Abstract: The invention relates to a side-channel machine having a housing (4a), located in the housing (4a) a side-channel (28) for guiding a gas, and at least one gas inlet opening (34) which is formed in the housing (4a) and is fluidically connected to the side-channel (28). Furthermore, the side-channel machine has at least one gas inlet pipe (29a) which connects to the at least one gas inlet opening (34), The side-channel machine further comprises at least one gas outlet opening (33) and at least one gas outlet pipe (31a) which connects to the at least one gas outlet opening (33). Furthermore, the side-channel machine has an impeller that can be made to rotate in the housing (4a), with impeller blades, which bound impeller cells arranged in the side-channel (28), for delivering the gas in the impeller cells from the at least one gas inlet opening (34) to the at least one gas outlet opening (33).

Abstract: Side-channel compressor (1) for a fuel cell system (37) for conveying and/or compressing a gas, in particular hydrogen, having a housing (3), wherein the housing (3) has a housing upper part (7) and a housing lower part (8), having a compressor chamber (30) which is situated in the housing (3) and which has at least one encircling side channel (19), having a compressor wheel (2) which is situated in the housing (3) and which is disposed so as to be rotatable about a rotation axis (4), wherein the compressor wheel (2) on the circumference thereof has blades (5) which are disposed in the region of the compressor chamber (30), and having a gas inlet opening (14) and a gas outlet opening (16) which are in each case configured on the housing (3) and which by way of the compressor chamber (30), in particular the at least one side channel (19), are fluidically connected to one another.

Abstract: An evaporated fuel processing device includes a fuel tank, a canister, an atmospheric passage, a vapor passage, an intake pipe, a purge passage, a purge pump, and a flow rate control valve. The evaporated fuel is desorbed utilizing only negative pressure in the intake pipe when sufficient negative pressure is generated in the intake pipe. The purge pump is driven to desorb the evaporated from the canister when sufficient negative pressure is not generated in the intake pipe. The purge pump and the flow rate control valve may be provided in the purge passage. The purge pump is a vortex pump through which the gas can flow even when drive is stopped. The minimum cross-sectional area of the internal space of the flow passage of the purge pump is equal to or larger than the minimum cross-sectional area of the internal space of the other parts of the purge passage.

Abstract: An adaptive cycle gas turbine engine is disclosed having a number of features. A fan arrangement is provided having counter-rotating fan stages, one fan stage is operable to be clutched and decoupled from the other stage. A high pressure compressor bypass is also provided. A clutch is provided to at least partially drive an intermediate pressure compressor with a high pressure turbine when the high pressure compressor is bypassed. A partial bypass of the high pressure turbine may be provided.

Abstract: A fluid working apparatus (130) includes a housing structure (130) with an inlet (132), an outlet (133), an outer housing member (134) defining a tubular portion with an inner surface and an inner housing member (138) within the outer housing member (130) and having an outer surface spaced from the inner surface such that a working flow chamber (141) is defined between the radially inner most portions of the outer and inner surfaces and a return chamber (140) is defined between the radially outer most portions of the outer and inner surfaces. A working assembly is positioned in the housing with a rotor (114) thereof rotatably supported in the housing structure (130) and extending into the working flow chamber (141). At least one return assembly (140, 142) is positioned within the tubular portion and configured to return fluid flow from an outlet side to an inlet side of the working assembly (141). A method of defining a re-circulating working fluid apparatus is also provided.

Abstract: A side channel compressor for compressing a gas comprises a housing (3), a side channel (30), located in the housing (3) and having a cross-sectional area (A), for compressing a gas, a gas inlet opening (31) formed in the housing (3), the gas inlet opening (31) being in flow connection with the side channel (30) for introducing a gas, a gas outlet opening (32) formed in the housing (3) for discharging the gas to be compressed from the side channel (30), wherein the gas outlet opening (32) is in flow connection with the gas inlet opening (31) via the side channel (30), and an impeller (2) which is mounted for rotation in the housing (3) and comprises impeller blades (1) disposed in the side channel (30), wherein the cross-sectional area (A) of the side channel (30) decreases non-monotonically from the gas inlet opening (31) towards the gas outlet opening (32).

