86 results about "Concentric cylinder" patented technology

The present invention relates to the technical field of coastal engineering, and disclosed is a method for evaluating a radiation hydrodynamic force for a concentric cylindrical structure, comprising the following steps: S1, coordinate system establishment: establishing a cylindrical coordinate system orθz and a Cartesian coordinate system oxyz by taking the intersection of the center of a concentric cylindrical structure and a still water surface as the origin, where the z-axis is vertically upward; S2, flow field division: dividing the entire flow field into an outer domain and an inner domain; S3, perforated boundary condition assumption; S4, determining radiation velocity potentials of the inner domain and the outer domain by means of governing equations and boundary conditions; and S5, by means of the expressions of velocity potential functions of the inner and outer domains, determining first-order radiation forces, added masses and damping coefficients generated by the vibration of an inner cylinder and an outer cylinder. The method takes into account both the effects of seismic and radiation hydrodynamic forces, provides accurate structural response prediction, fills the technological gap in the field of seismic analysis of concentric cylindrical structures as breakwater units, and provides a reliable basis for engineering design.

The invention belongs to the field of wireless communication, and particularly relates to a low-loss leaky coaxial cable and a manufacturing method thereof. The leaky coaxial cable comprises an inner conductor, a composite insulating layer, an outer conductor and a sheath layer which are coaxially arranged in sequence, and each layer forms a concentric cylindrical structure by taking an axis as a center. The outer surface of the inner conductor and the outer surface of the outer conductor of the leaky coaxial cable are respectively roughened, so that the contact between the inner conductor and the insulating layer and the contact between the outer conductor and the sheath layer are improved, meanwhile, a solid inner skin layer originally used for bonding the inner conductor and the insulating layer is omitted, the signal transmission performance is improved, and the service life of the leaky coaxial cable is prolonged. And the transmission loss is reduced. Compared with an existing product, the leaky coaxial cable with the surfaces of the inner conductor and the outer conductor, provided by the invention, has the advantages that the attenuation index is integrally optimized by 2.6%-5.8% under multiple frequency bands of 900 MHz to 2700 MHz on the premise of meeting the test requirements of adhesive force, standing wave and insulating dielectric strength between the insulating layer and the inner conductor.

A wind powered turbine is disclosed that comprises two concentric cylinders. The first cylinder is located within the perimeter of the second cylinder. Both the first cylinder and the second cylinder comprise a plurality of blades. The first cylinder and its blades move in response to wind activity. The second cylinder and its blades do not move when the first cylinder and its blades are moving. The curvature of the blades of the first cylinder and the curvature of the blades of the second cylinder are in different directions with respect to each other.

The invention discloses an annular plate-containing concentric cylinder wave diffraction hydrodynamic force evaluation method, an annular plate-containing concentric cylinder comprises an inner cylinder, an outer cylinder and a perforated annular plate arranged between the inner cylinder and the outer cylinder, the method is characterized by comprising the following steps: establishing a cylindrical coordinate system at the intersection point of a still water surface and the center of the cylinder, and the z axis is vertically upward; the drainage basin is divided, the outer area of the outer cylinder is set as the outer area, the annular space area between the inner cylinder and the outer cylinder is set as the inner area, and the inner area comprises the area above the annular plate and the area below the annular plate; setting an opening boundary condition, defining a porous effect parameter of the opening annular plate as sum, and setting a related speed potential boundary condition; deriving an outer domain velocity potential and an inner domain velocity potential, and coupling velocity potential solutions through inner and outer domain boundary conditions; and solving the hydrodynamic load and the free surface elevation according to the velocity potential. The invention provides a wave diffraction hydrodynamic force evaluation method without a plurality of characteristic roots for a concentric cylinder structure containing a single-layer horizontal perforated ring plate. According to the method, the inner domain is further divided into two drainage basins, so that the trouble of a plurality of feature roots is avoided, a brand new feature function is established, and the solving efficiency can be greatly improved.

