59 results about "Surface drag" patented technology

This application describes garments (2), for example swim suits or other sports or athletic garments, in which a plurality of panels (10-22&30-44) are laminated on the outer surface of a base layer (4) of stretchable elasticated fabric to offer (in the case of a swim suit) improved performance for competitive swimmers through a reduction in surface drag, a reduction in form drag and/or improved stability in the water.

A stack of laminated transparent lenses consists of two alternating optically clear materials in intimate contact. The materials are a plastic lens and clear adhesive. The adhesive is uninterrupted. The lens and the adhesive have refraction mismatch of less than 0.2. A tab portion is part of each lens acts as an aid in peeling way the outermost lens after contamination of the lens layer during racing conditions. The lens stack can be mounted to the posts on the face shield or laminated directly to a windshield. The lens stack can be applied to an airfoil. During a race, as mud and dirt are accumulated, the top lens of the lens stack on the airfoil can quickly be removed revealing the next (clean) lens in the stack.

The invention discloses a bionics-based underwater jet surface drag reduction test device, which comprises a jet part, a power input assembly, a water distribution assembly, a moving assembly, a magnetic fluid sealing assembly and a signal processing assembly, wherein the motor of the power input assembly is connected with the input shaft of the jet part via a first coupler; the output shaft of the jet part is connected with a torque signal coupler of the signal processing assembly via a second coupler; the signal processing assembly and the jet part are arranged on the moving assembly; the water inlet pipe of the water distribution assembly is connected with a water inlet pipeline of the jet part; the water outlet pipe of the water distribution assembly is communicated with the water outlet pipeline of the jet part; and the jet part is sealed via an axial sealing assembly. The bionics-based underwater jet surface drag reduction test device has the beneficial effects that the jet surface drag reduction effect test and the non-smooth surface structure drag reduction effect test can be realized, and when the jet surface structure drag reduction effect evaluation is carried out, and a test sample can be processed into a jet hole structure with a different aperture shape, a different aperture size, a different arrangement form and a different inclination angle.

The invention discloses a design method of a blade surface drag reduction micro-texture, and belongs to the field of blade drag reduction. According to an impeller blade model, a flow field domain isestablished; numerical simulation is carried out on the flow field domain, a streamline graph of the middle section of a blade in the height direction is obtained, and accordingly a blade pressure surface, a boundary layer separation area and a suction surface backflow area serve as a micro-texture placement area; the micro-texture placement area is closely attached to a blade wing-shaped arrangement micro-texture section, and the micro-texture placement area sweeps on the surface of the blade in the height direction of the blade to form ribs or grooves; finite element simulation is conductedon the blade model with the rib or groove micro-texture to optimize the placement position and the section shape of the micro-texture, the placement position and the section shape of the micro-texturewith the best drag reduction are obtained, and accordingly the blade surface drag reduction micro-texture is constructed. The drag reduction of the optimized blade surface drag reduction micro-texture reaches 5-10%, the energy consumption is reduced, fuel resources are saved, and the design method of the drag reduction micro-texture can be applied and popularized in other fields.

The invention belongs to the drag reduction field of an aircraft body, in particular to a high-speed moving body microbubble drag reduction structure in water. The structure comprises an air pump, anair supply pipeline, an air cavity, a porous ceramic, a multifunctional sensor, an electronic pressure regulating valve, an electronic flowmeter, a control device, an aircraft body and a power unit; the whole structure is symmetrical, the power device is located at the tail of the vehicle, other devices are located in the body of the vehicle, the air pump is connected with the air cavity through the air supply pipeline, the air supply pipeline is a hose, the air supply pipeline is provided with an electronic pressure regulating valve and an electronic flowmeter, the air cavity is in close contact with the porous ceramics, and the porous ceramics has a multifunctional sensor. By means of the drag reduction method of penguin-like micro-bubble group covering the surface of the vehicle, when the acceleration is needed suddenly, the wet area changes little and the manipulation performance is very good during the voyage. The mechanism designed in this paper mainly reduces the surface drag, which is not restricted by the strict size. Moreover, the application of the surface drag reduction will not destroy the original design shape of the vehicle, and can ensure the hydrodynamic characteristics.

