Abstract: The present disclosure relates to a simplified roots-type blower having an improved sound signature. The roots-type blower includes a rotor bore housing having a molded, one-piece polymeric construction. The rotor bore housing defines a first rotor bore and a second rotor bore. The rotor bore housing also defines a first bearing pocket corresponding to the first rotor bore and a bearing pocket corresponding to the second rotor bore axis. The rotor bore housing further defining a timing gear chamber.

Abstract: A supercharger rotor with reduced rotational inertia may result in increased performance of a supercharger. The rotor may include composite material and may be extrusion molded, injection molded, or otherwise molded or laid-up. In certain embodiments, the rotor may include a core with a central portion and one or more radially extending portions. The core may be extruded or formed of stacked sheets. A molded portion of the rotor, including one or more lobes, may be molded over a corresponding one of the radially extending portions. In other embodiments, a main portion of the rotor includes one or more lobes but no central hole nor a corresponding shaft extending between ends of the main portion. Instead, stub shafts are attached to the ends of the main portion. The increased performance may include decreased noise, decreased cost, increased reliability and/or durability, increased thermal efficiency, an increased power-to-weight ratio, etc.

Abstract: A rotor assembly having a plurality of rotor plates mounted to a shaft, and methods of construction for a rotor assembly are disclosed. Each rotor plate in the assembly may be provided with a central opening extending between the first and second sides through which the shaft extends. In one aspect, the rotor plates are provided with a plurality of lobes extending away from the central opening, wherein each of the lobes has a lobe opening extending through the thickness of the plates. In one embodiment, the rotor plates are rotationally stacked to form a helical rotor.

Abstract: A rotor assembly having a plurality of rotor plates mounted to a shaft, and methods of construction for a rotor assembly are disclosed. Each rotor plate in the assembly may be provided with a central opening extending between the first and second sides through which the shaft extends. In one aspect, the rotor plates are provided with a plurality of lobes extending away from the central opening, wherein each of the lobes has a lobe opening extending through the thickness of the plates. In one embodiment, the rotor plates are rotationally stacked to form a helical rotor.

Abstract: An optimized mechanical expander or fluid expansion device with a delayed opening timing is disclosed. In the optimized design, rotors in the expander alternatingly rotate sequentially through an intake position in which the transport volume is open to the housing inlet, a closed position in which the transport volume is closed to the housing outlet, and a discharge position in which the transport volume is open to the housing outlet. During rotation, a first opening forms between the housing and each rotor. After further rotation, a second opening is formed that is located between the first opening and a back end of the rotor. In one aspect, the mechanical expander has an opening profile including an initial opening phase in which the opening between the rotor and outlet forms at a lesser rate than during a subsequent secondary opening phase.

Abstract: An exhaust gas energy recovery system includes a power plant and a volumetric fluid expander. The power plant has an exhaust gas outlet for conveying an exhaust gas stream at a first pressure. The volumetric fluid expander includes a housing and an output shaft. The housing has an inlet and an outlet, and the housing inlet is in fluid communication with the exhaust gas outlet. The volumetric fluid expander generates useful work at the output shaft by expanding the exhaust gas stream to a second pressure lower than the first pressure generally without reducing the volume of the exhaust stream as the exhaust stream moves from the housing inlet to the outlet.

Abstract: The present teachings generally include an energy recovery device with heat dissipation mechanisms. The energy recovery device can include a main housing, rotors disposed in the main housing, rotor shafts associated with the rotors, and a sub-housing. The sub-housing can have an engaging surface that faces and is spaced apart from the first receiving surface of the main housing with a first gap when the first sub-housing is attached to the main housing.

Abstract: An engine assembly is provided that includes an engine throttle and a supercharger placed in series with one another in air flow to the engine. The throttle and supercharger can be controlled so that throttling losses are selectively distributed across the throttle and/or the supercharger. Throttling losses placed across the supercharger can create torque that can be converted to stored energy.

Abstract: A multi-stage expansion device having bypass capabilities and a variable speed drive is disclosed. In one example, the multi-stage expansion device has a housing within which a first stage, a second stage, and a third stage are housed. The housing may also be configured with internal working fluid passageways to direct a working fluid from the first stage to the second stage and/or from the second stage to the third stage. Each of the stages may include a pair of non-contacting rotors that are mechanically connected to each other and to a power output device such that energy extracted from the working fluid is converted to mechanical work at the output device. In one example, a bypass line is provided to bypass working fluid around the first stage and a bypass line is provided to bypass working fluid around the second stage.

Abstract: A volumetric expander (20) configured to transfer a working fluid and generate useful work includes a housing. The housing includes an inlet port (24) configured to admit relatively high-pressure working fluid and an outlet port (26) configured to discharge to a relatively low-pressure working fluid. The expander also includes first and second twisted meshed rotors (30,32) rotatably disposed in the housing and configured to exp/and the relatively high-pressure working fluid into the relatively low-pressure working fluid. Each rotor has a plurality of lobes, and when one lobe of the first rotor is leading with respect to the inlet port, one lobe of the second rotor is trailing with respect to the inlet port. The expander additionally includes an output shaft (38) rotated by the relatively high-pressure working fluid as the fluid undergoes expansion. A system for generating work using the expander in a Rankine cycle is also disclosed.