The utility model discloses a vertical radial flow regenerator which comprises a vertically arranged shell, a concentric cylinder is arranged in the shell in a hanging mode, the concentric cylinder and the shell are concentrically arranged, and the concentric cylinder comprises two cylinders which are spaced by a certain distance. The concentric cylinder divides the inner space of the shell into a sub-runner, a filling layer and a collecting channel which are sequentially arranged from outside to inside along the radial direction of the shell, and a buffer cavity communicated with the sub-runner is formed between the bottom of the concentric cylinder and the bottom of the shell; the filling layer is respectively and radially communicated with the branch flow channel and the collecting flow channel; the filling layer is filled with an energy storage medium for forming a bed layer and is provided with a packing seal which is positioned at the top of the energy storage medium and is used for preventing airflow short circuit after the energy storage medium settles; and a flow guide cone of which the diameter is gradually reduced along the axial direction is arranged in the branch flow channel or the flow collecting channel. According to the utility model, the bed resistance is smaller, the airflow distribution is more uniform, the space effective utilization rate and the energy storage performance are improved, and the large-scale development of the regenerator is facilitated.

The invention discloses a spiral-flow type riser reactor with an annular space structure. The reactor sequentially comprises a feeding section, a reaction section and a reaction stopping section from bottom to top, and the three sections respectively adopt a concentric cylindrical barrel, a concentric conical barrel and a hollow straight barrel. Raw material and catalyst feeding pipes are both positioned at the feeding section and are tangent to the outer cylinder body according to the same rotating direction, and rotational flow is generated in an annular gap between the inner cylinder and the outer cylinder. The catalytic cracking device is mainly used for preparing low-carbon olefin by taking heavy oil, wax oil, low-carbon alkane gas and the like as raw materials. According to the spiral-flow type riser reactor disclosed by the invention, raw materials and a catalyst can be uniformly mixed, and backmixing is basically eliminated; and a relatively large catalyst-oil ratio and strict reaction time can be adopted, so that the process conditions required for producing low-carbon olefins by catalytic cracking can be met, and compared with the conventional hollow cyclone reactor, the hollow cyclone reactor has obvious advantages.

The present invention provides a flexible sheet of broadband wave-absorbing metamaterial based on carbon-based materials. The sheet comprises a reflective layer and a dielectric layer embedded with periodically arranged structural units. The dielectric layer is arranged above the reflective layer. The preparation of the sheet comprises the following steps: the dielectric layer is arranged according to the size of the periodic resonant structural unit, and every other unit cell is arranged. P The size of the double-layer concentric cylindrical hole is mechanically punched; the small hole side of the medium plate with the hole is cleaned with anhydrous ethanol, and the reflective layer is applied; the graphene or carbon nanotubes are mixed with the adhesive to form a carbon composite for use; the graphene or carbon nanotubes are filled into the periodically arranged holes in step 1 with a scraper; the carbon composite is dried naturally until it is completely dry. The flexible sheet of this patent achieves a wide-band wave absorption effect in the range of 2 to 18 GHz, has a simple manufacturing process, is easy to use, can be applied to the object to be measured, and effectively reduces the characteristic signal of the radar wave of the target object.

The invention discloses high-thermal-conductivity fiber toughened fluorescent ceramic as well as a preparation method and application thereof, and aims to solve the problems of brittle fracture and thermal quenching of traditional fluorescent ceramic. According to the method, a pre-strain programmable 4D printing technology is adopted, and aluminum nitride (AlN) short fibers and carboxymethyl cellulose are self-assembled to form a natural concentric cylinder microstructure, so that the toughness and the mechanical property of the ceramic are enhanced. The strain distribution of the rubber film in a tensile state is simulated through finite element analysis, and the stress direction and the deformation control of a key area are optimized. Pre-strain is applied to the rubber film, and a fluorescent ceramic biscuit is printed on the surface of the rubber film; after the stress is released, the ceramic body spontaneously deforms into a hollow hemispherical structure. A rubber substrate is removed through high-temperature sintering, and the fluorescent ceramic with high mechanical strength and high thermal conductivity is obtained. The bending strength of the fiber-toughened fluorescent ceramic reaches 500-600 MPa, and the fracture toughness is improved to 9-11 MPa.m / , so that the fiber-toughened fluorescent ceramic is obviously superior to the traditional fluorescent ceramic.

