63results about How to "Suppress cavitation" patented technology

The present invention relates to a pilot type hydraulic overflow valve. Its main valve body has front end cover, in said main valve body a main valve seat, a main valve buckle, a main valve core and a main valve spring are set, and said pilot valve is formed from its valve seat, valve core and pressure-regulating spring, said pilot valve is connected with said main valve. Said invention also provides the structure of main valve and pilot valve, and provides the application range of said valve.

A power generation apparatus that suppress cavitation includes a first on/off valve provided between a steam generator and an expander in a circulating channel; a bypass channel connected between an area between the steam generator and the first on/off valve and an area between the expander and a condenser; a second on/off valve provided in the bypass channel; a third on/off valve provided between a pump and the steam generator; and a controller. When stopping the pump, the controller outputs a control signal that stops the pump, a control signal that closes the first on/off valve, a control signal that opens the second on/off valve, and a control signal that closes the third on/off valve. In the case where a predetermined condition has been met, the controller outputs a control signal that closes the second on/off valve.

The present invention is a reversible pump-turbine installation position in a vertical shaft instead of in a conventional underground powerhouse or deep concrete powerhouse. The required plant cavitation coefficient may be achieved by simply boring a vertical shaft to the required depth rather than routing the water flow to and from a deeply buried powerhouse. A pneumatically controlled pressure relief valve may be incorporated into this invention.

A vibrationproof device which is a liquid sealed vibrationproof device includes a tubular first mounting member (3) that is connected to either one of a vibration generating portion and a vibration receiving portion, a second mounting member (4) that is connected to other one, an elastic body (5) that elastically connects the first mounting member (3) and the second mounting member (4), and a partition member (8) that partitions a liquid chamber (7) of the inside of the first mounting member (3) into a main liquid chamber (7A) of an upper side having the elastic body as a portion of a wall surface and an auxiliary liquid chamber (7B) of a lower side, and a restricting passage (80) which communicates with the main liquid chamber (7A) and the auxiliary liquid chamber (7B). In addition, a first liquid (L1) is contained as a main liquid and a second liquid (L2) which is insoluble in the first liquid (L1) is contained as an added liquid in the sealed liquid (L), and the vapor pressure of the second liquid (L2) is higher than the vapor pressure of a main component of the first liquid (L1) in the same temperature and a specific gravity of the second liquid (L2) is lighter than a specific gravity of the first liquid (L1).

In a gear pump, an outer inner wall surface of a suction port which is located on a downstream side in a rotor rotation direction, that is, a first inner wall surface, is located inward of a bottom land between internal teeth of an outer rotor, and the suction port has a shallow portion extended inward from the first inner wall surface on the downstream side in the rotor rotation direction, and a deep portion that is formed so as to be continuous with the shallow portion and that is deeper than the shallow portion. Communication between an inter-tooth chamber and the suction port is cut off with the inter-tooth chamber facing only the shallow portion.

A blade for a runner of a Francis turbine having a throat diameter (Dth), the blade including: a maximum thickness of no less than 0.03 Dth and a leading edge having a maximum lean angle of no less than 45 degrees, wherein the lean angle is defined by a vertical line and the leading edge.

The invention provides a curved culvert type marine propeller, relating to marine propellers. The curved culvert type marine propeller mainly comprises a coupling component, a propeller shaft, a curved culvert, propeller blades and a tail cone, wherein the curved culvert type marine propeller is driven to rotate according to a rotation direction by a ship shaft so as to drive a ship to travel forwards. When the ship travels forwards, the cross section diameter of the front edge of the culvert is far greater than that of a throat of the culvert, resistance is generated by the front edge of the culvert, then, the hydrostatic pressure of a water absorbing area in the front edge of the culvert is increased, thus, the air bubble limit of the propeller is delayed, and the degree of cavitation is lowered, so that noise and vibration are lowered, the cavitation is lowered, and the performance of the propeller is improved; blade tips of the propeller blades of the curved culvert type marine propeller are connected together with the internal surface of the curved culvert, so that the curved culvert type marine propeller can be high in structural strength and rigidity and is suitable for being made from composite materials which are represented by carbon fiber reinforced plastics.

A method to dispose at least one air guiding tube between a penstock and a water turbine installed on a dam to form negative pressure at an outlet of the air guiding device by the water kinetic energy produced from high speed of water flow to take in external air for pressurizing, so as to produce a plurality of pressured air bubbles mixed into the water. The water with pressured air bubbles would be decompressed when flowing to an exit of the penstock and has their volumes increased, so as to enhance the water kinetic energy for driving the water turbine more efficiently; meanwhile the method can prevent from production of cavities and further avoid damages of the components of the water turbine from cavitation.