Abstract: Pumping units are known to have an inlet channel, opening out into a pumping channel and tapering from an inlet cross section to an outlet into the pumping channel with an outlet cross-section. The flow is deflected through ninety degrees on entry to the pumping channel which induces strong swirling. The transition from the inlet channel into the pumping channel is not optimal for flow. This effect reduces the efficiency of the pumping unit. The inlet flow into the pumping channel is improved in the pumping unit according to the invention and hence efficiency is improved. According to the invention, the outlet is essentially provided in a first quadrant with relation to the inlet cross section and the tapering of the inlet channel essentially occurs in the other three quadrants. The tapering wall of the inlet channel is formed by a plane-generating shape which goes around from one side of the outlet to the other side of the outlet and is shaped to be increasingly flat relative to a plane of the outlet.

Abstract: The invention relates to a turbine, in particular of an exhaust-gas turbocharger, comprising a turbine rotor which is supported rotatable in a housing, and to which at least one guide vane apparatus forming a radial inlet channel for a medium driving the turbine rotor is allocated, wherein the guide vane apparatus comprises a guide vane mounting ring with a plurality of guide vanes which radially surround the turbine rotor and which are located within the inlet channel, as well as a guide vane cover ring, and wherein the inlet channel is axially bounded by the guide vane mounting ring and the guide vane cover ring, and the guide vane cover ring abuts with a front side facing away from the inlet channel against a support area of the housing. The invention provides that the housing (5) comprises in the support area (15) at least one recess (17) which is open-edged towards the guide vane cover ring (9), and through which the medium can flow.

Abstract: A disc shaped impeller may comprise an upper face and a lower face. Concavities may be repeatedly arranged along a circumferential direction on the upper face and the lower face. Each concavity may include a front surface, a back surface, an inner surface, an outer surface and a bottom surface. Each front surface may include a front-inner area formed between an inner edge of the front surface and a middle portion of the front surface. Each front-inner area may be formed in a convex shape when viewed as a longitudinal cross-section. The longitudinal cross-section is defined as a cross-section through a longitudinal plane disposed so as to be aligned along the circumferential direction.

Abstract: A pump includes a rotatable rotor installed in a motor part and at least one impeller installed in a pump part, capable of being rotated together with the rotor in unison. The rotor and the impeller are accommodated in a casing, and the impeller has an inlet at an inner periphery thereof and an outlet at an outer periphery thereof. A housing is arranged in both sides of an axial direction of the impeller and has an outer peripheral part coupled to the rotor at a rear side portion thereof, and the outer peripheral part is projected outwards further than a gap between an outer peripheral surface of the rotor and an inner peripheral surface of the casing in which the rotor is rotatably accommodated.

Abstract: A vapor lock in a fuel pump can be prevented by reducing the formation of vapor within the fuel. A first group of concavities may be formed in an inner circumferential region of an intake side face of an impeller, and a second group of concavities may be formed concentrically in a region outside of the first group of concavities. A third group of concavities that communicates with the second group of concavities may be formed in a discharge side face of the impeller. The impeller is housed within a casing. A first groove that faces the first group of concavities and a second groove that faces the second group of concavities may be formed in the face of the casing that faces the intake side face of the impeller. A third groove that faces the third group of concavities may be formed in the face of the casing that faces the discharge side face of the impeller.

Abstract: The machine comprises an impeller, provided with blades connected to a central body of the impeller; the impeller is closed in a casing which defines an annular conduit, in which the blades rotate, which annular conduit exhibits an intake mouth and a delivery mouth and further exhibits a first tract which goes from the intake mouth to the delivery mouth, a free space is provided in the first tract between the rotating blades and the internal walls of the annular conduit. The conformation of the radial section of the annular conduit can be modified by application of interchangeable elements to parts of the machine which define the free space.

Abstract: A blower comprising: a vane wheel including a pair of grooves, and blades extending in a radial direction of the vane wheel in each groove, and a casing including stationary flow paths facing to the grooves respectively so that the gas urged in the grooves is capable of flowing in a circumferential direction in the stationary flow paths, a guide flow path extending in the axial directions to fluidly communicate with both of the stationary flow paths to enable the gas to flow from one of the stationary flow paths to the other one of the stationary flow paths, an inlet port for introducing the gas into the one of the stationary flow paths facing to the one of the grooves and an outlet port for discharging the gas out of the other one of the stationary flow paths facing to the other one of the grooves.

Abstract: A pump having a housing with a torus and a stripper region. The stripper region has a housing groove formed on the surface of the stripper region. The housing groove has a surface forming a length, width and depth of the groove. The pump also has a cover connectable to the housing. The cover extends over the housing groove formed on the surface of the stripper region. An impeller has a plurality of vanes that extend radially outward from an impeller frame, wherein the impeller is rotatably positioned between the housing. The cover and the plurality of vanes are positioned in operable relation to said housing groove.

