452results about How to "Reduce cavitation" patented technology

In the embodiments described in the specification, a rim-driven propulsion pod arrangement has a cylindrical housing with a duct providing a flow path for water and a rotor assembly supported from a central shaft and containing a rotating blade row and driven by a rim drive permanent magnet motor recessed in the housing. An array of vanes downstream from the rotating blade row is arranged to straighten the flow of water emerging from the rotating blade row. Radial bearing members on the rotor have a hardness less than that of the shaft on which the rotor is supported and relatively soft protrusions are provided in the space between the rotor and the housing to limit excursion of the rotor. A thrust bearing has wedges arranged to form a water wedge between facing surfaces of the rotor and the rotor support during rotation of the rotor.

This invention relates to a double- cycle high efficient heat pipe heat exchanging system that can control the heat exchanging quantity. There are evaporator and condenser two types of heat exchangers. The number of each type is one or several that formed by connected in parallel. This system includes: condensate supplying and distributing system; gas-liquid two phases flowing and separating system; gaseous phase transmitting and distributing system, liquid phase collecting and storing system; heat exchanging quantity controlling system. The evaporator of heat pipe, condenser, gas-liquid separator, liquid storage, solution circulating pump, liquid distributor, the connecting pipeline and related controlling parts are connected together to form the double cycles controllable heat pipe system. The solution pump, liquid distributor, evaporator and gas-liquid separator are connected together to form independent working fluid cycle, which settle the problems that working fluid carrying capacity is not enough and liquid distribution is uneven.

Apparatus for the ultrasonic treatment of tissue, including: a housing having a space therewithin and an opening adapted for placement against the tissue, the housing being adapted for introducing liquid therein such that when so placed, the space is filled with liquid; and an ultrasonic power source that introduces ultrasonic vibrations toward the damaged tissue, said vibrations having a frequency and power level sufficient to produce cavitation of the liquid at or near the surface of the tissue.

A variable marine jet propulsion system incorporates a motor, a variable-pitch propeller pump in a spherical housing, a variable housing and a variable inlet duct, and a microcontroller. The pump, the nozzle and the inlet are controlled by the microcontroller, which is programmed to control the pump as a continuously variable power transmission for maintaining efficient motor operation, the nozzle for maintaining efficient pump operation, and the inlet for maintaining efficient recovery of the total dynamic head of the incoming water. The spherical pump housing maintains close fits to the propeller vane tips for more efficient operation at all pitches, including zero and reverse pitches. Zero pitch results in no effective pumping action, effectively a true neutral in fluid power transmission. Reverse pitch in combination with the large variable nozzle provides reverse flow and consequently reverse thrust, which eliminates the need for the “backing bucket”.

A variable displacement vane-type fluid pump is provided which permits improved regulation of the pump discharge such that the pump can meet the various requirements of lubrication for internal combustion engines at all speeds with minimized use of power. Of course, the vane pump may also be utilized in a wide range of power transmission and other fluid distribution applications. The variable displacement vane pump of the invention may utilize both hydrostatic and mechanical assistance in radially positioning its vanes to ensure efficient and quiet operation of the pump and to facilitate priming of the pump. The vane pump of the invention may also use both hydrostatic and mechanical actuators to control the position of its containment ring or eccentric ring and hence, regulate the output of the pump. According to yet another aspect of the present invention, to prevent inlet flow restriction or cavitation, a valve may be provided to permit some of the pump outlet or discharge flow to bleed into the pump inlet to provide needed velocity and energy to the fluid flow into the pump inlet.

Disclosed is a liquid-sealed vibration isolator (10) provided with a main liquid chamber (42), a portion of the chamber wall of which is formed from a vibration isolating base (16), a subsidiary liquid chamber (44), a portion of the chamber wall of which is formed from a first diaphragm (38), and a first orifice flow path (50) which connects both liquid chambers, wherein a high-frequency second orifice flow path (54) which connects the main liquid chamber (42) and the subsidiary liquid chamber (44) is formed on a partitioning body (40), and a second diaphragm (60) is provided on the opening (59A) of the second orifice flow path (54) on the side of the main liquid chamber. The outer peripheral portion (60A) of the second diaphragm is held by the partitioning body (40) in a liquid-tight manner, and the second diaphragm (60) abuts the peripheral edge portion of the opening (54A) so as to block said opening with a flexible membrane section (60B) which is provided on the inside of the second diaphragm (60). Moreover, a through hole (74) is disposed on the flexible membrane section (60B) at a position which does not overlap the opening (54A).

