A forced induction device (100) includes: a rotor (1) which includes a turbine side shaft portion (11), a compressor side shaft portion (12), and a connection shaft portion (13) connecting these to each other; a turbine side bearing (5) which supports the turbine side shaft portion (11); and a compressor side bearing (6) which supports the compressor side shaft portion (12). A rigidity of the connection shaft portion (13) is lower than that of the turbine side shaft portion (11) and the compressor side shaft portion (12) so that a node in a mode shape at each critical speed involving with an operating rotational speed region of the rotor (1) is located between the turbine side bearing (5) and the compressor side bearing (6).

A system includes an engine defining a water jacket fluidly coupled to a heat exchanger. An exhaust manifold defines an exhaust manifold cooling passage. A pump is fluidly coupled to the water jacket, and to each of the heat exchanger and the exhaust manifold cooling passage. An engine cooling circuit includes the water jacket, the heat exchanger, and the pump. An exhaust cooling circuit is selectively fluidly coupled to the engine cooling circuit. The exhaust cooling circuit includes the water jacket, the exhaust manifold cooling passage, and the pump. A control valve includes an inlet fluidly coupled to a first portion of the water jacket. A first outlet is fluidly coupled to a second portion of the water jacket. A second outlet is fluidly coupled to the exhaust cooling circuit. The control valve is structured to selectively control flow of coolant fluid through the second outlet.

A turbocharger includes a variable nozzle unit, a bearing housing, a circular heat shield plate located between a turbine impeller and the bearing housing, and a water chamber formed in the bearing housing. The heat shield plate is fixed by being pressed against the variable nozzle unit by a disc spring and is radially aligned by being fitted into the bearing housing by a fitting portion. The heat shield plate includes a fitting surface formed in the fitting portion and an inner peripheral heat shield portion projecting radially inward from the fitting surface and located with an axial gap between the inner peripheral heat shield portion and the bearing housing. At least a part of the water chamber exists at the same radial position as a radial position of the fitting portion.

A turbocharger includes a variable nozzle disposed between a turbine housing and a bearing housing and a spring having an annular shape. The spring is disposed between the variable nozzle and the bearing housing, and is configured to generate a biasing force that biases the variable nozzle away from the bearing housing to widen a spacing between the variable nozzle and the bearing housing in a rotation axis direction. The spring includes an outer peripheral portion that applies the biasing force to the variable nozzle and an inner peripheral portion that comes into contact with the bearing housing. The outer peripheral portion of the spring is located further away from the turbine housing than the inner peripheral portion of the spring in the rotation axis direction.

A centrifugal compressor includes: a housing accommodating an impeller; a diffuser flow path formed radially outside the impeller in the housing; and a scroll flow path formed in the housing and connected to the diffuser flow path from a radially-outer side, the scroll flow path extending in a rotational axis direction and a rotational direction of the impeller with respect to the diffuser flow path, the scroll flow path including a radially-inner end located at the radially-innermost position, and the radially-inner end being spaced apart from the diffuser flow path with respect to a middle point of the maximum flow path width of the scroll flow path in the rotational axis direction.

A variable capacity turbocharger includes a housing, a turbine impeller at least partially located in the housing, a scroll flow path located in the housing and encircling the turbine impeller, a first nozzle ring and a second nozzle ring facing each other in the housing, a nozzle flow path located between the first nozzle ring and the second nozzle ring and fluidly coupling the scroll flow path to the turbine impeller, a gap formed between the first nozzle ring and the housing, and a bearing hole located in the first nozzle ring and including an opening adjacent to the gap. The gap is located on an opposite side of the first nozzle ring to the nozzle flow path. Additionally, the gap is connected to the scroll flow path.

High cycle fatigue (HCF) in a turbine wheel of a sector-divided dual volute turbocharger, particularly a turbocharger where the tongue-to-blade gap is as small as from 1-3% of the wheel diameter, is reduced, and energy extraction is optimized, using a turbine wheel with (blade stiffness/backwall stiffness×100) between 41 and 44.

High cycle fatigue (HCF) in a turbine wheel of a sector-divided dual volute turbocharger, particularly a turbocharger where the tongue-to-blade gap is as small as from 1-3% of the wheel diameter, is reduced, and energy extraction is optimized, using a turbine wheel with (blade stiffness/backwall stiffness×100) between 41 and 44.

A power delivery system includes a first inverter, a second inverter, and a turbocharger assist device. The first inverter is electrically connected to a primary bus and configured to receive electric current from an alternator via the primary bus to supply the electric current to a first load. The alternator generates the electric current based on mechanical energy received from an engine. The second inverter is electrically connected to a secondary bus discrete from the primary bus. The turbocharger assist device is mechanically connected to a turbocharger operably coupled to the engine. The turbocharger assist device is electrically connected to the secondary bus and configured to generate electric current based on rotation of a rotor of the turbocharger. The second inverter is configured to receive the electric current generated by the turbocharger assist device via the secondary bus to supply the electric current to a second load.

A power delivery system includes a first inverter, a second inverter, and a turbocharger assist device. The first inverter is electrically connected to a primary bus and configured to receive electric current from an alternator via the primary bus to supply the electric current to a first load. The alternator generates the electric current based on mechanical energy received from an engine. The second inverter is electrically connected to a secondary bus discrete from the primary bus. The turbocharger assist device is mechanically connected to a turbocharger operably coupled to the engine. The turbocharger assist device is electrically connected to the secondary bus and configured to generate electric current based on rotation of a rotor of the turbocharger. The second inverter is configured to receive the electric current generated by the turbocharger assist device via the secondary bus to supply the electric current to a second load.