Abstract: A fuel pump includes a housing, and a motor. An impeller has first and second impeller flow channels having a plurality of vanes positioned therein. The impeller defines a flow passageway extending through the impeller. A cover is attached to the housing and defines a cover flow channel. The cover flow channel receives fuel from an inlet formed in the cover. A first portion of the cover flow channel is aligned with the first impeller flow channel and a second portion of the cover flow channel is aligned with the second impeller flow channel. The cover flow channel extends around the cover more than 360 degrees. A body is positioned within the housing and defines an impeller chamber, sized to receive the impeller, and an outlet passageway is positioned to fluidically connect to the flow passageway of the impeller to receive higher pressure fuel for delivery to the engine.

Abstract: Fuel pump (10) may comprise a casing (18) and a substantially disc-shaped impeller (20) which is rotatably disposed within the casing (18). A first group of concavities (21a) may be formed in a lower face of the impeller (20). A second group of concavities (20a) may be formed in an upper face of the impeller (20). A first groove (30) may be formed in the inner face of the casing (18) opposite the upper face of the impeller (20). The first groove (30) is formed in a region opposite the first group of concavities (21a) and extending from an upstream end to a downstream end. A second groove (24) may be formed in the inner face of the casing opposite the lower face of the impeller (20). The second groove (24) is formed in a region opposite the second group of concavities (20a) and extending from an upstream end to a downstream end.

Abstract: A blower comprising: a vane wheel including a pair of grooves, and blades extending in a radial direction of the vane wheel in each groove, and a casing including stationary flow paths facing to the grooves respectively so that the gas urged in the grooves is capable of flowing in a circumferential direction in the stationary flow paths, a guide flow path extending in the axial directions to fluidly communicate with both of the stationary flow paths to enable the gas to flow from one of the stationary flow paths to the other one of the stationary flow paths, an inlet port for introducing the gas into the one of the stationary flow paths facing to the one of the grooves and an outlet port for discharging the gas out of the other one of the stationary flow paths facing to the other one of the grooves.

Abstract: A turbine fuel pump includes an impeller having blades, each including a linear blade portion extending linearly in the radial direction of the impeller and a curved blade portion extending circularly curvedly from the head of the linear blade portion to the forward side of the impeller as viewed in the direction of rotation of the impeller. The linear blade portion has a length of (? to ?)×H, where H is an overall length of the impeller.

Abstract: A pump includes a pumping unit including therein an impeller for sucking and discharging a liquid; and a pump case accommodating therein the pumping unit and provided with an inlet for sucking the liquid into the pump and an outlet for discharging the liquid out of the pump. The impeller has an inlet mouth portion of a cylindrical shape that projects towards the pump case, and the pump case has a case inlet portion and an annular recess portion which the inlet mouth portion of the impeller is movably inserted in and is formed at the vicinity of the case inlet portion.

Abstract: A fuel pump is provided with a casing and a substantially disk-shaped impeller that can rotate within the casing. A group of concavities is formed in each surface of the impeller. The concavities forming the group are arranged in concentric circles with respect to the rotation axis of the impeller. A first groove is formed in a first inner surface of the casing and extends from an upstream end to a downstream end in an area that faces one group of concavities. A second groove is formed in a second inner surface of the casing and extends from an upstream end to a downstream end in an area that faces the other group of concavities. A seal portion is formed in at least one of the first and second inner surfaces of the casing and formed by one layer or a plurality of layers of thin film.

Abstract: A secondary air system providing a regeneration air pump wherein the vanes of the impeller are tapered from a point along the length of the vane to the root of the vane inside the air pump. The tapered vanes create desirable flow characteristics. The tapered vanes create a non-linear flow versus pressure characteristic. Thus, the tapered vanes in combination with a divider that extends circumferentially around the impeller and through the vanes causes the flow to increase. This non-linear characteristic created by the tapered vanes allows the secondary air system to maintain suitable operation at lower flow and pressure levels. Due to the tapered feature on the impeller, a dead head pressure is obtained at a lower pressure. The impeller arrangement also provides overall pump efficiency improvements.

