Abstract: An exemplary fuel spray bar system can include a conduit, which is pivotally attached to an engine frame and configured to deliver fuel from a fuel line to an engine flow path. The system further includes a drive mechanism, which is configured to move the conduit between a stowed position and a deployed position.

Abstract: Devices and methods for reducing noise of a blower reduce and/or substantially block the exchange of gas within the blower housing from an area of a generally high-velocity flow of gas to an area of a comparatively lower-velocity flow of gas, for example near the outlet of the blower housing.

Abstract: An automated system for dampening pulsation of a medium, wherein the system comprises a pressure pulsation dampener, a transducer, and a control unit for instructing a motor to move the choke plate depending on signals sent from the transducer. The pressure pulsation dampener has a housing, a choke plate, a shaft, an indicator plate, a stop pin and a removable fastener for engaging at least one of the plurality of indicator openings and securing to a portion of the outlet half housing.

Abstract: Blades forming a turbofan included in an indoor unit each have, in a blade outer-circumferential surface of the blade and near a blade rear-edge portion, a plurality of rear-edge horizontal grooves extending horizontally (in a plane perpendicular to a center of rotation) with predetermined lengths L2 reaching the blade rear-edge portion. The rear-edge horizontal grooves are each a combination of a groove recessed portion provided with a predetermined depth in the blade outer-circumferential surface and a groove wrapping portion continuous with the groove recessed portion and provided at the terminal end of the blade rear-edge portion. The rear-edge horizontal grooves are provided in a region extending upward from the main plate defined by a distance H1 and in a region extending downward from the shroud defined by a distance H2.

Abstract: A damper arrangement (10) has a first Helmholtz damper (11) connected in series to a second Helmholtz damper (12). The resonance frequency of the first Helmholtz damper (11) and the resonance frequency of the second Helmholtz damper (12) are shifted from one another in an amount producing a synergic damping effect.

Abstract: A muffler for a vehicle is provided, including: a muffler housing having a first housing body and a second housing body that are divided in two parts and form an internal space with an inlet opening and an outlet opening when combined; and an internal structure inserted and forced into the internal space of the muffler housing to be detachable from the muffler housing, and allowing an exhaust gas discharged from an engine to flow into the internal space and to be discharged out of the muffler housing through a predetermined path.

Abstract: An embodiment includes a transparent sash mounted integral to the perforated doors on racks which hold computer servers typically installed in data centers. The racks are arrayed in rows forming cold aisles and hot aisles. Cooled air introduced into the cold aisle flows through the racks and cools the servers, and subsequently is removed from the hot aisle. Embodiment sashes slide vertically and extend above the tops of the racks and form a sealing relationship with the data center ceiling and adjacent sashes, thereby preventing wasteful mixing and recirculation of cooled and heated air over the tops of the racks. Embodiments are raised and lowered manually or automatically. The controls for the movement of the sashes are tied to the building automation and fire alarm systems and the sashes are lowered automatically upon activation of the data center fire suppression system, thereby complying with code requirements and avoiding interference with the fire sprinkler and suppression systems.

Abstract: A muffling device has a muffling piece that is placed in an airflow path and muffles sound caused by airflow, and a drive unit that performs one of rotation and movement of the muffling piece.

Abstract: A container data center includes a movable container, two server systems having a cold aisle and two hot aisles, two fan apparatuses, an exchanger, and an air intake apparatus. The air intake apparatus includes a number of air intake elements each defining an air channel. The fan apparatuses are operable to transfer hot airflow in the hot aisles into the heat exchanger, and then the heat exchanger transforms the hot airflow into cold airflow and transfers the cold airflow into the cold aisle through the air intake apparatus. The air intake elements are connected together and cover the cold aisle. The air intake elements of the air intake apparatus are arranged in a “V” shape along an orientation toward the airflow of the cold aisle.

Abstract: An exhaust-gas muffler (1) has a housing (2) through which at least one sleeve (11) projects. At one end, the sleeve (11) has an attachment opening (10) and at the opposite-lying end has an access opening (14). To avoid a contamination of the sleeve (11) during operation, a plug (15, 25, 35, 40, 45, 55) of a pressed metal wire is arranged in the access opening (14).