Abstract: The present teachings generally include a rotor assembly having a plurality of rotor sheets or layers mounted to a shaft, and methods of construction for a rotor assembly. Each rotor sheet or layer in the assembly may be provided with a central opening extending between the first and second sides through which the shaft extends. In one aspect, the rotor sheets or layers can be provided with a plurality of lobes extending away from the central opening, wherein each of the lobes can have a lobe opening extending through the thickness of the sheets or layers. In one example, the rotor sheets or layers can be rotationally stacked to form a helical rotor. In one example, the rotor sheets are formed from a pre-cured composite material and are bonded together with an adhesive.

Abstract: A rotor assembly having a plurality of rotor plates mounted to a shaft, and methods of construction for a rotor assembly are disclosed. Each rotor plate in the assembly may be provided with a central opening extending between the first and second sides through which the shaft extends. In one aspect, the rotor plates are provided with a plurality of lobes extending away from the central opening, wherein each of the lobes has a lobe opening extending through the thickness of the plates. In one embodiment, the rotor plates are rotationally stacked to form a helical rotor.

Abstract: A volumetric expander (20) configured to transfer a working fluid and generate useful work includes a housing. The housing includes an inlet port (24) configured to admit relatively high-pressure working fluid and an outlet port (26) configured to discharge to a relatively low-pressure working fluid. The expander also includes first and second twisted meshed rotors (30,32) rotatably disposed in the housing and configured to exp/and the relatively high-pressure working fluid into the relatively low-pressure working fluid. Each rotor has a plurality of lobes, and when one lobe of the first rotor is leading with respect to the inlet port, one lobe of the second rotor is trailing with respect to the inlet port. The expander additionally includes an output shaft (38) rotated by the relatively high-pressure working fluid as the fluid undergoes expansion. A system for generating work using the expander in a Rankine cycle is also disclosed.

Abstract: An engine assembly is provided that includes an engine throttle and a supercharger placed in series with one another in air flow to the engine. The throttle and supercharger can be controlled so that throttling losses are selectively distributed across the throttle and/or the supercharger. Throttling losses placed across the supercharger can create torque that can be converted to stored energy.

Abstract: A supercharger (12) with two separate sets of rotors (22, 24) arranged in parallel with one another is provided in an engine assembly. Both sets of rotors are used to boost air flow during high engine air flow conditions, and only one of the sets of rotors is operable to transfer torque generated by the throttling loss pressure drop as stored energy in a load device during low air flow conditions. The captured throttling losses may be electrical energy stored in a battery via a motor/generator such as during vehicle cruising.

Abstract: A rotor assembly having a plurality of rotor plates mounted to a shaft, and methods of construction for a rotor assembly are disclosed. Each rotor plate in the assembly may be provided with a central opening extending between the first and second sides through which the shaft extends. In one aspect, the rotor plates are provided with a plurality of lobes extending away from the central opening, wherein each of the lobes has a lobe opening extending through the thickness of the plates. In one embodiment, the rotor plates are rotationally stacked to form a helical rotor.

Abstract: A volumetric assembly includes: a roots-type supercharger device; a roots-type expander device; a first duct extending from the supercharger fluid inlet, the first duct supplying fluid to the roots-type supercharger device; and a second duct extending from the expander fluid outlet, the second duct directing fluid away from the roots-type expander device, wherein the first duct is positioned adjacent to the second duct, and wherein the first duct defines a first aperture and the second duct defines a second aperture, the first and second apertures being generally aligned; and a flexible membrane positioned between the first and second ducts in the first and second apertures, the flexible membrane sealing the first duct from the second duct, and the flexible membrane flexing as fluid flows within the first and second ducts to attenuate noise associated with the fluid flows.

Abstract: A Rankine cycle system including a Rankine cycle working circuit and a lubrication circuit is disclosed. The lubrication circuit and the Rankine cycle working circuit include a shared segment including a mixture of Rankine cycle working fluid from the Rankine cycle working circuit and lubricant from the lubrication circuit. A separator receives the mixture of Rankine cycle working fluid and lubricant from the shared segment and separates the Rankine cycle working fluid from the lubricant. The separated Rankine cycle working fluid is directed along the Rankine cycle working circuit from the separator to the heating zone and the separated lubricant is directed along the lubrication circuit from the separator to a mechanical expander. The working fluid and lubricant are recombined after passing separately through the expander and are then introduced to the condensing zone.

Abstract: A multi-stage expansion device is disclosed. In one embodiment, the multi-stage expansion device has a housing within which a first stage, a second stage, and a third stage are housed. The housing may also be configured with internal working fluid passageways to direct a working fluid from the first stage to the second stage and/or from the second stage to the third stage. Each of the stages may include a pair of non-contacting rotors that are mechanically connected to each other and to a power output device such that energy extracted from the working fluid is converted to mechanical work at the output device. In one embodiment, a step up gear arrangement is provided between the rotors of the first and second stages. A step up gear arrangement may also be provided between the rotors of the second and third stage.