Abstract: An turbocharger includes a parallel twin-impeller compressor and separate inlets into the two impellers. A first or outboard impeller receives one stream of inlet air and a second or inboard impeller receives its own separate stream of inlet air by way of a generally annular inlet volute surrounding the inlet to the second impeller. Air is fed from the inlet volute radially inwardly through a feed passage to the inlet to the second impeller. A plurality of inlet guide vanes are located in the feed passage for the second impeller, the inlet guide vanes creating a swirling air stream into the second impeller. Introduction of swirl to the second impeller alters the flow distribution between the impellers and affects the stability of the overall stage.

Abstract: A flow-control assembly may include a fluid conduit and a flow-control valve in the fluid conduit. The flow-control assembly may further include a fluid expansion conduit with an inlet defined at least in part by the fluid conduit and configured to selectively receive flow of a fluid from the fluid conduit. The fluid expansion conduit may further include an outlet in fluid communication with the fluid conduit downstream of the flow-control valve. A rotating fluid expander in the fluid expansion conduit may be configured to expand the fluid and thereby rotate and in some embodiments generate electricity. In a first position flow is substantially blocked. In a second position flow is allowed through the fluid expansion conduit. In a third position flow through the fluid conduit is allowed without necessarily passing through the fluid expansion conduit. Related systems and methods are also provided.

Abstract: A single-shaft exhaust gas-driven turbocharger includes two parallel-flow first-stage centrifugal compressors in series with a single second-stage centrifugal compressor, and a one-stage turbine arranged to drive both the first- and second-stage centrifugal compressors via a single shaft on which the compressors and turbine are fixedly mounted. The compressor housing defines from one to a plurality of circumferentially spaced inlet ducts for the second wheel of the first stage, and from one to a plurality of circumferentially spaced interstage ducts leading from a vaneless diffuser of the first stage into the inlet of the second stage.

Abstract: An engine system includes an internal combustion engine and an air intake assembly configured to supply a flow of air to one or more cylinders of the internal combustion engine. The air intake assembly includes an air supply conduit with a turbine therein, a bypass conduit configured to bypass the turbine, and a fresh air valve configured to selectively direct the flow of air to one or both of the air supply conduit and the bypass conduit. An exhaust conduit is configured to receive a flow of exhaust gas from the internal combustion engine and direct the flow of exhaust gas away from the internal combustion engine. A compressor in the exhaust conduit, which may be coupled to the turbine by a shaft, is configured to rotate and thereby reduce backpressure in the exhaust conduit during idle and partial throttle conditions.

Abstract: A flow-control assembly may include a fluid conduit and a flow-control valve in the fluid conduit. The flow-control assembly may further include a fluid expansion conduit with an inlet defined at least in part by the fluid conduit and configured to selectively receive flow of a fluid from the fluid conduit. The fluid expansion conduit may further include an outlet in fluid communication with the fluid conduit downstream of the flow-control valve. A rotating fluid expander in the fluid expansion conduit may be configured to expand the fluid and thereby rotate and in some embodiments generate electricity. In a first position flow is substantially blocked. In a second position flow is allowed through the fluid expansion conduit. In a third position flow through the fluid conduit is allowed without necessarily passing through the fluid expansion conduit. Related systems and methods are also provided.

Abstract: A single-shaft exhaust gas-driven turbocharger includes two parallel-flow first-stage centrifugal compressors in series with a single second-stage centrifugal compressor, and a one-stage turbine arranged to drive both the first- and second-stage centrifugal compressors via a single shaft on which the compressors and turbine are fixedly mounted. The compressor housing defines from one to a plurality of circumferentially spaced inlet ducts for the second wheel of the first stage, and from one to a plurality of circumferentially spaced interstage ducts leading from a vaneless diffuser of the first stage into the inlet of the second stage.