The invention relates to the technical field of alloy casting, in particular to a magnetic particle reinforced alloy electromagnetic centrifugal casting system and a working method thereof. The electromagnetic centrifugal casting system comprises an electromagnetic centrifugal casting device, a driving device, an electromagnetic device and a vacuum device. The electromagnetic centrifugal casting device comprises a shell and a concentric cylindrical mold, the concentric cylindrical mold is rotationally installed in the shell and comprises an outer barrel and an inner barrel, the outer barrel is connected to the outer side of the inner barrel in a sleeving mode, a containing cavity is formed between the shell and the outer barrel, and a working cavity is formed between the outer barrel and the inner barrel; the driving device is used for driving the concentric cylindrical mold to rotate, the electromagnetic device is arranged in the containing cavity in a radioactive mode and used for generating a magnetic field, and the vacuum device is connected with the shell and used for vacuumizing. According to the invention, the problems of particle aggregation and uneven distribution in the traditional process are solved, and the mechanical property and production efficiency of the composite material are obviously improved.

A welding spatter protection device has a support structure, a movable structure delimiting a first internal cavity by internal side walls and movable by a first actuator between a lowered position, in which the first internal cavity is placed astride a welding zone, and a raised position, in which the first internal cavity is moved away from the welding zone, and a cleaning system having a scraper. Two second internal side walls interconnect two first internal side walls defining two concentric cylindrical surfaces. The scraper is connected to the movable structure by a support arm actuatable by a second actuator. Circumferential ends of the concentric cylindrical surfaces at an inlet mouth and at an internal stop position are radially aligned so that the scraper is always in contact with the concentric cylindrical surfaces, oriented so that a radially outermost cylindrical surface extends beyond the bottom wall, defining a shielding appendage.

The utility model discloses a kind of energy storage systems, specifically in the energy storage technical field, including spherical water tank, spherical water tank is equipped with vortex heat exchanger, the inner end of vortex heat exchanger is communicated with connecting pipe, and another end of connecting pipe is communicated with the top of spherical water tank, the top of spherical water tank is penetrated with first conveying pipe, the top of first conveying pipe is communicated with first concentric cylinder, and first conveying pipe and the center tube of first concentric cylinder are directly communicated, first concentric cylinder is equipped with heat absorption tower shell, the top opening of heat absorption tower shell is inserted with second concentric cylinder, first concentric cylinder and second concentric cylinder are staggered and inserted and form flow channel by heat absorption tower shell axial flow to heat absorption tower shell side wall, first concentric cylinder is fixedly connected with heat absorption tower shell by skirt with bottom setting through-hole, the outer end of vortex heat exchanger is communicated with second conveying pipe, and second conveying pipe is communicated with the bottom of heat absorption tower shell, and the energy storage system is under the common heat preservation of heat preservation soil layer and heat preservation layer in soil, hot water can be heat preserved for several days.

An actuating device 12 for actuating a clutch device 30 is provided, comprising a concentric slave cylinder 13, which has an annular piston 15 and an annular housing 14, wherein the annular piston 15 is axially movably received in an annular space 31 of the annular housing 14 which revolves around the main axis 100 and limits the annular space 31 axially with respect to the main axis 100, so that a pressure chamber 16 which can be filled with a hydraulic fluid is formed between the annular piston 15 and the annular housing 14, and comprising a housing section 18, wherein the annular housing 14 is received in the housing section 18 and an intermediate pressure chamber 16 which revolves around the axis of rotation 100 is formed radially between the annular housing 14 and the housing section 18.which is fluidically connected on the one hand to the pressure chamber 16 via at least one fluid opening 17 formed in the annular housing 14 and on the other hand to a pressure connection 21 via a pressure connection opening 20 formed in the housing section 16, wherein a hydraulic brake 44 is formed between the pressure connection 21 and the pressure chamber 16 to increase a flow resistance in the intermediate pressure chamber 19, which slows down a pulsating flow of a hydraulic fluid displaced by the annular piston 15 when the annular piston 15 moves.