A Francis turbine with an improved shape of blades, which can reduce cavitations generated on the surface of the blades or reduce the secondary flow around the blades, is provided. A Francis turbine comprises a rotating shaft, a crown, a plurality of blades, and a band. The crown can rotate with the rotating shaft. The blades are circumferentially arranged on the crown, each of which including an inner end as a trailing edge. The band is coaxially coupled with the crown by the blades. The rotating shaft, the crown, the blades, and the band as a whole rotate toward a turbine direction during a turbine operation. A projected profile of the trailing edge on a perpendicular plane, which is perpendicular to a center axis of the rotating shaft, is curved toward a direction opposite to the turbine direction at least in the crown side.

A control valve that reduces noise and controls flow includes a slotted cylindrical skirt and / or a tapered metal ring. The metal ring has a tapered external surface for engaging a matching tapered bore within a valve housing. One embodiment is directed to a control valve including a housing defining a central orifice in fluid in communication with an inlet port and an outlet port, and a movable valve plug assembly having a skirt portion slidably engaged within the central orifice to control fluid flowing through the housing. The skirt portion defines a plurality of openings, which can be slots, to gradually control the flow of fluid through the housing while reducing cavitation. A method of controlling fluid flow in a process includes receiving fluids via an inlet port of a control valve, and controlling the flow of the fluid via a movable skirted valve plug with a plurality of tapered slots.

The invention discloses a kind of pure water off-loading overflow valve consisting of a king pressure control valve and pure water electromagnet switching ball valve. The king pressure control valve consists of a king valve and a guide valve. The king valve plug having a secondary throttling cone valve structure with high pressure conduction is effective to restrain air muddy. The guide valve having cone valve structure with damping piston can increase motion damp and advance working stability of the overflow valve; constant pressure precision of the overflow valve is increased, if set constant liquid damp at the entrance of the guide valve. The electromagnet switching ball valve is generated by dry-type DC electromagnet, and is switched fast by mechanism of force amplification. The invention achieves zero leakage by sealing directly valve plug and valve cover, valve cover and valve body, improve static performance of the overflow valve by add valve port damper and achieve fast over-loading by electromagnets with larger thrust. The invention has characters of good versatility, integrated multifunction and being easy to standardize so as to fit to work under conditions of middle and high pressure water medium.

A boat stabilizer that is attachable to the anti-cavitation plate or other structure of the lower drive unit of a boat motor without permanently modifying the structure of the anti-cavitation plate or other structure is provided. The shape and size of the boat stabilizer causes the stabilizer to effectively harness and control the thrust energy generated by the propeller resulting in improved thrust and fuel efficiency. Due to various features, the drag associated with the boat stabilizer is kept to a minimum. Finally, decals and other decorative elements are integrally embedded into the top surface of the inventive boat stabilizer using in-mold decoration (“IMD”) technology which makes the elements resistant to ultra-violet light, virtually indestructible and highly appealing. A boat motor, a method of attaching a boat stabilizer to a boat motor and a method of molding a boat stabilizer having at least one decorative element integrally embedded in the top surface thereof are also provided.

A sacrificial body mitigates cavitation damage to components within a pump. The sacrificial body is mounted in the pump so that flowing fluid passes over the sacrificial body, which causes the sacrificial body to shed electrons into the flowing fluid in the vicinity of the cavitation. The excess electrons tend to suppress hydrogen ions from releasing, which can mitigate cavitation. The sacrificial body is formed of a material having less resistance to corrosion due to the flowing fluid than the components of the pump. Needles are attached to the sacrificial body for immersion in the flowing fluid to facilitate the release of the electrons for the sacrificial body.

The invention belongs to the field of circulating cooling water conveying systems and particularly relates to a method for optimizing a circulating cooling water convey system. The method comprises acquisition of date in all procedures of the circulating cooling water system, date analysis, and system optimization. The model number of a water pump actually needed in the system is determined through data acquisition and analysis, and valve loss, local circumfluence, high-low pressure blending, pipeline blockage and unnecessary loss in the system are correspondingly eliminated. By adopting the method, unfavorable working conditions caused by overlarge resistance of the circulating cooling water system, such as overlarge electric motor power, over temperature, cavitation erosion on a water pump, low operation efficiency and the like are improved, and most importantly, the pipeline characteristic matching problem in the circulating cooling water system is solved. By adopting the tailor-made water pump to meet actual needs, the efficiency of the machine set is more than 15% higher than that of the original pump, the cavitation erosion phenomenon is remarkably relieved, the electric motor is protected, the service life is longer, the energy saving effect is greatly improved to reach above 25%, and the actual operation efficiency of the system is greatly improved.

A system having reduced gas interference that includes a fluid chamber and a resonant sensor device in fluid communication with a fluid in the fluid chamber. The system includes a fluid control device adapted to change at least one of the fluid flow or pressure within the fluid chamber to achieve substantial wetting of surfaces in proximity to the resonant sensor device. Fluid surfaces of the system can include a material to increase the wettability (e.g., hydrophilicity) of the fluid surfaces.

