a plurality of turbine blades. The shaft and the plurality of turbine blades define a wheelspace therein. The turbine assembly further includes a plurality of seals in series, at least one seal of the plurality of seals is coupled between a static support member and a respective rotor stage such that a plurality of turbine cavities in series are defined within the wheelspace. Each turbine cavity of the plurality of turbine cavities defined by the plurality of seals receives a pressurized fluid flow that applies an axially aft force to the respective rotor stage of the plurality of rotor stages that at least partially reduces net rotor thrust generated by the rotor assembly during operation, the pressurized fluid flow further provides turbine purge within the wheel space.

A turbine assembly includes a rotor assembly including a shaft coupled to a plurality of rotor stages including a plurality of turbine blades. The shaft and the plurality of turbine blades define a wheelspace therein. The turbine assembly further includes a plurality of seals in series, at least one seal of the plurality of seals is coupled between a static support member and a respective rotor stage such that a plurality of turbine cavities in series are defined within the wheelspace. Each turbine cavity of the plurality of turbine cavities defined by the plurality of seals receives a pressurized fluid flow that applies an axially aft force to the respective rotor stage of the plurality of rotor stages that at least partially reduces net rotor thrust generated by the rotor assembly during operation, the pressurized fluid flow further provides turbine purge within the wheel space.

An assembly, more particularly a turbomachine, includes a shaft, which extends along an axis, a shaft seal device for sealing an annular gap between the shaft and a stator in order to seal a process fluid chamber in relation to the environment. The shaft seal device has a ferrofluid shaft seal. At the process fluid chamber, the shaft seal device includes, in addition to the ferrofluid shaft seal, an additional shaft seal. The ferrofluid shaft seal is arranged at the annular gap axially between the first shaft seal and the environment. A pressure sink is provided at the annular gap axially between the additional shaft seal and the ferrofluid shaft seal.

An assembly, more particularly a turbomachine, includes a shaft, which extends along an axis, a shaft seal device for sealing an annular gap between the shaft and a stator in order to seal a process fluid chamber in relation to the environment. The shaft seal device has a ferrofluid shaft seal. At the process fluid chamber, the shaft seal device includes, in addition to the ferrofluid shaft seal, an additional shaft seal. The ferrofluid shaft seal is arranged at the annular gap axially between the first shaft seal and the environment. A pressure sink is provided at the annular gap axially between the additional shaft seal and the ferrofluid shaft seal.

A gas turbine engine includes a combustion section, a turbine section, and a compressor section. The combustion section includes a combustor casing, a combustor, a cooling duct, and an outer duct. The combustor casing defines at least in part a diffuser cavity and a fluid inlet. The combustor disposed is in the diffuser cavity. The cooling duct is in fluid communication with the fluid inlet in the combustor casing and is configured to transport a flow of cooled air. The outer duct surrounds at least a portion of the cooling duct and extends along a portion of an entire length of the cooling duct. The outer duct defines a gap with the cooling duct and is configured to transport a flow of buffer air. The turbine section is disposed downstream from the combustion section. The cooling duct is in fluid communication with the turbine section.

Methods and systems for controlling infiltration of ambient air into, and exfiltration of process gas out of, an organic Rankine system. A system comprises a first sealing mechanism configured to seal at least one shaft against exfiltration of a process gas when the turbomachine is operating. The system further comprises a second sealing mechanism configured to seal the at least one shaft against infiltration of ambient air when the system is in a standstill mode. The system further comprises one or more pressure sensors configured to detect a pressure of gas within the system to monitor whether infiltration of ambient air has occurred and a system purge is needed.