One kind of fluid friction force reducer is arranged between fluid to be resistance reduced and object surface. It consists of turntable, bearing, rack, movable walls and subsidiary parts. The movable walls around the turntable move with the turntable and have their parts contacting fluid moving with the fluid to reduce resistance to the fluid. Each of the movable walls consists of several layers of wall, and the wall layers can slide freely in fixed direction. Between different wall layers, lubricating fluid is filled, and the internal fluid and external fluid are maintained in balanced pressure. There may be subsidiary movable walls inside the device. The present invention may be used in different fluid resistance reducing fields.

The invention discloses a design method of a micro texture having a flat wall surface drag reduction function, and belongs to the field of surface texture design. According to the gas flow rate, an area, namely a buffer layer between a viscous bottom layer and a logarithmic law layer, where the wall shear stress is generated is determined by combining a boundary layer theory. Dimensionless treatment is performed on the size, and the thickness of the buffer layer is calculated so as to determine the height range of the micro texture. According to a Reynolds formula, the critical point of the fluid flowing from the laminar flow to the turbulent flow is calculated, and the arrangement area range of the micro texture is obtained. According to the two data, resistance reduction micro texture design is carried out, CREO software modeling is utilized, simulation is carried out through flow field simulation software FLUENT, the micro texture resistance reduction situation is analyzed, characteristic parameters of the micro texture are optimized, and the design of the flat-wall resistance reduction micro texture with the resistance reduction effect is achieved. The boundary layer theory isadopted, micro texture parameter design is conducted through layering and positioning of the turbulence area, the size design range of the drag reduction micro texture can be effectively narrowed, thesimulation amount is reduced, and the resource cost is saved.

The invention provides a measuring method of the interface sliding length of a stepped bearing. The measuring method of the interface sliding length of the stepped bearing comprises the steps of (1) setting measurement working parameters, carrying out pre-adjustment on the measurement working parameters, (2) measuring the thickness of oil film, (3) calculating the sliding speed, and (4) calculating the sliding length. The measuring method of the interface sliding length of the stepped bearing is reliable and easy to achieve, and due to the fact that a miniature sliding block bearing lubricating oil film measuring instrument is used for measuring the interface sliding length of the stepped bearing under the condition that the thickness of the lubricating oil film is of a micron/submicron level, important instructive data are provided for achievement of the purposes of reducing friction, surface resistance and power consumption, and prolonging the service life of a precise electromechanical system in the design of the precise electromechanical system.

An all-terrain sled that allows a user to easily pull cargo over any terrain. The sled includes a bottom shape that provides, with forward movement, lift over soft terrain. Cut out areas in the bottom of the all-terrain sled reduce surface drag by minimizing contact area. A leading edge of the cut out area may be disposed with an angle that can move soft surface material, such as sand, into the cut out area. A trailing edge of the cut out area may be disposed with an angle that can provide lift for the sled when moving it forward while guiding the material out to the side of the sled. The sled may include wheels on each side at one end of the sled for ease of movement over smooth terrain.

The invention brings forward a captive balloon limited wind speed static balance characteristic ground surface drag simulating test apparatus and method. A captive balloon scaled model and a dragging vehicle are comprised. Limited wind speed static balance characteristic analysis of a captive balloon is completed through a ground trailer dragging method. In the design of the test, according to the trailer performance, buoyancy, aerodynamic, gravity and other factors, a certain shrink ratio is set (the shrink ratio is not greater than 5: 1, far less than the wind tunnel test shrink ratio, closer to the real results), and the model after the scaling ensures a same shrink ratio between the outside force applied to the captive balloon and the moment of the captive balloon so as to guarantee that static balance characteristics can reflect the real captive balloon characteristics.

The invention provides a gravity circulating water tunnel for underwater complex surface anti-drag measurement. The gravity circulating water tunnel comprises a power system. The power system comprises a high water tank provided with a water outlet, used as a water source of the gravity circulating water tunnel, and outputting water from the water outlet; a liquid level measuring device used for measuring a liquid level in the high water tank in real time, and outputting a measured liquid level signal; a liquid level control system connected with the liquid level measuring device and used foradjusting the liquid level in the high water tank according to the measured liquid level signal to keep the liquid level constant; a flow rate adjusting device arranged on a water flow path behind thewater outlet of the high water tank and used for controlling a flow rate in order to make the flow rate reach a set value. The gravity circulating water tunnel can realize a variable speed in a widerange under a limited experimental space, can improve the uniformity of a flow field, can accurately control the flow rate at a centimeter level, and can be used for the accurate measurement of underwater complex surface drag.