The invention relates to a multi-cavity baffle type electrolytic milling and grinding complicated machining tool cathode and a method and belongs to the field of electrolytic milling and grinding complicated machining. According to the multi-cavity baffle type electrolytic milling and grinding complicated machining tool cathode and the method, by arranging a plurality of sector-shaped blind hole cavities in the tool cathode, and arranging an annular baffle above a cathode diamond abrasive particle layer, the defect that supplied liquid in a machining gap is not sufficient is overcome, the flow field uniformity is improved, and the stability and the machining precision of electrolytic milling and grinding complicated machining are effectively improved.

A fluid end assembly includes a fluid end and a plurality of valve assemblies each located within a cavity that has curved internal profiles. The curved internal profiles of the cavities are concaved outward. A plunger is included to provide variations in pressure within the fluid end so as to facilitate movement of the working fluid. A discharge plug is included in communication with the fluid end. The discharge plug may include a curved profile along an inner surface that corresponds with one of the cavities therein. A suction plug is releasably coupled to the fluid end and includes a curved profile along an inner surface. The suction plug also includes a recess for acceptance of a spring retainer. The spring retainer is included to support a suction valve assembly.

A method for controlling a histotripsy using a confocal fundamental and harmonic superposition combined with hundred-microsecond ultrasound pulses, including: 1) positioning a target tissue by a monitoring and guiding system and adjusting a position of the target tissue to a focal point of a transducer; 2) first stage: controlling the confocal fundamental and harmonic superposition combined with hundred-microsecond ultrasound pulses to form a shock wave in a focal zone; wherein a negative acoustic pressure exceeds a cavitation threshold; an inertial cavitation occurs to generate boiling bubbles; the boiling bubbles collapse and achieve partial homogenization of the target tissue; 3) second stage: controlling the confocal fundamental and harmonic superposition combined with hundred-microsecond pulsed-ultrasound sequences to simultaneously irradiate a target zone and further mechanically disintegrate and homogenize the target tissue.

A system and method for reducing or eliminating pump cavitation in a closed system having at least one or a plurality of fluid phase changes. The system comprises a venturi having a throat which is coupled to a reservoir tank.

A country comprehensive sewage treatment system and country comprehensive sewage treatment method belongs to the technical field of water treatment. The system includes, in a successively connected manner, a pre-treatment system for filtering suspended solids in water, a container-type integrated water treatment system, a soil infiltration system, a solar energy power supply system for supplying power to the container-type integrated water treatment system, and a process management system. The system and the method achieve dispersion and separation and integrated treatment of country comprehensive sewage, is convenient to operate and manage, is suitable for distribution characteristics of water quality and water amount of country household sewage and cultivation sewage, and overcome defects in country comprehensive sewage mixed treatment and household dispersed treatment in the prior art.

A high pressure common rail fuel system is provided including a fuel supply, a high pressure pump assembly fluidly connected to receive fuel from the fuel supply, and a gas supply system fluidly connected to provide gas to the high pressure pump assembly to create a high pressure gas fuel mixture. A common rail fuel system is fluidly connected to the high pressure pump assembly to receive the high pressure gas fuel mixture.

The invention relates to a method reducing cavitation on the surface of a half-balanced suspension rudder leaf at the tail of the ship. The method adopts the measures in the area of the half-balanced suspension rudder leaf which is easy to be cavitated: (1) the right angle at the riverside position at the lower edge of the rudder leaf is changed into fillet; (2) a guide fin is additionally added at the vertical rudder from the lower edge of the rudder leaf to the midpoint of the central line of the oar shaft; (3) a guide bar is additionally added nearby the frontage of the connection between the rubber supporting and the rudder leaf. After adopting the method of the invention, the change of the linetype of the tangential plane of the rear rudder is flat, and the vortex cavitation of a prop can still keep vortex cavitation when floats to the lower edge of the rudder leaf and does not cavitate the rudder leaf at the position; when the rudder angle turns to a certain angle, the prop vortex cavitation floated to the position does not change the performance owning to the demulcent change of pressure field; meanwhile, with the wake flow continuing to drift to the rear of the ship, the added guide bar can reduce the water flux flowing to the clearance and leads the water flow to stably slide by; meanwhile, the unavoidable cavitation is guided out of the surface of the rudder surface, thus relieving the cavitation phenomenon at the position.

The present invention discloses waterproof and oil-proof agent for papermaking industry. Acrylate monomer, cation monomer and fluroric monomer as well as dispersing emulsifier, initiator and stabilizer are emulsion polymerized under the synergistic action of ultrasonic wave irradiation and microwave irradiation to prepare the emulsified waterproof and oil-proof agent. The waterproof and oil-proof agent is added into the paper pulp or painted to the surface of paper, and can raise the water preventing and oil preventing function obviously.