Abstract: A flow diffuser for vehicles of the type having an engine and an exhaust pipe generally includes a substantially tubular body having an outer surface and a first end configured for attachment to an exhaust pipe. The flow diffuser further includes a diffusion portion including at least one channel having a root end located near the outer surface, an exit port, and a channel axis extending between the root end and the exit port, the channel increasing in flow area along the channel axis to reduce exhaust gas velocity.

Abstract: An adjustable Helmholtz resonator assembly is provided having an active state and an inactive state. In the active state the Helmholtz resonator assembly is operable to attenuate pressure pulsations within air passing therethrough. In the inactive state the Helmholtz resonator assembly does not attenuate pressure pulsations within air passing therethrough. The Helmholtz resonator assembly is preferably configured to be mounted within an intake system of an internal combustion engine.

Abstract: A sound-baffling arrangement for use in conjunction with an air-handling unit. One or more sound baffle columns are mounted for rolling or sliding movement within the interior of the air handling unit housing. Each baffle column may be selectively moved between a use position proximate to the fan assemblies, and a non-use position more distal from the fan assemblies. The movable sound baffles permit the air-handling unit to be fabricated to fit within a smaller housing, and thus to have a smaller, more economical footprint.

Abstract: The invention uses tubes for the reduction of radiated duct noise. The tubes may be used to attenuate narrow band noise by diverting a portion of the acoustic energy through the tubes back into the duct. Upon reintroducing the diverted flow out of phase with the primary flow, acoustic cancellation is achieved. The frequency at which this occurs is dependent on the difference in the path lengths through the tubes and the separation distance—the distance separating the inlet and outlet of the tube. This invention can be used over varying frequency ranges by using an arrangement of flexible, constant length tubes. The effective frequency range is tailored by varying the separation distance and also allows the varying the angular arrangement of the tubes for more effective attenuation of spinning modes having varying propagation angle.

Abstract: A muffler outlet part for a muffler to be used in exhaust systems of motorcycles has at least one main body disposed transversely to an outflow direction of exhaust gas and having a center axis, the main body having a centrical first outlet opening disposed concentrically relative to the center axis for the outflow of exhaust gas from an outlet chamber of the muffler, and at least one second outlet opening disposed eccentrically relative to the center axis for the outflow of exhaust gas from an expansion chamber of the muffler, said expansion chamber enclosing the outlet chamber. It further has at least one closing member that is swivel-mounted about the center axis for an at least partial closing of the at least one second outlet opening, and at least one adjustment element for swiveling of the closing member via an adjustment means, which cooperates in a torque-transmitting manner with the at least one adjustment element.

Abstract: A powertrain control system is provided that includes an engine having multiple cylinders. A controller selectively activates the cylinders to provide a cylinder combination having a desired power displacement. In one example powertrain control system, the controller selectively activates the cylinders between a V-8 and V-4 mode. An exhaust system having a valve and an electrical actuator selectively electrically actuates the valve in response to the controller between multiple positions. The electrical actuator moves the valve from an open position in V-8 mode to a partially closed position in V-4 mode to increase back pressure and reduce NVH issues in V-4 mode. A muffler includes a housing having an exhaust passage. The valve is supported by the housing and arranged in the exhaust passage. The valve is moveable between multiple positions for tuning the muffler. The electrical actuator is supported by the housing to actuate the valve between the multiple positions.

Abstract: A control system (10) controls a variable acoustical damping device (20) disposed in a sound producing channel (5) of a vehicle engine (1). The control system includes a controller (12) and a selection device (14). The controller is coupled to the variable acoustical damping device and stores a plurality of control patterns (A. B) for different levels of acoustical damping of the acoustical damping device. The selection device outputs a selection signal to the controller so that the controller controls the variable acoustical damping device based on one of the control patterns corresponding to the selection signal.

Abstract: The present invention provides a resonator for attenuating acoustic vibration from an air intake passage. The resonator includes a neck, a resonator chamber, a piston-type member, and an actuator. The neck is attached between the air passage and the resonator chamber. The neck has two overlapping portions allowing the neck to extend within the resonator chamber. The piston-type member is located within the resonator chamber and is translated by the actuator to change the volume of the resonator and the neck length. By changing the volume and neck length of the resonator, the frequency attenuated by the resonator can be adjusted.