Abstract: A vacuum side channel compressor (10) comprises a pump stator (14) and a pump rotor (12), which surround a side channel (31,32,33,34). An axial bearing (22) is provided for mounting the pump rotor (12). A sealing gap (40) is formed next to the side channel between the pump stator (14) and the pump rotor (12), part of which forms a conical ring whose imaginary cone apex (50) lies in the vicinity of the axial bearing (22).

Abstract: A fuel pump is provided having improved efficiency by lowering the wet circle index of the pump while maintaining robust axial clearances to meet the demands of an automotive application. One embodiment includes a fuel pump for pressurizing fuel for delivery to an engine of a motor vehicle. The fuel pump generally comprises a housing, a motor, a single sided impeller, a cover and a body. The provision of a single sided impeller greatly reduces the wet circle index and improves the pump efficiency. The cover, impeller, and body are structured to axially balance the impeller which is free floating on the shaft of the motor.

Abstract: A device (1), for evacuating a chamber to pressures in the high vacuum range includes a suction-side vacuum pump (2) and an atmospheric-pressure-side vacuum pump (3). The suction-side vacuum pump (2) is a mechanical kinetic vacuum pump with a rotor (11) and a stator (10). The stator (10) has a rotationally-symmetrical inner surface which matches the outer rotor geometry. The rotor (11) in the mechanical kinetic vacuum pump (2) is provided with a structure (13) carrying out the gas pumping. Said gas pumping structure comprises webs (14), the angle and width of which decrease from the suction side to the pressure side. The gas throughflow is improved. The outer diameter of the rotor (11) and the inner diameter of the stator (10) of the suctnion-side pump decrease from the suction side to the pressure side.

Abstract: A rotary fuel pump employs pressure balancing features on the non-vaned side of the impeller to provide localized application of fluid forces so that the impeller is more precisely balanced within the pumping chamber. A generally disc-shaped impeller body has an impeller with a body-side surface and a cover-side surface. The cover-side surface defines an impeller flow channel extending circumferentially around the impeller. The impeller includes a plurality of vanes positioned at least partially within the impeller flow channel. The body-side surface has a plurality of discontinuous undercut regions each coaxially aligned with at least a portion of the impeller flow channel. The impeller has a plurality of apertures wherein each aperture connects the impeller flow channel with a respective undercut region, whereby pressure forces against the impeller from the fuel are substantially balanced in the axial direction.

Abstract: A fuel pump to be disposed in a fuel tank to supply pressurized fuel to an internal combustion engine includes a motor section, a pump section including an impeller driven by the motor section and a cylindrical pump housing having a pump passage extending along the outer periphery of the impeller so as to pressurize fuel, a suction filter and a feed passage member disposed around the inlet port of the pump passage. The feed passage member has a smooth feed passage connecting the pump passage and the suction filter. The feed passage tapers off toward an inlet port of the pump passage that opens at a peripheral portion of the pump housing.

Abstract: In a pumping arrangement for a chamber, a regenerative pumping mechanism comprises a rotor and a stator having an annular channel within which rotor blades rotate to urge fluid along the channel. The channel has a stripper, a channel inlet positioned adjacent one end of the stripper and through which fluid from the chamber enters the channel, and a channel outlet positioned adjacent the other end of the stripper and through which pressurised fluid leaves the channel. The stator further comprises a fluid bypass in the form of a bore having an inlet and an outlet on either side of the stripper. A valve allows fluid entering the channel to selectively diverted through the bore to the channel outlet. This can allow the performance of the pump to be varied without changing the speed of rotation of the rotor, and thus allow the pressure in the chamber to be accurately controlled.

Abstract: A molecular drag vacuum pump configured for pumping a gas stream from an inlet to an outlet, the pump including a high-speed spinning disk or rotor disposed within a housing. A passageway is formed inside the housing adjacent the disk, and gas comes in contact with surfaces of the spinning disk in successive stages, conformable wipers being disposed adjacent the spinning disk to direct the gas stream to the successive stages. The disk can be powered by an integrated motor, comprising permanent magnets associated with the disk and cooperating coils associated with the housing. The wipers can include parallel ridges on a contacting face to facilitate creation of a conformable fit with the rotor. Seal rings may be disposed against the disk between gas passageways to reduce leakage therebetween, and the pump may include regenerative pumping pockets to help prevent backflow. The housing may have a modular configuration to allow two or more pump modules to be connected and operate in series.

