157results about How to "Small drag coefficient" patented technology

An ultra-large truss type floating marine platform is composed of floating drums dispersed on water surface, a working platform above water surface, and connecting rods. Its advantage is high stability.

The invention relates to a preparation method of a polymer weak gel deep profile control agent. The preparation method comprises the following steps of preparing sodium carboxymethyl cellulose and distilled water into sodium carboxymethyl cellulose water solution of which the mass percentage is 1%-2%; adding acrylamide of which the mass is 2-8 times as great as that of the sodium carboxymethyl cellulose into the sodium carboxymethyl cellulose water solution, and then adding a cross-linking agent which accounts for 0.01%-2% of the total weight of the sodium carboxymethyl cellulose and the acrylamide; enabling nitrogen to enter into a closed system and isolating the air, and adding an initiating agent which accounts for 1%-2% of the total mass of the sodium carboxymethyl cellulose and the acrylamide; and discharging after carrying out constant-temperature reaction for 4-12 hours under the temperature of 30-60 DEG C. According to the preparation method disclosed by the invention, the acrylamide is grafted to the sodium carboxymethyl cellulose, polymer weal gel with a mesh structure is formed under the action of the initiating agent and the cross-linking agent, and a polymer weak gel system integrates the advantages of the sodium carboxymethyl cellulose and the acrylamide.

The invention discloses a dynamic base station for AUV recovery, belongs to the technical field of underwater robot recovery, and aims to solve the problems of instability in docking recovery, difficulty in operation, large drag resistance and certain potential safety hazards existing in the prior art. The dynamic base station comprises a recovery base station body, two attitude regulators symmetrically arranged on the recovery base station body, a connecting ring fixed on the recovery base station body, a guide cover, a locking device, a position detector, and a main controller, wherein one end of the guide cover is coaxially and fixedly connected with one end of the connecting ring, and the other end of the guide cover is a free end with opening adjustable; one end of the locking deviceis fixedly connected with the other end of the connecting ring, and an underwater robot which enters the dynamic base station is clamped or loosened through the locking device; the position detector is fixedly connected with the other end of the locking device; and the main controller is arranged in the recovery base station body, the rotating speed of the two attitude regulators is controlled through the main controller, and the main controller receives the detection signals of the position detector to control the locking device to clamp or release the underwater robot.

The invention discloses a method for carrying out streamline-form thickening on airfoil shape tailing edge, which is mainly applied to the improvement field of wind machine blades; the reformed airfoil shape designed by the method has better pneumatic performance than the original airfoil shape; in the proper functioning angle of attack range, not only the lift coefficient of the improved the airfoil shape is increased, but also the control method provided by the invention guarantees the streamline-form characteristics of the airfoil shape pressuring surface, thereby the resistance coefficient of the airfoil shape is very small, the airfoil shape has higher lift drag ratio, simultaneously, is later in stall, and has good social and economic values.

The invention belongs to the technical field of heat exchangers, which relates to an enhanced heat transfer fin and a production process thereof. The enhanced heat transfer fin comprises a flat and straight substrate, wherein waveform fins which are raised on the flat and straight substrate and form certain angle with the flat and straight substrate are formed on the flat and straight substrate, reversing areas are arranged between a plurality of the waveform fins and divide the waveform fins into a plurality of groups waveform fin areas with different numbers of ripples, the wavelength and the wave amplitude of each waveform fin in each group are equal to each other, the number and the wavelength of the waveform fins of different groups are no equal to each other, and the number of the waveform fins in each group of the waveform fin area decreases in turn in the whole fin length while the wavelength increases in turn. The production process of the enhanced heat transfer fin is to put an aluminum strip on a roll forming machine to form the enhanced heat transfer fin provided with the waveform fins and the flat and straight substrate through one-step rolling. The enhanced heat transfer fin has good heat transfer property and small resistance, and is suitable to serve as a heat transfer fin of an automotive heat exchanger, a water tank radiator, a pressurizing intercooler and a wind cooling type hydraulic oil cooler.

The invention provides closed loop control of aircraft control surfaces. Closed loop control method for control surfaces includes measuring a flight metric of an aircraft during flight and calculating, using a processor, a deflection of a control surface of the aircraft based on the flight metric. The disclosed method also includes adjusting the deflection to an effective deflection level based on the calculated deflection to reduce a drag coefficient of the aircraft.