A method of reducing underwater hydrofoil cavitation is described; hydrofoil steering vanes trade a small degree of efficiency for significant cavitation reduction, through perforations in the hydrofoil. Some pattern examples are discussed. A method of further cavitation reduction through surface texture variation also reduces underwater hydrofoil drag; some patterns are discussed. Combining the methods provides maximum cavitation reduction.

The invention discloses a gas-liquid dispersing and stirring device and belongs to the technical field of fluid mixing. Every blade of the gas-liquid dispersing and stirring device consists of a radially extending and highly shrinking concave, the vertex of the concave is positioned at the intersection position of the concave and a disk plane and extends perpendicularly along the tangential direction. The upper half and the lower half of an inner margin curve of every concave are asymmetric, the upper half extension length is greater than the lower half extension length, but the upper half and the lower half of an outer margin curve of the concave are symmetric; the vertical height of the inner margin of the concave is greater than that of the outer margin thereof, but the tangential extension length of the outer margin of the concave is greater than that of the inner margin thereof. The inner sides of the blades are beneficial to catching ascending bubbles and making the same disperse into a liquid phase, and in an outward extension process of the blades, the vertical height of every blade decreases gradually. The gas-liquid dispersing and stirring device has the advantages of low power consumption, high gas-liquid dispersion efficiency and mixing performance and capability of dispersing gas into a liquid phase system or liquid-solid system in an efficient energy-saving way.

Disclosed is a liquid-sealed vibration isolator (10) provided with a main liquid chamber (42), a portion of the chamber wall of which is formed from a vibration isolating base (16), a subsidiary liquid chamber (44), a portion of the chamber wall of which is formed from a first diaphragm (38), and a first orifice flow path (50) which connects both liquid chambers, wherein a high-frequency second orifice flow path (54) which connects the main liquid chamber (42) and the subsidiary liquid chamber (44) is formed on a partitioning body (40), and a second diaphragm (60) is provided on the opening (59A) of the second orifice flow path (54) on the side of the main liquid chamber. The outer peripheral portion (60A) of the second diaphragm is held by the partitioning body (40) in a liquid-tight manner, and the second diaphragm (60) abuts the peripheral edge portion of the opening (54A) so as to block said opening with a flexible membrane section (60B) which is provided on the inside of the second diaphragm (60). Moreover, a through hole (74) is disposed on the flexible membrane section (60B) at a position which does not overlap the opening (54A).

The invention discloses an orifice-plate type adjustable throttle valve and a manufacturing method of the orifice-plate type adjustable throttle valve. The orifice-plate type adjustable throttle valve comprises a valve body, a valve cover, a valve rod and valve plates, wherein at least one through hole 26 is axially arranged on each of two disk type valve plates 4, so that under the situation of same flow, not only the escaping volume of gas phase components in a pipeline is increased, but also dead area accumulation of dinas at the entrance of the orifice plate of the throttle valve and occurrence of cavitation erosion of the gas are reduced; most importantly, the exit of the orifice plate with a plurality of orifices is positioned at an intersectional zone of high-pressure jet, multiphase fluid forms a hedging energy consumption depressurizing area, so as to reduce internal kinetic energy of high-speed fluid and scour to the wall of the pipe, so that the service life of the throttle valve is greatly improved; for an equally grading throttling depressurizing pipeline, the orifice-plate type adjustable throttle valve can reduce throttling grade number of the pipeline to reduce the operating cost of a company. The orifice-plate type adjustable throttle valve can be widely applied in fields such as metallurgy, mine, infrastructure, wastewater treatment, and port shipping, as well as in pipelines for conveying multiphase mixed fluid in industries.

The invention provides a novel efficient hydrofoil. The novel efficient hydrofoil comprises hydrofins and a hydrofoil strut. The hydrofins are fixedly mounted below a naval ship through the hydrofoil strut, and the outer surfaces of the hydrofins are provided with antidrag structures composed of rough belts, grooves, pits or texture structures. The hydrofins with the antidrag structures have high lift-drag ratio when moving in the water, frictional drag and viscous drag of the hydrofoil to the water can be reduced, energy efficiency of driving delivery tools such as foilcrafts can be improved, and the novel efficient hydrofoil has the advantages that ship navigation speed is improved and energy conservation and emission reduction are realized.

A marine propulsion device such as an outboard motor includes a submersible electric motor having a propeller connected directly with the drive shaft of the motor. The motor is an efficient brushless motor having symmetrical elliptical coils connected with a stator which generate magnetic flux when current is passed through the coils to rotate a rotor for driving the drive shaft. The motor is arranged in a housing having a nozzle connected with a rear portion thereof which surrounds the propeller to reduce cavitation. Cooling fins are provided on the outer surface of the housing to assist with cooling the motor and a motor controller arranged in the housing.