Abstract: A fuel pump prevents pressurized fuel from being pulled into a clearance between an outer circumference face of an impeller and an inner circumference face of a pump case, thereby allowing the delivery of the pressurized fuel from a pump body side to a pump cover side through through-holes of the impeller. Since a clearance C2 between an impeller outer circumference face 16p and a pump cover inner circumference face 39c is made extremely small, the pressurized fuel is caused to pass via through-holes 16c that communicate between an upper and an lower side of an impeller 16. By this means, it is difficult for the pressurized fuel to enter the clearance C2, and it is possible to prevent the decrease in pump efficiency caused by pressure at the impeller outer circumference face 16p and the vicinity thereof.

Abstract: A fuel pump is provided having improved efficiency by lowering the wet circle index of the pump while maintaining robust axial clearances to meet the demands of an automotive application. One embodiment includes a fuel pump for pressurizing fuel for delivery to an engine of a motor vehicle. The fuel pump generally comprises a housing, a motor, a single sided impeller, a cover and a body. The provision of a single sided impeller greatly reduces the wet circle index and improves the pump efficiency. The cover, impeller, and body are structured to axially balance the impeller which is free floating on the shaft of the motor.

Abstract: A turbine fuel pump includes an impeller having blades, each including a linear blade portion extending linearly in the radial direction of the impeller and a curved blade portion extending circularly curvedly from the head of the linear blade portion to the forward side of the impeller as viewed in the direction of rotation of the impeller. The linear blade portion has a length of (? to ?)×H, where H is an overall length of the impeller.

Abstract: A pressure pulse generator for a downhole drilling tool is provided. The pressure pulse generator includes a stator with an orifice through which a stream of fluid passes, and a rotor intended to rotate opposite the stator to allow the flow of more or less liquid exiting the orifice of the stator. The rotor is equipped with an orifice, and the two orifices present a communicating area for the passage of the stream of fluid. The rotor is capable of passing fluid therethrough. A turbine with blades rotatable in response to fluid flow through the rotor may also be provided. The turbine is operatively connected to the rotor via a drive shaft. The fluid flow through the rotor may be used to rotate the turbine and provide power usable in the downhole tool.

Abstract: The invention relates to a feed pump (2) that is configured as a side-channel pump with a plurality of identically designed feed chambers (6, 7) with outlet channels (22, 23) that are disposed opposite one another, thereby eliminating the radial forces acting upon the impeller (4) of the feed pump (2). The feed pump (2) according to the invention is especially wear-free and has a very high degree of efficiency.

Abstract: An impeller pump (1) for a fluid includes a rotary impeller (5) and a pump housing (3, 4). The pump housing defines a first main flow channel (3a) and a second main flow channel (4a). A first inlet channel (3b) and a second inlet channel (4b) also are defined in the pump housing. The first inlet channel communicates with one end of the first main flow channel and the second inlet channel communicates with one end of the second main flow channel, so that the fluid is drawn into a first pump chamber (1b) and the second pump chamber (1c) via the first inlet channel and the second inlet channel, respectively.

Abstract: A single stage, dual channel turbine fuel pump for use in a vehicle fuel delivery system, generally including a lower casing, an upper casing, an impeller and a motor. Both the lower and upper casings have a pair of concentric, annular grooves formed on their surfaces, where the two lower annular grooves are in fluid communication with a fuel passage inlet and the two upper annular grooves are in fluid communication with a fuel passage outlet. Rotation of the impeller causes a portion of the incoming fuel to be diverted into an inner lower groove and another portion into an outer lower groove. Once in the lower grooves, the fuel communicates with other parts of the pumping chamber such that it fills the upper grooves as well. Generally independent, helical fuel flow patterns are formed which cause the fuel to become pressurized as it flows from the inlet to the outlet.

Abstract: An impeller pump has a pump casing (6) that defines a pump chamber. The pump chamber includes a first chamber (21) and a second chamber (22). An impeller (10) is rotatably disposed within the pump chamber. The impeller has a first groove group and a second groove group on opposite surfaces. The first groove group and the second groove group oppose to the first chamber and the second chamber, respectively, so that a fluid is draw into and discharged from the first and second chambers as the impeller rotates. The flows of the fluid discharged from the first and second chambers are converged at a converging channel (26). Pulsations of the fluid discharged from the fist and second chambers are canceled each other when the flows converge at the converging channel.