The invention relates to an aerofoil blade of ridged surface drag reduction. The aerofoil blade of ridged surface drag reduction is used for reducing flow resistance and energy loss in operation of a pump and a draught fan, particularly, V-shaped ridged structures are arranged on the surface of the aerofoil blade, relative distance sizes among the ridged structures are set to be a, h and s, when airflow flows through a blade passage, stable secondary vortexes are formed in ridged structure gullies, and viscous resistance can be obviously reduced. According to the aerofoil blade of ridged surface drag reduction, resistance between the blade and the airflow is reduced, and the aerofoil blade of ridged surface drag reduction has the advantage of reducing the energy consumption.

A test device for a non-smooth hydrofoil surface drag reduction effect test provided by the invention comprises a driving device, a transmission unit, a test unit capable of changing hydrofoil surface test sample pieces, a water supply device, a support and a controller. The driving device is provided with a torque measurement portion, the output shaft of the torque measurement portion of the driving device is coupled with the input end of the transmission unit, and the output end of the transmission unit is fixedly connected with the test unit; the water inlet pipeline and the water outlet pipeline of the water supply device are communicated with the test cavity of the test unit; the driving device, the transmission unit and the test unit are all installed at the sliding area of the support, and the water supply are is installed at the non-sliding area of the support; the control end of the driving device is electrically connected with the control end of the controller; and the signal output end of the torque measurement portion of the driving device is electrically connected with the signal input end of the controller. The test device for the non-smooth hydrofoil surface drag reduction effect test is accurate in measurement result; and moreover, the test sample pieces are easy to change and can be supplied to the test device with no need for an extra power system, and the test device for the non-smooth hydrofoil surface drag reduction effect test is in the closed circulation mode, and reduces the cost and external disturbance.

A preparation method of a sandwich-structured intelligent hydrogel material drag reduction surface belongs to the technical field of surface drag reduction. The method comprises the following steps: preparing a required solution, making a resin template through a 3D printing technology, sequentially making three surface films, and dissolving the resin template by a tetrahydrofuran solution to realize demolding in order to complete the production of the sandwich-structured intelligent hydrogel material drag reduction surface. An ultrafine heating screen controls the temperature of temperature-sensitive hydrogel in order to change the volume of the temperature-sensitive hydrogel, so the dimension change of grooves in the drag reduction surface is realized, thereby a navigation body can adapt to the structure of a flow field structure in an all-condition state, the wall surface friction resistance is reduced, and energy is saved.

Dual loin knife blade members, in the form of a Z-blade and two styles (tabbed and non-tabbed) of J-blades, for use with knife assemblies in loin pulling machines for pork processing operations. The Z-blade knife comprises a shelf portion of extended length, formed of two separately-shaped blade portions, to maximize to the allowable customer dimensional length specification for the meat shelf being cut, while not cutting into and exposing the red meat of the pork loin eye. The J-blade, of either the tabbed or non-tabbed style, includes lower sweeping radius blade portions allowing the J-blade to lie closely adjacent and generally conform to the profile of the underlying split conveyor belt bed shape. The profiles for the present Z-blades and J-blades permit substantially increased yield in pork loin processing operations, reduced subsequent hand-trimming labor, as well as extended blade wear. A method is also disclosed for manufacturing the Z-blades and J-blades, resulting in increased wear, less surface drag on blade-related components and minimizing premature tab breakage on the tabbed-style J-blades.

An airboat that may include an engine that is mounted to the hull of the airboat at an angle, and at least one propeller mounted to the hull of the airboat at an angle. The canted engine and propeller design may facilitate a lower center of gravity, a lower average center of thrust above the waterline, air induction for reduced surface drag, the lowering of torque roll forces, less overall boat height, and fuel efficiency with a reduced level of noise.

