A bearing device for an exhaust gas turbocharger, comprising a first radial bearing and a second radial bearing, the radial bearings radially support a shaft with an axis of rotation of the exhaust gas turbocharger, and wherein a first outflow gap and a second outflow gap, respectively, are formed between the first radial bearing and a radially extending first supporting wall of the turbocharger, which faces a turbine wheel of the exhaust gas turbocharger for axially supporting the first radial bearing, and the second radial bearing and a radially extending second supporting wall of the turbocharger, which faces a compressor wheel of the exhaust gas turbocharger for axially supporting the second radial bearing. The first outflow gap and/or the second outflow gap is configured inclined or curved relative to the axis of rotation for the axial and simultaneously radial support and/or for the backup of the radial support.

A bearing device for an exhaust gas turbocharger, comprising a first radial bearing and a second radial bearing, the radial bearings radially support a shaft with an axis of rotation of the exhaust gas turbocharger, and wherein a first outflow gap and a second outflow gap, respectively, are formed between the first radial bearing and a radially extending first supporting wall of the turbocharger, which faces a turbine wheel of the exhaust gas turbocharger for axially supporting the first radial bearing, and the second radial bearing and a radially extending second supporting wall of the turbocharger, which faces a compressor wheel of the exhaust gas turbocharger for axially supporting the second radial bearing. The first outflow gap and/or the second outflow gap is configured inclined or curved relative to the axis of rotation for the axial and simultaneously radial support and/or for the backup of the radial support.

A bottoming cycle power system includes an expander disposed on a crankshaft. The expander being operable to receive a flow of exhaust gas from a combustion process and to rotate the crankshaft as the exhaust gas passes through. An absorption chiller system has a generator section having a first heat exchanger to receive the flow of exhaust gas from the expander and to remove heat from the exhaust gas after the exhaust gas has passed through the expander. An evaporator section has a second heat exchanger to receive the flow of exhaust gas from the generator section and to remove heat from the exhaust gas after the exhaust gas has passed through the generator section. A compressor is disposed on the crankshaft and connected to the flow of exhaust gas. The compressor is operable to compress the exhaust gas after the exhaust gas has passed through the second heat exchanger.

A system includes an air source, an internal combustion engine, a first turbocharger, a second turbocharger, and a third turbocharger. The first turbocharger includes a first turbine and a first compressor, the second turbocharger includes a second turbine and a second compressor, and the third turbocharger includes a third turbine and a third compressor. The third compressor is fluidly coupled to the air source and is fluidly coupled to one of the first compressor and the second compressor. The first compressor is fluidly coupled upstream of the second compressor, and the second compressor is fluidly coupled upstream of the third turbine. The third turbine is fluidly coupled upstream of the internal combustion engine.

A method of joining parts of the wastegate assembly, and a wastegate assembly includes an arm defining a hole. The wastegate assembly also includes a shaft. The shaft includes a first end disposed inside the hole of the arm. The shaft includes an outer surface defining a groove disposed inside the hole of the arm. The arm and the first end of the shaft are welded together to form a joint having a joint root region disposed adjacent to the groove.

A turbocharger includes a compressor, a turbine and a rotating assembly driven by exhaust gas. The rotating assembly has a turbine wheel disposed inside the turbine and a compressor wheel disposed inside the compressor. The turbocharger further includes the wastegate assembly described above, and the wastegate assembly defines an opening configured to selectively redirect at least a portion of the exhaust gas to bypass the turbine wheel.

A method of joining parts of the wastegate assembly, and a wastegate assembly includes an arm defining a hole. The wastegate assembly also includes a shaft. The shaft includes a first end disposed inside the hole of the arm. The shaft includes an outer surface defining a groove disposed inside the hole of the arm. The arm and the first end of the shaft are welded together to form a joint having a joint root region disposed adjacent to the groove.

A turbocharger includes a compressor, a turbine and a rotating assembly driven by exhaust gas. The rotating assembly has a turbine wheel disposed inside the turbine and a compressor wheel disposed inside the compressor. The turbocharger further includes the wastegate assembly described above, and the wastegate assembly defines an opening configured to selectively redirect at least a portion of the exhaust gas to bypass the turbine wheel.

A method for manufacturing a turbine wheel comprising casting the turbine wheel from an austenitic nickel-chromium-based superalloy, subjecting the cast turbine wheel to hot isostatic pressing and then subjecting a surface of the hot isostatically pressed turbine wheel to plastic deformation, wherein said hot isostatic pressing is effected at a pressure of 98 to 200 MPa and a temperature of 1160 to 1220 C. for a time period of 225 to 300 minutes. There is further described a hot isostatically pressed cast turbine wheel manufactured from an austenitic nickel-chromium-based superalloy, the turbine wheel having a plastically deformed surface; and a turbocharger incorporating such a turbine wheel.

A method for manufacturing a turbine wheel comprising casting the turbine wheel from an austenitic nickel-chromium-based superalloy, subjecting the cast turbine wheel to hot isostatic pressing and then subjecting a surface of the hot isostatically pressed turbine wheel to plastic deformation, wherein said hot isostatic pressing is effected at a pressure of 98 to 200 MPa and a temperature of 1160 to 1220 C. for a time period of 225 to 300 minutes. There is further described a hot isostatically pressed cast turbine wheel manufactured from an austenitic nickel-chromium-based superalloy, the turbine wheel having a plastically deformed surface; and a turbocharger incorporating such a turbine wheel.

A method for operating an engine system is provided, the method may include varying a compression ratio of a cylinder by selectively releasing combustion charge from the cylinder through a cylinder bleed valve of a cylinder head, the cylinder bleed valve coupled to a bleed manifold with a turbine-generator, and varying combustion charge flow through a turbine-generator bypass conduit bypassing the turbine-generator based on engine operating conditions. In this way, the compression ratio may be varied by selectively bleeding combustion charge from the cylinder based on engine operating conditions to promote better engine performance. Additionally, the combustion charge bleed from the cylinder can routed around a turbine-generator to increase combustion efficiency during certain operating conditions, such as during start-up, to further improve engine performance.

A method for operating an engine system is provided, the method may include varying a compression ratio of a cylinder by selectively releasing combustion charge from the cylinder through a cylinder bleed valve of a cylinder head, the cylinder bleed valve coupled to a bleed manifold with a turbine-generator, and varying combustion charge flow through a turbine-generator bypass conduit bypassing the turbine-generator based on engine operating conditions. In this way, the compression ratio may be varied by selectively bleeding combustion charge from the cylinder based on engine operating conditions to promote better engine performance. Additionally, the combustion charge bleed from the cylinder can routed around a turbine-generator to increase combustion efficiency during certain operating conditions, such as during start-up, to further improve engine performance.