Abstract: The present invention relates to a silencer easily cleanable inside. This silencer comprises a casing cylinder and a segment member housed in the casing cylinder to constitute a sound reducing means. The silencer further comprises a segment member fastening means for fastening the segment member to the casing cylinder, a gas inlet-side lid plate with a punched hole, which closes an opening at one end of the casing cylinder, and a gas outlet-side lid plate with a punched hole, which closes an opening at the other end of the casing cylinder. At least either one of the gas inlet-side lid plate or the gas outlet-side lid plate is adapted to be detachable from the casing cylinder.

Abstract: An acoustic filter is provided with a single flow chamber for exposure of a flexible rubber layer to liquid undergoing flow through the flow chamber with noise producing acoustic energy therein. The flexible rubber layer is supported on a cylindrical drum with slanted holes therein through which the exposure to the liquid in the flow chamber is effected. An axially sectioned drum with dimensionally different diameters, radial thicknesses and slanted holes therein is positioned over the rubber layer within an outer casing to establish a plurality of gas-filled cavities of different axial lengths and separated from each other along the axial length of the liquid flow chamber which is connected at its opposite axial ends by pipe sections to a piping system from which the liquid within the flow chamber is derived.

Abstract: A silencer or sound attenuator for gas flows that makes use of noise baffles is provided with a lateral movement mechanism which allows the baffles to be moved perpendicular to the direction of the gas flow within the silencer. A silencer provided with the lateral movement mechanism allows personnel to have access to the interior of the silencer so that the baffles can be cleaned without having to remove the baffles from the silencer. The lateral movement mechanism may include a roller assembly installed at the top of each baffle which operates within a corresponding track that is provided to the inner upper surface of the housing. The lateral movement mechanism may also include a caster assembly, which is provided to the bottom of each baffle to aid in lateral movement.

Abstract: An in-line resonator for an air induction system of an internal combustion engine is provided. The system includes a resonator housing, an upstream duct, a downstream duct, a conduit, a partition, and a sleeve. The conduit extends through the resonator housing connecting the upstream duct and the downstream duct. The partition is moveable within the resonator housing and divides the housing into an upstream chamber and a downstream chamber. The downstream chamber, the conduit, and the downstream sleeve cooperate to form a first Helmholtz resonator that is in fluid communication with the downstream duct. The upstream chamber, the conduit, and the upstream sleeve cooperate to form a second Helmholtz resonator that is in fluid communication with the upstream duct. Further, a means is provided to axially move the partition to vary the volume of the chambers concurrently with the length and/or area of the passages.

Abstract: An assembly useful in reducing aircraft engine noise such as turbofan engine noise (730) comprises: (i) at least one tube “H-Q” having an inlet end (738), an outlet end (740) and a central tube portion therebetween; and (ii) at least one actuator operatively interconnected to at least one tube, wherein the actuator is capable of causing dynamic response by the tube. The assembly of this invention may be used in a method for reducing noise, the method comprising: (a) providing means for generating non-uniform noise energy about an inner surface and within a disclosure having at least an inlet; (b) providing an assembly for reducing noise comprising; (i) at least one having an inlet end, an outlet end and a central tube portion therebetween, and (ii) at least one actuator operatively interconnected to at least one tube, wherein the actuator is capable of causing dynamic response by the tube; and (c) directing at least a portion of the non-uniform noise into the assembly.

Abstract: An exhaust muffler system for use on a motorcycle or four-wheeled vehicle provides for operation in either of two modes, a regular configuration that provides a high degree of noise reduction, or a racing specification that provides for a freer-flowing exhaust. Without changing the main body of the muffler, an operator can choose between a quieter, public road setting or a louder, high performance setting. The muffler is provided with two interchangeable spark arresters, and a main body having multiple expansion chambers therein, defined by bulkheads. When a regular spark arrester is installed, exhaust gas passes through one bulkhead three times, greatly reducing the noise produced. With the spark arrester removed, the exhaust gas passes straight through to the open air, enhancing performance. A seal is provided between the bulkheads and the spark arrester, which provides for extension or retraction in the lengthwise direction of the tail pipe.

Abstract: An exhaust processor comprises a Helmholtz resonance chamber with a variable tuning throat. The tuning frequency of the exhaust processor changes as the outlet opening from the variable tuning throat into the Helmholtz resonance chamber changes.