Abstract: A turbine pump includes a casing having an inlet, an outlet and front and rear arc-shaped pump passages and an impeller. The impeller has plural impeller partitions respectively disposed between every two of the blades thereby forming impeller grooves at front and rear sides of the partitions and an outer ring at the peripheral edge of the blades. Each impeller groove, each of pump passage and the outer ring form a space for circulating fuel. The outside diameter of the impeller is smaller than the pump passages so that the impeller does not contact the pump passages.

Abstract: A rotary machine includes a helical flow compressor/turbine and a permanent magnet motor/generator including a housing with a stator positioned therein. A shaft is rotatably supported within the housing. A permanent magnet rotor is mounted on a shaft and operatively associated with the stator. An impeller is mounted on the shaft and includes an impeller disk with a plurality of impeller blades extending therefrom. The housing includes a generally horseshoe-shaped fluid flow stator channel with an inlet at a first end and an outlet at a second end. The fluid in the generally horseshoe-shaped fluid flow stator channel proceeds from the inlet to the outlet while following a generally helical flow path with multiple passes through the impeller blades. The impeller disk has a plurality of axially-oriented vent holes formed therethrough to minimize a pressure differential across the impeller, thereby minimizing thrust loads applied to the impeller.

Abstract: A regenerative fluid dynamic machine, typically a blower or compressor, includes an impeller (1) with fixedly attached blades (6) which may be radial or curved in a general convex fashion facing forward in the direction of turning. The impeller is enclosed in a housing which, together with the shaped profile of the rotor flank/s defines a toroidal passage (7) between inlet an outlet ports, fluid flow in said passage/s following a path which forms a spiral centred generally within the cross section of the passage, said housing may be provided with slideable side walls that are made to contact and expand the width of said toroidal passage to change the operation of the compressor so as to meet the requirements of fluid delivery or pressure. A preferred option is also proposed that will achieve a superior result through variations to the circumference span of the inlet passage.

Abstract: A fuel pump for a vehicle includes a pump section having a flow channel and a rotatable impeller cooperating with said flow channel to pump fuel therethrough. The fuel pump also includes a motor section disposed adjacent the pump section and having a motor to rotate the impeller. The fuel pump further includes an outlet section disposed adjacent the motor section to allow pumped fuel to exit the fuel pump. The impeller includes a plurality of blades that are generally V shaped and have thinned edges.

Abstract: An impeller has a plurality of blades at an outer periphery thereof. Each of the adjacent blades define a groove space, and a partition wall is provided in the groove space. The partition wall is disposed at a center area of the groove space in an axial direction of the impeller for partitioning the groove space from a root of the blade. The blade inclines backwardly in the rotating direction at the root side thereof, and inclines frontwardly in the rotating direction at a radial outer end side thereof. A front face is inwardly concaved from both axial ends, and warps from the root to the radial outer end of the blade to form the concave such that the concave gradually becomes small from the root to the radial outer end.

Abstract: A casing includes a C-shaped casing side pump groove along blades of an impeller. A casing cover also includes a casing cover side pump groove facing the casing side pump groove. The casing side pump groove and the casing cover side pump groove form a pump fluid passage. A gap is provided between an outer surface of the pump grooves and the impeller. Depth, and outer and inner diameters of a pump groove starts to gradually change from a fuel upstream side of a fuel outlet. The depth of the pump groove gradually decreases, the outer diameter of the pump groove gradually decreases to approach an outer diameter of the impeller, and the inner diameter of the pump groove gradually increases to approach the outer diameter of the impeller. The pump groove ends at a downstream side of the fuel outlet.

Abstract: In a feed pump designed as a side-passage pump and having a driven impeller rotating in a housing a liquid to be fed is supplied radially from the inside to guide blades arranged in the impeller. For this purpose, the impeller has a groove adjoining the guide blades. As a result, Feed pump has an especially high efficiency.

Abstract: A fuel pump has a motor with a shaft extending therefrom and an impeller fitted thereon for pumping fuel from a fuel tank to an internal combustion engine. A pumping chamber, which encases the impeller, is comprised of a cover channel and a bottom channel formed in a pump cover and a pump bottom, respectively. The impeller has a plurality of radially extending vanes on an outer circumference separated by partitions of shorter radial length. The partitions are comprised of substantially quarter-circle shaped arcuate portions extending from the outer circumference of the impeller to a diverging portion, preferably to a substantially flat top with rounded corners. Fluid active vane grooves thus formed circumferentially between the vanes and axially between the partitions which reduce fuel vortices angular acceleration within the pumping chamber thus increasing pump efficiency.