An air conditioner includes an outdoor fan and a refrigerant circuit having a compressor, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger connected to each other. An expansion valve refrigerant discharge control, in which the compressor is driven in a state where the outdoor fan is stopped and the expansion valve is open, is performed when a cooling start noise reduction condition that a state of refrigerant at inlet and outlet ports of the expansion valve is in a one-phase liquid state is satisfied when starting the cooling operation. An expansion valve normal switching control, in which an opening of the expansion valve is reduced and an operating frequency of the compressor is increased, is performed after the expansion valve refrigerant discharge control.

The invention discloses a low noise cone valve. A center hole working as an oil inlet is formed in the bottom surface of a valve body; a valve sleeve is disposed in the center hole of the valve body; the valve sleeve is in a threaded connection with the valve body; a valve core is covered with the valve sleeve and in sliding cooperation with the valve sleeve; the valve core is connected to the bottom of the center hole of the valve body; a valve sleeve oil outlet and a valve sleeve oil inlet are respectively formed in the upper and lower side surfaces of the valve sleeve; an oil outlet communicated with the valve sleeve oil outlet is formed in the side wall of the valve body on the valve sleeve oil outlet; an annular gap channel communicated with the valve sleeve oil inlet is formed in the side wall of the valve body on the valve sleeve oil inlet; a gap forming a valve sleeve front throttling port is formed between the front end of the valve sleeve and the inner wall of the gap channel; and the oil inlet in the bottom surface of the valve body is connected with the gap channel via the valve sleeve throttling port. The low noise cone valve is advantaged by simple structure, great manufacturability and simple operation; and valve noise can be reduced.

The invention discloses a sectional type oil nozzle and an optimization design method thereof. The oil nozzle comprises a needle valve, a needle valve body and a turbulent flow ring sleeve, wherein the needle valve and the needle valve body are coaxially matched, and the needle valve is located in the needle valve body; oil injection holes which are evenly distributed in the circumferential direction are formed in the needle valve body, turbulent flow concave cavities and flare openings are formed in the turbulent flow ring sleeve, and the turbulent flow concave cavities, the flare openings and the oil injection holes are coaxially distributed and are the same in number; and the turbulent flow ring sleeve is in threaded connection with the needle valve body, adjacent boundaries are consistent in shape and are in close fit, and the structure can enhance the circulation performance and the atomization performance of the oil nozzle at the same time. Based on the sectional type oil nozzle, a transparent oil nozzle internal flow and spray visualization experiment table is established; factors, levels and indexes of sectional nozzle structure design are extracted, an experiment is carried out based on orthogonal experiment design, and sensitivity analysis is carried out on data; and a BP neural network model is established and trained based on MATLAB, an optimal solution combination and a multi-index weight coefficient are solved by using the model, the correctness of results is verified through carrying out a visual experiment, and the optimization of the oil nozzle design is completed.

The invention provides a method and apparatus for suppressing hydrodynamic cavitation through the use of high frequency (>500 kHz) and high amplitude (>1 atmospheres) acoustic energy. The method includes biasing a transducer driving signal to generate an acoustic field having a positive pressure halves. The resulting acoustic field is imposed on a region where cavitation is to be preempted. A cavitation preempting acoustic field in the liquid is similar in effect as using a hyperbaric confinement for imposing hydrostatic pressure, a known method for suppressing cavitation. In this regime, suppression of cavitation will be due to imposing a dominant high amplitude, high-frequency pressure field to ensure that the gaps between the compressive pulses are shorter than 10⁻⁷ to 10⁻⁶ seconds, which is less than that typically necessary to cause cavitation.

The invention discloses a throttle valve with a built-in pressure reducing drainage device. The throttle valve is characterized in that the throttle valve comprises a left end cover, a guide sleeve, athrottle valve core, a valve body, a pressure reducing valve sleeve, a drainage device, a pressure reducing spring, a right end cover and the like; a water inlet and a water outlet are respectively arranged on the valve body and the right end cover; the guide sleeve is arranged between the throttle valve core and the valve body; the pressure reducing valve sleeve is arranged in a valve body hole;the drainage device is arranged in an inner hole of the pressure reducing valve sleeve and is capable of sliding left and right; the pressure reducing spring is arranged between the drainage deviceand the right end cover and is used for adjusting the displacement of the drainage device; two groups of kidney-shaped holes with different diameters are formed in the left side of the pressure reducing valve sleeve; steps are arranged inside the drainage device; ladders are arranged at the end part of the pressure reducing valve sleeve; and a pressure reducing valve port is formed by the steps and the ladders. According to the throttling valve, water at the outlet can be led to a throttling valve port, and the pressure at the throttling valve port is basically constant no matter how high thepressure of the water outlet is, so that the cavitation inhibition effect is basically the same under different working condition pressures, and the throttling valve is applicable to various pressureapplication occasions.