Abstract: A sound producing vehicle exhaust system comprises a housing positionable over an exterior end of a vehicle tailpipe. A turbine has at least one support plate. The support plate is rotatable about a central axis of rotation with the housing and has a plurality of angular blades with interior ends coupled to the support plate for rotation there with. At least one facing disk is positioned within the housing adjacent to the turbine. A central axis is provided through the facing disk and support plate. At least one bearing pin is provided. The bearing pin rotatably couples the support plate to the facing disk. A plurality of apertures extend through the facing disk. In this manner exhaust gasses from a tailpipe will pass through the blades and create a turbine-like sound.

Abstract: A sound level adjustable muffler has a pop-up mechanism working in parallel pairs used for lifting the tabletop part of a piece of furniture has a pair of cantilever arms joined together by an upper oblong member and a lower oblong member, both said upper oblong member and lower oblong member being parallel relative to each other and each being rotationally attached to opposite ends of said pair of cantilever arms.

Abstract: An exhaust processor comprises a Helmholtz resonance chamber with a variable tuning throat. The tuning frequency of the exhaust processor changes as the outlet opening from the variable tuning throat into the Helmholtz resonance chamber changes.

Abstract: A number of embodiments of acoustical devices for improving either or both the intake and exhaust sounds emanated from an internal combustion engine. This is achieved by employing acoustical devices which are configured so as to discharge the desired sound waves to the atmosphere rather than by attempting to dampen the undesired sound waves generated in the system.

Abstract: An apparatus for damping acoustic vibrations in a combustor as well as a corresponding combustor arrangement with the apparatus. The apparatus includes a Helmholtz resonator (4) that can be connected via a connecting channel (2) with a combustor (1). The Helmholtz resonator (4) contains a hollow body (6) the volume of which can be changed by adding or draining a fluid via a supply line (5), or is located adjacent to such a hollow body in such a way that the resonance volume (3) of the Helmholtz resonator (4) is changed when the volume of the hollow body (6) is changed. This apparatus makes it possible to adjust the resonance frequency of a Helmholtz resonator arranged inside a pressure container in accordance with the respective current operating point of the combustor to be damped, without having to pass movable components through the pressure container.

Abstract: The present invention provides a sound attenuator for pneumatic exhaust that includes a body having an open end and an inner cavity defined by an inner wall, an inlet port provided in the body adapted to establish fluid communication between a source of pneumatic exhaust and the inner cavity, a cap releasably connected to the body to cover the open end, at least one exit port in fluid communication with the inner cavity, a plurality of baffles arranged within the inner cavity so as to define a series of sequential closed chambers between the inlet port and the exit port, and a deflector proximal to the exit port, the deflector redirecting the flow of pneumatic exhaust at least 90° and cooperating with an exterior surface of the body to define an expansion zone. Each of the baffles has a periphery in contact with the inner wall and is adapted to flex under a predetermined pneumatic pressure load to permit the pneumatic exhaust to flow between the periphery and the inner wall of the body.

Abstract: In-line exhaust systems comprise an exhaust pipe, and a sound-attenuating baffle in the exhaust pipe. The baffle has one or more baffle plates extending across the gas flow channel, at least one at an oblique angle. Each plate has an array of apertures therethrough. The plates are joined to each other, preferably in edge-to-edge relationship, preferably forming included angles with each other and forming preferably different, oblique angles to the longitudinal axis. In preferred embodiments, plate aperture area increases, plate-to-plate, along the direction of advance of gases in the exhaust system. A backwash valve can lie over one of the baffle plates. The exhaust system can include a water jacket, and optionally an outer sound attenuation chamber. The baffle is preferably 36 or less inches long, the exhaust system reducing noise by at least 3 decibels.

Abstract: A submuffler for a vehicle muffler system which comprises a housing, a pressure-reducing conduit disposed within said housing, said pressure-reducing conduit containing a plurality of apertures disposed on the surface thereof, an eddy-generating member disposed within the pressure-reducing conduit along a substantial length thereof, and pipe means connected to an inlet side and an exit side of the housing for introducing exhaust gas thereto and exiting exhaust gas therefrom.

Abstract: A resonator provided for air system that includes a body defining a passageway. A wall is disposed within the chamber and the wall and the chamber are movable relative to one another to define a length and a volume of the cavity. The length and the volume of the cavity define a noise attenuating frequency. By moving the wall and chamber relative to one another the noise attenuating frequency may be changed as the frequency changes during the engine operation. The drive mechanism moves the wall in the chamber relative to one another to change the noise attenuating frequency. The chamber may be a branched type resonator or an inline type resonator. Accordingly, the above described invention provides a resonator that may be adjusted during engine operation to attenuate noise over a variety frequencies.