A grid fin of a supersonic velocity guided missile comprises spanwise clapboards and chordwise clapboards. An upper supper surface and a lower surface of two sides, in the length direction, of each spanwise clapboard are symmetrical wedge surfaces. A surface, located at a long edge of the front edge of the grid fin, of a fifth clapboard and an eighth clapboard is processed into a wedge surface, and the wedge surface is located on an outer surface of the grid fin. Two surfaces, located at the front edge of the grid fin, of long edges of a sixth clapboard and a seventh clapboard are both processed into wedge surfaces. Wedge surfaces of all the spanwise clapboards and the chordwise clapboards can effectively reduce interference effect from shock waves produced by the chordwise clapboards to reducing shock waves of the spanwise clapboards.

The invention discloses a wing structure. The wing structure consists of continuous wing profiles, wherein the spans of the wing profiles away from the root of a wing are 0 percent, 20 percent, 40 percent, 60 percent, 80 percent and 100 percent respectively; the ratio of wingspan to chord length is 5.50-7.24; the leading edge of the wing is a high-order curved line of an approximately parabolic shape; the maximum relative curvature of each wing profile is 7.5 percent and is positioned at a position at 17-33 percent of the chord length; the maximum relative thickness of each wing profile is 13.1 percent and is positioned at a position at 11-24 percent of the chord length; the curvature and the thickness of each wing profile tend to be increased and then decreased along the corresponding span. Compared with a parametrically-similar NACA (national advisory committee for aeronautics) 4-digit wing profile, the wing structure has the advantages that a low-speed lift coefficient is large, a resistance coefficient is small, and a large angle of stall is formed; under the condition of same flight parameters, according to the wing structure, the flight noise is low, and the lift coefficient is relatively large when an angle of attack is 25 degrees, and slowly declines when the angle of attack is greater than 25 degrees.

The invention provides a pneumatic structure for inhibiting the vortex-induced resonance of a bridge cylindrical suspender. The pneumatic structure is realized by additionally arranging a spoiler on the cylindrical suspender. The wind resistance of the suspender is obviously improved, the vortex-induced force of the suspender is reduced, the design is convenient, the construction is simple, the effect is obvious and good inhibiting effect on the vortex-induced resonance of the suspender is realized.

The invention relates to a kind of wing section used rof the ocean current electricity-generating water turbine. According to the fairly wide range of working condition of the ocean current electricity-generating water turbine, select the fairly small curvature and the fairly small greatest thickness. The ratio of the greatest thickness and length of chord is d/c=0.1570, the ratio of the greatest curvature and the length of chord is f/c=0.0229. The wing section has sacrificed part of functions under the routine angle, but meanwhile, it obtains the superior function of condition changing. Moving the position of the greatest thickness backward, can improve the reserve working capacity and also improve the left coefficient of wing section. At the point X r/c=0.95 of back edge, the wing section takes are as transition. The ratio of arc radius and chord length of wing section is R/c=0.0208. Enlarging the radius of back edge 1f wing section can weaken the influence when the slight wing stalls under a big angle, and reduce the damages objects uotside have done with the wing section.

The embodiment of the invention discloses a centrifugal fan impeller, comprising an upper blade disc, a lower blade disc and a plurality of blades connected between the upper blade disc and the lower blade disc, wherein the blades comprise a plurality of long blades and a plurality of short blades; the long blades and the short blades are alternatively distributed in the circumferential direction surrounding the impeller; the short blades are arranged at the positions of a flow channel close to outlets of the adjacent long blades; and the blade profile of each long blade adopts a line-arc-line form, and comprises an outlet-end line part, an inlet-end line part and an arc part connected between the outlet-end line part and the inlet-end line part. The embodiment of the invention has the advantages that due to the design that the line-arc-line blade profiles of the long blades are matched with the flow-distributing short blades, the resistance coefficient in the impeller is reduced, meanwhile the pressure of negative pressure areas of the long blades is increased, the vortex formed by the airflow is restrained, and the total efficiency of a fan is improved, so that the flow and the total pressure increase of the fan meet the requirements for high pressure and large flow needed by a snow blowing vehicle.

