Abstract: An exemplary compressor for a turbocharger includes a compressor wheel that includes first and second compressor faces oriented back-to-back and a bore for mounting the compressor wheel to a shaft along a rotational axis of the compressor wheel; and a compressor housing that includes a first air inlet oriented to pass inlet air in an axial direction along the rotational axis to the first compressor face, a second air inlet positioned a distance radially from the rotational axis and oriented to pass inlet air in an axial direction parallel to the rotational axis and radially toward the rotational axis to the second compressor face, and a single volute that receives compressed air from the first and second compressor faces.

Abstract: Exemplary turbine blade outer edges, exemplary vane inner edges, exemplary systems and exemplary methods are disclosed that help to reduce noise in variable geometry turbines and optionally other turbines wherein a turbine blade interacts with an object. Other exemplary turbine-related technologies are also disclosed.

Abstract: Turbochargers of this invention comprise a turbine housing and a turbine wheel rotatably disposed therein. A center housing is connected to the turbine housing, and a compressor housing is attached to the center housing. A compressor is rotatably disposed within the compressor housing, and comprises two impellers placed in back-to-back orientation. A movable member is disposed within the compressor housing to downstream of the compressor to control the flow of air within the compressor housing. The position of the movable member can be operated to control the amount of pressurized air that is produced by one of the compressor impellers to provide enhanced compressor operating efficiency throughout the operating range and mass flow requirements of the engine.

Abstract: Exemplary turbine blade outer edges, exemplary vane inner edges, exemplary systems and exemplary methods are disclosed that help to reduce noise in variable geometry turbines and optionally other turbines wherein a turbine blade interacts with an object. Other exemplary turbine-related technologies are also disclosed.

Abstract: A two-stage radial compressor having a ported second-stage shroud, forming a passive surge control system. Thus, some proportion of the fluid is allowed to flow between the second-stage of the compressor in the vicinity of the impeller blade tips, through a port in the shroud into an upstream portion of the compressor flow path that leads into the second-stage impeller inlet. The fluid is allowed to flow in either direction, depending on the pressure difference existing between the two locations. Surge margin at higher pressure ratios is significantly increased by the ported second-stage shroud.

Abstract: Methods and apparatus for mixing fluids are provided. The devices and methods operate without moving parts, and generate well-mixed fluids over a broad dynamic range of flow rates. Preferred embodiments include junction-type mixers, bundled mixers, and co-axial mixers. The devices and methods are optimized to produce rapid, accurate gradients to improve associated system throughput and reproducibility.

Abstract: A turbocharger includes a compressor wheel having back-to-back impellers (i.e., a forward-facing impeller and a rearward-facing impeller) mounted on the same shaft. The two impellers are independently supplied with inlet air via separate inlet ducts and discharge pressurized air to a common volute. The inlet duct for the rearward-facing impeller comprises a generally axially extending tubular conduit having an upstream end and a downstream end, the tubular conduit being bifurcated at the downstream end into a pair of separate duct branches that divide an air stream flowing through the tubular conduit into a pair of separate air streams. The duct branches direct the air streams radially inwardly and then re-join the streams and turn the air to an axial direction into the second impeller.

Abstract: Microfluidic systems including a principal microfluidic conduit (24), an adjacent dead volume (1) and a drain conduit (70) which mitigates the adverse effects of the dead volume on the operation of the system.

Abstract: An electrochemical cell for processing a sample fluid, has a body with a flow path, the flow path having an inlet and an outlet; a reference electrode in fluid communication with the flow path; a counter electrode in fluid communication with the flow path; a porous working electrode in fluid communication with the flow path, the working electrode having a working electrode material; an electrical connection for the working electrode in electrical contact with the working electrode; and a working electrode section in the flow path. The working electrode is positioned inside the working electrode section. The working electrode section has a volume of from about 1 pL to about 1 ?L.

Abstract: A microfluidic detection device provides reduced dispersion of axial concentration gradients in a flowing sample. The microfluidic detection device includes a cell body and a flow path through the cell body. The flow path has an inlet segment, an outlet segment, and a central segment, which forms a detection cell. The central segment is located between and at an angle with both the inlet segment and the outlet segment. The central segment has a first junction with the inlet segment and a second junction with the outlet segment. The cell body contains two arms that can transmit light to and from the detection cell. At least a portion of a first arm is located in the first junction and at least a portion of a second arm is located in the second junction. The portions of the arms located in the junctions are situated so that fluid entering or exiting the central segment of the flow path flows around the outer surface of one of the portions.

Abstract: EGR systems for an internal combustion engine configured to operate using multiple-staged turbochargers, or a pair of single stage turbochargers, to provide exhaust gas recirculation to meet emissions requirements while not affecting engine performance. One or two EGR loops operating at low, intermediate, or high pressures may be employed. EGR exhaust gases may be taken directly from the exhaust manifold, or after the exhaust stream has passed through a turbocharger turbine. EGR exhaust gases may be injected at an intermediate pressure between stages of a multiple stage turbocharger, or alternatively between a low pressure turbocharger compressor and high pressure turbocharger compressor, before being boosted to a pressure high enough to ensure the desired mass flow to the engine and delivered to the intake manifold. Intake air may be pressurized prior to mixing with the EGR exhaust gases.