Abstract: A sound adjustable tail pipe structure includes an adjuster secured in a rear section of a tail pipe which defines a first oblong slot. The adjuster includes a tube having a first end provided with a first positioning base and a second end provided with a second positioning base, and an adjusting base rotatably mounted in the second positioning base. The first positioning base defines a first through hole connecting to the tube and has a wall defining a plurality of first guide holes. The second positioning base defines a second through hole connecting to the tube and has a wall defining a plurality of second guide holes, and a peripheral wall defining a second oblong slot. The adjusting base defines a third through hole connecting to the second through hole and has a wall defining a plurality of third guide holes aligning with each of the second guide holes, and a peripheral wall defining a screw hole.

Abstract: A turbine exhaust structure is provided for a vehicle which includes an exhaust tail pipe having an inner wall defining a screw hole. The turbine exhaust structure includes a turbine exhaust device secured in the inner wall of the exhaust tail pipe, and a bolt co-operating with a nut for securing the turbine exhaust device in the inner wall of the exhaust tail pipe through the screw hole. The turbine exhaust device includes a housing secured in the inner wall of the exhaust tail pipe, a wheel disk secured in the housing, a plurality of catch pieces mounted in the wheel disk, an axle base secured in a central portion of the wheel disk, an axle rod rotatably mounted in the axle base of the wheel disk and having a first end provided with a first vane wheel and a second end provided with a second vane wheel, and two bearings mounted between the axle base and the axle rod.

Abstract: A secondary air injection system for reducing the hydrocarbon emissions of an internal combustion engine that is provided with an air pump supplying air to the exhaust manifold of the engine through a check valve assembly and an elastomeric hose characterized in that a baffle in the shape of a helix is located internally within the hose so as to cause the exhaust pressure waves from the engine and passing beyond the check valve assembly to impinge upon the solid compound surface of the baffle and be divided and diffused as they progress along spiraling paths so as to prevent objectionable noises being generated in the hose by the pressure waves.

Abstract: An exhaust pipe extension having movable fan blades mounted on a center axle which blades and part of the axle extend into an opened vehicle exhaust pipe. The other end of the same axle is fixed connected to a rotatable end decorative visual spinner within a hollow housing. To provide for individuality the visual spinner can take on a variety of different sizes and shapes. The spinner rotates in unison with the propelled fan blades which blades are driven by the vehicle's exhaust gases. Appropriate easily detachable mounts are used to fix the housing and its axle and the fan blade members to the vehicle's exhaust pipe to provide for an attractive add-on accessory.

Abstract: A free rotor is mounted to spin freely in a conduit network that is acoustically coupled to a noise source through a working fluid that flows through the conduit network. The free rotor muffles the acoustic perturbations travelling through the conduit network, thus effectively muffling the noise source. The network has at least one extent of conduit and within the extent of conduit. The free rotor is typically mounted with its axis of rotation parallel to the direction of flow of the working fluid. Additional free muffling rotors may be provided, either counter rotating or rotating in the same direction. If adjacent free rotors rotate in the same direction, it is beneficial to provide a stationary blade row between them. The multiple free rotors may be mounted on the same spindle, or mounted on independent spindles.

Abstract: An inlet or exhaust line for a reciprocating machine attenuates the sound level of the machine while being simple and economical to produce. A sensor measures the instantaneous flow rate of gases passing through the line while a restriction device variably restricts the cross-section of the line as a function of the instantaneous flow rate measured by the sensor. Material for absorbing acoustic energy covers the internal wall of the line.

Abstract: An auto-adjusting damper assembly for an air muffler, such assembly including a spring loaded damper plate located above an outlet hole for transferring some of the energy of incoming air into a mechanical movement of such damper.

Abstract: A variable displacement wobble plate type refrigerant compressor includes a plurality of axially reciprocating pistons. A drive shaft rotates the wobble plate and thereby reciprocates the pistons within their respective compression chambers. Gaseous refrigerant is admitted to each compression chamber through a suction valve and discharged from each compression chamber through a discharge valve. Each discharge valve opens to a common discharge cavity. A hub is rotatable supported about a fixed axis within the discharged cavity, or downstream of the discharge cavity. A plurality of blades pivotally extend from the hub. A compression spring is disposed inside the hub for biasing the blades toward a flat condition.