The invention relates to the field of testing devices, and discloses a surface drag reduction simulation testing device for an underwater vehicle under the deep-sea high-pressure environment. The device comprises a high-pressure sealed cabin and a hydraulic cylinder, wherein the high-pressure sealed cabin is equipped with a sealing cover, and the sealing cover is equipped with a watertight joint;the hydraulic cylinder is fixed at one end of high-pressure sealed cabin, a piston rod of the hydraulic cylinder extends from the hydraulic cylinder into the high-pressure sealed cabin and always runsthrough the high-pressure sealed cabin in the movement process, the part, which is located in the high-pressure sealed cabin, of the piston rod is connected with a surface micro-structure underwatervehicle model and a tension sensor, one end of the tension sensor is connected with the surface micro-structure underwater vehicle model, the other end is connected with the piston rod, and a wire onthe tension sensor is connected with the watertight joint. The simulation testing device can simulate the deep-sea high-pressure environment, and solves a problem that the existing devices can only simulate ships or vehicles sailing on the water surface or in shallow water areas. The device is simple in structure, easy to operate and good in experimental effect.

An apparatus for exploring the ocean floor including a geo-magnetic sensor is disclosed. The apparatus comprises an upper frame which has an airplane shape in order to minimize surface resistance according to the resistance of ocean currents and seawater when moving inside the ocean floor and where multiple hollow holes are formed on the surface thereof; a lower frame which is coupled with the lower part of the upper frame, which includes a rectangular geo-magnetic sensor having a hollow hole inside thereof, where multiple hollow holes are formed on the surface thereof at regular intervals in order to minimize surface resistance according to the resistance of ocean currents and seawater when moving inside the ocean floor, and which is designed to facilitate submerging into the ocean floor; and a control unit which is mounted inside the upper frame in order to control the driving of the geo-magnetic sensor. The lower frame is coated with a waterproof film on the inside surface in order to prevent the geo-magnetic sensor from being in contact with seawater.

The invention provides a device and method for testing the drag reduction performance of a super-hydrophobic surface and belongs to the technical field of surface drag reduction performance testing. The problems that existing super-hydrophobic surface drag reduction performance test is low in accuracy, limited in use, high in cost, complex in test process and poor in temperature characteristic aresolved. The device of the invention comprises a water tank, a test flow channel mechanism, a frictional resistance detection mechanism and a data processing mechanism, wherein the test flow channel mechanism is formed by sequentially connecting a water tank outlet, a water pump, a throttle valve, a flow meter and a spray pipe through a water flow pipeline; the frictional resistance detection mechanism comprises an elastic unit, a lever, a hinge and a displacement sensor; and the displacement sensor is in communication connection with the data processing mechanism. The device and method are mainly used for testing the drag reduction performance of the super-hydrophobic surface.

The invention provides a preparation method for a floor cloth used by a motor-train set and belongs to the technical field of synthetic rubber. The method includes the following steps: (1) baking glue; (2) plasticating natural glue; (3) preparing material; (4) mixing the material; (5) adding a vulcanizing agent; (6) performing vulcanization. The prepared floor cloth used by motor-car groups has good elasticity, the impact force can be relieved, the surface resistance is large, the antiskid effect is good, the safety of passenger traveling can be effectively guaranteed the material has no pollution to the environment, has no halogen, the burning is low smoke and nontoxic mist, and is environmental protection, and the generated floor cloth used by motor-car groups has stable quality and highproduction efficiency.

The invention discloses a yaw angle-based groove type structure surface drag reduction effect prediction method, and belongs to the technical field of aerodynamics. According to the method, the design thought of the drag reduction effect prediction technology is determined according to the flow control mechanism of surface treatment of the groove type structure and the influence of the flow control mechanism on the time-average flow characteristic of the boundary layer. By selecting the specific structural form of the surface of the groove type structure and combining the test (or numerical value) test data of the surface of the flat plate, the function relationship between the drag reduction effect under the influence of the yaw angle and the influence factors is established. The relationship between the drag reduction effect and the CFD modeling parameter is established by using the slip speed theory. A flow field on the surface of the groove type structure on the smooth surface is simulated by means of a modeled CFD program. Compared with the prior art, the method has the advantages that the prediction efficiency of the surface drag reduction effect of the groove-shaped structure can be improved, meanwhile, the action effect under the influence of the yaw angle is accurately predicted, and the method is widely suitable for surface drag reduction design work of the groove-shaped structure of an industrial product in a complex flowing environment.