The invention discloses an impeller for restraining cavitation of the back surfaces of pump impeller blades and a design method of the impeller. The impeller is composed of an impeller front cover plate, an impeller rear cover plate and a plurality of sets of blades symmetrically arranged between the impeller front cover plate and the impeller rear cover plate. Each set of blades comprises a bladeworking face, a blade back face opposite to the blade working face, a blade water inlet edge and a blade water outlet edge, a plurality of holes are formed in the lowest pressure point area of the blade back face, and all the holes are communicated with holes formed in the impeller front cover plate or holes formed in the blade water outlet edge through the same pipeline arranged in the blades. According to the pump impeller, the pressure of the back face of the blade cannot reach the environment vaporization pressure, cavitation of the back face of the blade can be restrained, the problem that the pressure from the front face of the blade to the back face of the blade is insufficient can be solved, the pressure selectable range is enlarged, and the blade back face cavitation phenomenon is restrained.

The invention provides a forming method of tin alloy electroplating bath liquid, a preparation method of a soldering tin salient point plating and the soldering tin salient point plating. The formingmethod of the tin alloy electroplating bath liquid includes the steps that a nanomaterial is modified with a polyethylene glycol polymer; and the modified nanomaterial is added into the tin alloy electroplating bath liquid, and the tin alloy electroplating bath liquid is treated through ultrasound. According to the forming method of the tin alloy electroplating bath liquid, the preparation methodof the soldering tin salient point plating and the soldering tin salient point plating, the nano-material is surface-modified through the polymer, the modified nanoparticles are evenly dispersed in the tin alloy electroplating bath liquid, the stability of the nanomaterial in the tin alloy electroplating bath liquid is improved, the ultrasound is used for dispersion treatment, the possibility of clustering of the nanoparticles is reduced, uniform deposition during electroplating of the nanoparticles can be effectively guaranteed, the nanoparticles can be effectively embedded into lattices of the formed soldering tin salient point plating, and the effect of inhibiting forming of intermetallic compounds is achieved.

The invention provides a cavitation suppression wing section device which comprises a wing section and a sliding block. The sliding block is movably mounted in the wing section. Multiple arranged grooves are arranged on any sliding face of the sliding block and the surface, in contact with the sliding face, of the wing section. Through moving of the sliding block, the grooves on any sliding face of the sliding block at least communicate with the adjacent grooves on the surface, in contact with the sliding face, of the wing section, and the grooves are used for forming at least one pressure reduction runner in the flowing direction. An inlet and outlet communicating with the pressure reduction runners is arranged on the wing section. Through moving of the sliding block, the passage cross sections between the grooves on the sliding block and the grooves on the wing section are changed to be used for adjusting the flowing capacity of the pressure reduction runners. According to the cavitation suppression wing section device, the structure is simple and compact, the adjustable pressure reduction runners can meet the specific anti-cavitation requirements of fluid machines running underdifferent work conditions, and the device has wide development space and application prospects.

The invention discloses a centrifugal pump volute for cavitation suppression and a design method and an installation method thereof, wherein the centrifugal pump volute comprises a volute body, the volute body is provided with grooves, the grooves are annular grooves and radial grooves, and the annular grooves or the radial grooves are formed in the inner side of the volute body; and fluid is accumulated in the grooves, the pressure of the position where leakage vortexes are located is improved, a low-pressure area generated by the leakage vortexes is reduced, and cavitation is restrained on the premise that hydraulic characteristics such as lift efficiency are not reduced basically. According to the design method, the grooves are designed, and the positions, the shapes and the sizes of the grooves are determined. According to the installation method, a shell, a first side plate and a second side plate are mounted according to the design result, the manufacturing quality of the shell, the first side plate and the second side plate can be conveniently controlled, the annular grooves or the radial grooves can be conveniently formed in the second side plate, the positions and the shapes of the grooves can be conveniently controlled, and meanwhile it is ensured that the width and the depth of the grooves meet the design requirement.

A hydraulic pressure control device including a valve for generating a circulating pressure to a hydraulic power transmission chamber in which power is transmitted between an input- and output side of a hydraulic power transmission element via hydraulic oil; and a valve for generating a lock-up pressure supplied to a lock-up chamber that faces the hydraulic power transmission chamber with a lock-up piston included in a lock-up clutch interposed therebetween. The hydraulic pressure control device controls the hydraulic pressures in the hydraulic power transmission chamber and in the lock-up chamber; and the circulating pressure valve has a spool to which the circulating pressure is applied as a feedback pressure and another hydraulic pressure is applied when the lock-up clutch is engaged/disengaged, and a spring urges the spool, and sets the circulating pressure to a constant first pressure when the lock-up clutch is disengaged and to a constant second different pressure when the lock-up clutch is engaged, depending on forces to the spool by the feedback pressure and on the spring.