Abstract: When there is relative movement, at a speed above a critical value, between the trailing edge of a body, such as a hydrofoil or aerofoil section, and a fluid, the fluid flow tends to form a pattern of discrete swirling vortices. Vortex shedding at each side of the trailing edge alternately can cause resonance or "singing" of the section. The effect of this phenomenon is reduced by forming contiguous triangular flat-faced notches in the major surfaces of the section, adjacent the trailing edge, but leaving the profile of the leading edge substantially undistrubed. The notches in one major surface are preferably staggered relative to those in the other major surface.

Abstract: A fluid friction controller that includes an outer member having a first friction control surface and an inner member having a second friction control surface. The control surfaces coact to define an elongated orifice that diverges from its entrance toward its exit. The length of the orifice is related to the angle of divergence so that the flow of a fluid passing therethrough remains attached to the control surfaces and the dynamic pressure in the flow does not exceed the static pressure at any point along the length of the orifice.

Abstract: A charge air system for an internal combustion engine includes a compressor wheel which is rotated to draw ambient air into a housing, compress the air, and to force the air through a discharge conduit into the the intake manifold of an internal combustion engine. The silencers may be placed in the inlet conduit or the outlet conduit to attenuate pressure fluctuations in the conduits, which are a source of significant noise.

Abstract: A muffler responsive to exhaust flow rate is provided for an internal combustion engine. The muffler includes a body having a variable restrictor located downstream from an inlet port and upstream from an outlet port of the muffler. The variable restrictor includes a valving element with an operative position which varies as a function of engine exhaust flow rate to occlude exhaust gas flow. The variable restrictor is formed with a solid wall disposed about the valving element to define a constricting annular passageway having a cross section that varies with distance from the inlet port and from the outlet port. The passageway cross section for some mufflers will increase in a direction proceeding from the inlet port toward the outlet port, and will decrease proceeding in that same direction in other mufflers, depending upon the type of internal combustion engine employed.

Abstract: A spoiler is located on the damper blade of a damper assembly such that it serves to divert the flow from the hinge area to avoid air separation. Further, the spoiler does not define the most restricted portion of the flow path and thereby has a minimal effect on the flow resistance.

Abstract: A silencing system for exhaust gases from internal combustion engines, comprising an intermediate silencing device for connection to the exhaust manifold of an internal combustion engine, and a final silencing device series connected to the intermediate silencing device, in which the final silencing device comprises, within an envelope, a number of spaced annular members, intersected by radial partition walls, forming series of chambers of different size, which occupy the peripheral portion of the envelope and open towards the axial portion of this latter, leaving this axial portion substantially free for passage of the flow of exhaust gases, and an idle fan is provided for acting onto the passage for the exhaust gases and onto a passage for additional air, which passages join downstream the fan into an exhaust nosepiece. Some annular members are made of a catalytically active material in order to exert a purifying action on the exhaust gases.

Abstract: A silencer comprises a chamber with internal baffles mounted on a rod so that they can be manually reciprocated to scrape deposits off the chamber wall. A head at an end of the rod protruding from the chamber is screwable to a chamber end wall to hold the rod and baffles fixed during normal operation of the silencer. Loose material is expelled through a drain plug. The inlet and outlet are provided by a single through pipe which houses a tube separated into compartments by a partition. Gases enter the upstream compartment and flow through perforations in the tube and pipe into the chamber interior, then into an inverted trough through further perforations into the downstream compartment and the outlet. The chamber may be partly filled with water or a liquid cleanser, and may have cooling means.

Abstract: A rotational mechanism to be disposed midway in a fluid passage may be utilized in a silencer, rotary pump, or the like. The mechanism is essentially provided with a casing defining a spherical chamber, a pair of shafts respectively having axes passing through the center of the interior space of the casing and crossing each other in a plane substantially perpendicular to the flow direction of the fluid, and a pair of impellers having at least two flat plate vanes and at least two bent vanes alternately positioned to the flat plate vanes. The impellers are related to each other such that one flat plate vane is abutted on one bent vane of the other impeller so that every two vanes can constantly partition the spherical space to be able to diminish the noise of the flow or to transport the fluid as a rotary pump with one impeller being driven and the other impeller being idly rotated, by making isolated spaces of different volume for creating the force of pushing away the fluid.