Disclosed are supersonic missile anti-drag wings. Two sets of missile wings are distributed on two sides of a missile body symmetrically. Each missile wing comprises an upper wing piece and a lower wing piece. Root chord lengths of the upper wing pieces and the lower wing pieces are both 0.52m, and stretching lengths of the upper wing pieces and the lower wing pieces are both 0.52m. The upper reflex angle of each upper wing piece is -9 degrees, and the upper reflex angle of each lower wing piece is 9 degrees. The leading edge backward sweep angles of the upper wing pieces and the lower wing pieces are both 63.6 degrees. Each upper wing piece and each lower wing piece are respectively connected with a driving mechanism. When a Mach number of a supersonic cruise missile is lower than a design point, the upper wing pieces on the two sides of the missile body deflect downwards, the lower wing pieces deflect upwards so that the area ratio of the maximum thickness portion of the wings and the leading edge inlet is 1. Upper stream passes between the wings so that occurrence of jamming is avoided. When the Mach number continues to increase and reaches the designed Mach number, the upper wing pieces on the two sides of the missile body deflect upwards, the lower wing pieces deflect downwards, and the Busemann double-wing outward position is realized. Shock wave resistance can be reduced by utilizing wave interference effect of shock wave weakening and shock wave expanding.

The invention provides a squirrel-cage type two-stage cyclone solid-liquid separation device for efficient solid-liquid separation of produced liquid from an oil-gas well. By virtue of squirrel-cage type cyclone pipes and a two-stage cyclone technology, the squirrel-cage type two-stage cyclone solid-liquid separation device is compact in structure and economic in construction cost; the squirrel-cage type cyclone pipes and a two-stage cyclone cylinder assembly sequentially complete first-stage solid-liquid separation and second-stage solid-liquid separation, so that the produced liquid can be efficiently and thoroughly separated. The device is high in adaptability, most of treatment operations are completed by the first-stage solid-liquid separation, and the second-stage solid-liquid separation is used for treating a small amount of remaining liquid under the condition of large liquid quantity and high viscosity; by virtue of the optimized design of all taper sections of the cyclone pipes and two-stage cyclone cylinders, the produced liquid is small in resistance coefficient and is kept in a high-speed rotation state; all the cyclone pipes have the same structure and the same size, so that the standardized and blocked design is realized; separated liquid is collected by a liquid collecting pipe assembly and is discharged from a liquid discharging assembly; sand grains are collected by a sand collecting pipe assembly and a sealing body and then are discharged from a sand discharging pipe; the device is high in degree of automation and easy to install, operate and maintain.

A flight automobile relates to a vehicle. The flight automobile comprises an automobile body and a lift-off device and can be vertically lifted, can suspend at ant height and can conduct super low altitude flight at a low speed or at a high speed. The automobile body comprises four basic parts of an ordinary motor vehicle as an engine, a chassis, a vehicle body and an electrical device, and the automobile body further comprises a lift-off device storage chest, a propeller, an air pump and a main shaft; and the lift-off device is made up of two layers of material having the characteristics of low density, softness, toughness and air tight property. The flight height of the automobile is controlled through controlling the air density inside the macro-cavity of the lift-off device; the flight speed and direction are controlled through controlling the propeller; and the size of the lift-off device is reduced through discharging the air inside the small cavity in the interlayer of the lift-off device, so that the lift-off device can be placed in the chest of the automobile body and the flight automobile can be restored to the size of an ordinary vehicle.

The invention discloses a wing framework of an imitation pterosaur flapping-wing aircraft. The wing framework comprises four movable arms, namely a main movable arm, a second movable arm, a third movable arm and a fourth movable arm, wherein the end part of the main movable arm is connected with a main steering engine which controls the main movable arm to swing, the main movable arm and the second movable arm are connected with each other through a secondary steering engine, the second movable arm and the third movable arm are connected with each other through a tertiary steering engine, the third movable arm and the fourth movable arm are connected with each other through a quaternary steering engine, and the main steering engine, the secondary steering engine, the tertiary steering engine and the quaternary steering engine are respectively and internally provided with a driving motor. The wing framework is covered with a thin film wing and can be used as a wing of the flapping-wing aircraft. The framework is designed by imitating a bone structure of a pterosaur; and compared with the wing framework of an imitation bird flapping-wing aircraft, the wing framework is simple in mechanical structure and relatively low in cost, and can increase the lift coefficient and reduce the resistance coefficient.