Abstract: Electroosmotic flow controllers and methods of fluid flow control are described. The invention uses an electroosmotically generated flow component in conjunction with a pressure driven flow component to modulate fluid flow. The devices and methods of the invention may include salt bridges for making electrical connection between a power supply and a channel filled with a porous dielectric material and a fluid. Embodiments including flow controllers and flow splitters are described as is their use in a variety of fluid handling applications.

Abstract: Exemplary methods, devices and/or system for reducing noise produced by a turbine, such as, a turbocharger turbine. An exemplary exhaust conduit employs material to absorb exhaust-borne noise and/or structure-borne noise. Another exemplary exhaust conduit employs features that dampen wall vibration.

Abstract: A multi-stage compressor and associated compressor housing and method are provided. The housing defines an aperture for receiving a compressor wheel for successively compressing a gas in first and second stages. First- and second-stage inlets are fluidly connected to the aperture in generally axial directions, and first- and second-stage volutes extend at least partially annularly therearound so that each volute is configured to receive gas flowing generally radially outward from the compressor wheel. In addition, first and second passages fluidly connect the first-stage volute to the second-stage inlet. Each passage extends from the first-stage volute to a position radially outward of the second-stage volute and therefrom to the second-stage inlet at an axial position opposite the second-stage volute from the first-stage volute.

Abstract: EGR systems for an internal combustion engine configured to operate using multiple-staged turbochargers, or a pair of single stage turbochargers, to provide exhaust gas recirculation to meet emissions requirements while not affecting engine performance. One or two EGR loops operating at low, intermediate, or high pressures may be employed. EGR exhaust gases may be taken directly from the exhaust manifold, or after the exhaust stream has passed through a turbocharger turbine. EGR exhaust gases may be injected at an intermediate pressure between stages of a multiple stage turbocharger, or alternatively between a low pressure turbocharger compressor and high pressure turbocharger compressor, before being boosted to a pressure high enough to ensure the desired mass flow to the engine and delivered to the intake manifold. Intake air may be pressurized prior to mixing with the EGR exhaust gases.

Abstract: A control system of this invention for use with a variable geometry turbocharger is designed to enable turbocharger control based solely on engine speed. The control system takes measured engine speed and sends the same to an engine control unit (ECU) having an actuator position v. engine speed map. The ECU utilizes only the measured engine speed to determine a desired actuator position from the map, and produces a control signal for effecting actuator operation. The control signal generated by the ECU can be converted to an analog signal by pulse width modulation, for example. The control signal is sent to an actuator for placing the actuator into the desired actuator position. The actuator is connected to a variable geometry member in the turbocharger so that operation and placement of the actuator into the desired actuator position thereby places the variable geometry member into a desired position to effect the desired change in turbocharger operation.

Abstract: A method for providing a stop-off material on a workpiece is provided, as is an associated assembly. A maskant is provided on the workpiece such that a first portion of the workpiece is exposed and a second portion of the workpiece is covered by the maskant. The stop-off is then disposed, with the maskant on the workpiece preventing the stop-off from being applied to the second portion of the workpiece. The maskant is removed from the workpiece leaving the stop-off disposed on a select portion of the workpiece. The removal of the maskant can leave the workpiece substantially free of debris. Thereafter, the workpiece can be further processed, e.g., by diffusion bonding, with the stop-off preventing diffusion bonding of part of the workpiece.

Abstract: Methods and apparatus for mixing fluids are provided. The devices and methods operate without moving parts, and generate well-mixed fluids over a broad dynamic range of flow rates. Preferred embodiments include junction-type mixers, bundled mixers, and co-axial mixers. The devices and methods are optimized to produce rapid, accurate gradients to improve associated system throughput and reproducibility.

Abstract: A fuel cell system having a fuel cell, the fuel cell having a membrane-electrode assembly; a fuel reservoir containing a liquid fuel; a conduit coupling the fuel reservoir to the fuel cell; and an electrokinetic fuel pump coupled to the conduit, the electrokinetic fuel pump having a plurality of electrodes; wherein the electrokinetic fuel pump moves fuel from the fuel reservoir through the conduit to the fuel cell; and wherein the electrokinetic fuel pump electrodes do not deleteriously affect the performance of the membrane-electrode assembly.

Abstract: A heat transfer system comprising a primary heat exchanger for receiving heat from a heat source; a secondary heat exchanger for exhausting heat to a heat sink; a conduit connecting the primary heat exchanger and the secondary heat exchanger; and an electrokinetic pump for pumping a heat exchange fluid between the primary heat exchanger and the secondary heat exchanger through the conduit.