Provided is an air charging apparatus driven by a rotating magnetic field and compressing or pressurizing and transferring air. The air charging apparatus includes at least one impeller sucking air and giving kinetic energy to intake air; an impeller case leading external air inhaled by the impeller into the impeller and converting velocity energy of air out of the impeller into air having pressure energy to discharge air; and a rotating body accelerator equipped with the impeller and the impeller case and driving the impeller. Here, the rotating body accelerator drives the impeller by generating a torque by interaction with an intake negative pressure, by generating a torque by interaction with the intake negative pressure and using supplied power, or by generating a torque using supplied power.

According to an aspect of the present disclosure, a seal structure includes a rotary shaft that is provided inside a housing, a metal-made surrounding portion of the housing that surrounds the rotary shaft in a radial direction of the rotary shaft, and a resin-made seal member that faces an inner circumferential surface of the surrounding portion and rotates together with the rotary shaft.

A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between an open position and a closed position in the air inlet. The inlet-adjustment mechanism includes a plurality of blades disposed about the air inlet and collectively circumscribing an orifice, the blades being movable inwardly through a slot in the air inlet wall so as to adjust the size of the orifice. Compressor performance is optimized through selection of inlet-adjustment mechanism parameters including the minimum orifice area when closed AR.sub.c, spacing distance L between the minimum-area point and the compressor wheel leading edge, blade shape, and orifice shape.

A system for real-time modeling includes a compressor designed to operate at a compressor speed, a compressor flow rate, and a compressor pressure ratio. The system also includes a memory designed to store an operating condition matrix that plots multiple compressor pressure ratios to each of a plurality of compressor speeds, and a related operating state matrix that plots multiple compressor flow rates to each of the plurality of compressor speeds. The system also includes a compressor controller to determine a target compressor speed and a target compressor pressure ratio, and to identify a target location in the operating condition matrix based on the target compressor speed and the target compressor pressure ratio. The compressor controller also determines a target compressor flow rate by interpolating values in the operating state matrix based on the target location, and to control the compressor based on the target compressor flow rate.

A system for real-time modeling includes a compressor designed to operate at a compressor speed, a compressor flow rate, and a compressor pressure ratio. The system also includes a memory designed to store an operating condition matrix that plots multiple compressor pressure ratios to each of a plurality of compressor speeds, and a related operating state matrix that plots multiple compressor flow rates to each of the plurality of compressor speeds. The system also includes a compressor controller to determine a target compressor speed and a target compressor pressure ratio, and to identify a target location in the operating condition matrix based on the target compressor speed and the target compressor pressure ratio. The compressor controller also determines a target compressor flow rate by interpolating values in the operating state matrix based on the target location, and to control the compressor based on the target compressor flow rate.

An oil film damper of a bearing structure is located between facing surfaces of two bearings. The oil film damper includes two protrusions protruding inward in a radial direction from an inner circumferential surface of a main body portion, an oil guiding passage penetrating through from the protrusion to an outer circumferential surface of the main body portion and guiding a lubricating oil from the outer circumference of the main body portion to the bearing, an inclined surface provided on a side opposite to the adjacent surface adjacent to the bearing in the protrusion and having an inner diameter gradually increasing as the diameter is separate from the adjacent surface in the rotation axis direction of the shaft, and an oil discharge hole provided between the two protrusions of the main body portion and discharging the lubricating oil to an outside from an inside of the main body portion.

An oil film damper of a bearing structure is located between facing surfaces of two bearings. The oil film damper includes two protrusions protruding inward in a radial direction from an inner circumferential surface of a main body portion, an oil guiding passage penetrating through from the protrusion to an outer circumferential surface of the main body portion and guiding a lubricating oil from the outer circumference of the main body portion to the bearing, an inclined surface provided on a side opposite to the adjacent surface adjacent to the bearing in the protrusion and having an inner diameter gradually increasing as the diameter is separate from the adjacent surface in the rotation axis direction of the shaft, and an oil discharge hole provided between the two protrusions of the main body portion and discharging the lubricating oil to an outside from an inside of the main body portion.

An exhaust gas turbocharger may include a turbine housing and a turbine arranged in the turbine housing. The turbine housing may include at least two exhaust gas channels and a partition separating the at least two exhaust gas channels from one another. A wastegate valve may be arranged such that the at least two exhaust gas channels are connectable to a bypass duct bypassing the turbine. The wastegate valve may include a valve body and a valve seat interacting with the valve body. The wastegate valve may be configured such that at least one of a ram supercharging operation and a pulse supercharging operation is activated depending on a degree of opening of the wastegate valve.

An exhaust gas turbocharger may include a turbine housing and a turbine arranged in the turbine housing. The turbine housing may include at least two exhaust gas channels and a partition separating the at least two exhaust gas channels from one another. A wastegate valve may be arranged such that the at least two exhaust gas channels are connectable to a bypass duct bypassing the turbine. The wastegate valve may include a valve body and a valve seat interacting with the valve body. The wastegate valve may be configured such that at least one of a ram supercharging operation and a pulse supercharging operation is activated depending on a degree of opening of the wastegate valve.

A turbocharger system can include a housing that includes a through bore, a plurality of lubricant bores, a plurality of lubricant bore to through bore openings and a recessed compressor-side surface that defines in part a passage that fluidly couples at least two of the lubricant bores; a rolling element bearing unit disposed at least in part in the through bore of the housing; and, a plate that covers at least a portion of the recessed compressor-side surface of the housing.