The invention discloses an intelligent integrated pump station. A control cabinet is internally provided with a controller and an alarming wireless transmitting module, wherein the controller is connected with the alarming wireless transmitting module; a top cover is arranged at the top of a barrel body; a ventilation pipeline is arranged on the top cover; an exhaust fan is arranged in the ventilation pipeline; a gas sensor is connected with the controller in the control cabinet; the controller is connected with the exhaust fan; an overhauling platform is fixed in the barrel body; a barrel wall of the barrel body is fixedly connected with the edge of a concave deposition-prevention barrel bottom; a plurality of groups of water pump fixing bases are fixed on the concave deposition-prevention barrel bottom; each group of water pump is suspended above the concave deposition-prevention barrel bottom through the corresponding water pump fixing base. By adopting the intelligent integrated pump station disclosed by the invention, the water pumps are prevented from being blocked by sludge and impurity deposition on the barrel bottom of the pump station, and cleaning and maintenance are reduced or are not needed; the intelligent integrated pump station is simple in structure and energy consumption is reduced.

The invention discloses a spraying system for a waste gas purifying tower. The spraying system comprises a spraying main pipe (1) and is characterized in that spraying branch pipes (2) are evenly built on the spraying main pipe (1), spiral sprayers (3) are evenly arranged at the bottom of the spraying branch pipes (2), and water flow entering the spiral sprayers (3) from the spraying branch pipes (2) produces layered spraying by hitting a spiral layering interface. Due to the arrangement of the spiral sprayers, the water flow entering the spiral sprayers from the spraying branch pipes produces layered spraying through hitting the spiral layering interface, the streamlined design from an inlet to an outlet in a cavity of the spiral sprayer leads to the minimum resistance coefficient, so that liquid blockage is reduced to the greatest extent, the liquid reaches the maximum flow on a pipeline with specified size, in addition, the wear resistance, the corrosion resistance, the fogging property, and the anti-blocking property of the spiral sprayer are better than those of a tobacco pipe sprayer, the cost is low, the mass production can be carried out easily, and the spraying system is suitable for popularization and application.

The invention discloses a drag reduction device for vans. The device comprises a closed bionic flow guide cover arranged between the cab of the van and the cargo compartment, a drag reduction device arranged at the rear of the van, and a bionic non-smooth surface structure arranged on the two side surfaces of the van body. By the method, the wind resistance of the van can be reduced, the vehicle speed can be increased, the vehicle stability can be increased, and the fuel consumption can be reduced during the running of the van.

The invention provides a double-wall spiral hush pipe and relates to a plastic drain pipe, and particularly relates to a drain pipe capable of sound muffling. The double-wall spiral sound muffling pipe aims to overcome the defect that an existing drain pipe is loud in noise and provide a drain pipeline simple in structure and capable of sound muffling and sound insulating. The double-wall spiral hush pipe comprises a pipe body and is characterized in that the pipeline wall is in a connection and double-layer structure, gapped through holes are evenly formed between the inner wall and the outer wall at intervals, protruding river diversion ribs are evenly arranged along the inner pipeline wall. The double-wall spiral hush pipe mainly applies to a modern construction drainage system.

The invention belongs to the field of fluid excitation devices and discloses a bidirectional active-control downstream fluid excitation device. The fluid excitation device comprises a wing, as well as one or more air inlet holes, one or more air outlet holes, sealed air chambers, and an air delivery driving device which are arranged on the wing, wherein the air inlet holes are formed in the leading edge area of the upper surface of the wing; the air outlet holes are formed in the trailing edge area of the upper surface or/and the lower surface of the wing; the sealed air chambers and the air delivery driving device are arranged in the wing and are connected with each other to form an air passage; and an air stream is sucked in from a downstream ends of the air inlet holes by the air delivery driving device, passes through the air passage and blows out from the air outlet holes. The fluid excitation device is practically applied to a wing profile of an independent entity; besides, the combination of slot suction with closed-loop control is used to provide lift force and reduce resistance; the fluid excitation device is simple in structure; and industrialized production of the fluid excitation device can be realized.

The invention relates to a drone comprising: two contra-rotating annular propellers (2, 4) defining a plane therebetween which is referred to as an equatorial plane and is assumed to be horizontal, means for driving the propellers, a load arranged below the equatorial plane, and means (20) for moving the load relative to the equatorial plane, an enclosure referred to as an upper enclosure (6) filled with a gas or a gaseous mixture having a density of less than 1 and arranged essentially above the equatorial plane, and an enclosure referred to as a lower enclosure (8) filled with a gas or a gaseous mixture having a density of less than 1 and arranged essentially below the equatorial plane, the load being placed inside the lower enclosure (8).