An apparatus fixed to a water vehicle to produce electric energy has a turbine rotor supported under the water surface in a horizontal operation position and to it fixed first axis to transfer the rotation motion from the rotor and in which apparatus the rotor has been supported and adapted into with it same centered cylinder that has been fixed to the frame with vertically to it fixed joint that is situated a vertical distance (a) from the rotor and adapted to turn in relation to the frame that has been fixed to the water vehicle round the joint axis and to settle into the direction of the water flow by its power and where the first part of the second axis has been adapted same centered with the joint axis and the first and the second axis have been connected to each other with a rotation movement direction changer when the horizontal rotation of the first axis has been adapted to change into a vertical rotation movement in the first part and the second axis has been connected to a generator to transfer the rotation movement into it and the generator has been connected to a battery to store the generated electric energy to it.

1. Name of the design product: Main body of an electric nail care device. 2. Use of the design product: This design product is used for nail care. 3. Design key points of the design product: Lies in the shape. 4. Picture or photo that best shows the design key points: Combined perspective view. 5. The nail care device of Component 1 of this design product is cylindrical, with a tip at one end and connected to the power cord at the other end. The nail care device is composed of a concentric cylinder and a cone, and the radius of the cone gradually decreases from the power cord connection to the tip. Other views of Component 1 are omitted. 6. Other circumstances that need to be explained - Component description: This design product is a component product. Among them, Component 1 is the nail care device; Component 2 is the control box, which is connected to the nail care device via the power cord and is used to control the operation of the nail care device. 7. Other circumstances that need to be explained - Other explanations: The design protected by this application is a partial design. Among them, the solid lines indicate the parts that are claimed, and the dashed lines indicate the parts that are not claimed. The power cord in Component 1 of this design product is a slender item, and the two parallel double-dashed lines therein indicate the omitted parts.

The invention relates to a magnetic device (11) configured to generate a homogeneous magnetic field B in a specific zone (115), the magnetic field B having spatial components Bx, By and Bz along X, Y and Z axes of a Cartesian reference frame, said magnetic field 13 being adjustable in intensity ∥B∥ and three-dimensional spatial direction, the magnetic device (11) to be installed on additive manufacturing apparatuses enabling a magnetically-assisted 3D printing of composite elements, the magnetic device (11) comprising: ∘ an inner (111) and an outer (112) nested concentric Halbach cylinder arrays sharing a common revolution axis oriented along the Z-axis, each inner (111) and outer (112) Halbach cylinder arrays generating a homogeneous magnetic field of equal intensity B0, the inner (111) and outer (112) Halbach cylinder arrays allow generating a resulting magnetic field Bx,y (α, β) in the XY-plane, with spatial components Bx and By, the inner (111) and outer (112) Halbach cylinder arrays being mounted to rotate around their common revolution axis in order to achieve adjustability of both intensity and spatial direction of the resulting magnetic field Bx,y (α, β) in the XY-plane; ∘ a solenoid (113) positioned within a core of the inner Halbach cylinder array (111), and having a revolution axis aligned with the common revolution axis of the inner (111) and outer (112) Halbach cylinder arrays, the solenoid (113) generating and adjusting a magnetic field Bz of spatial component Bz along the Z-axis, the specific zone (115) being located in a core of the solenoid (113).

The utility model discloses an online injection device for preventing filler hardening in a blast furnace gas fine desulfurization system, which is characterized in that a reactor consists of a plurality of layers of concentric cylinders and is divided into an outer cylinder, a filler layer outer sieve plate and a filler layer inner sieve plate from outside to inside; the air supply source is connected with the supporting steel pipe; a plurality of supporting steel pipes are arranged on the outer side of the packing layer outer sieve plate and the inner side of the packing layer inner sieve plate in the circumferential direction at intervals and attached to the side walls of the packing layer inner sieve plate and the packing layer outer sieve plate. A plurality of short blowing pipes are vertically arranged on each supporting steel pipe at intervals, penetrate through the side wall of the outer sieve plate of the packing layer or the side wall of the inner sieve plate of the packing layer and extend into the packing layer. The supporting steel pipe is arranged in the filler layer, and the filler layer is inflated, so that the strength of the filler layer can be increased, nitrogen injection can be realized, the operation is simple, the problem of hardening of the filler in the tower body can be effectively solved, and the service life of the filler is prolonged.

The present invention relates to the technical field of friction and wear test, and particularly to a mating method and device for reciprocating friction and wear on a circumferential surface. The connection method of cross - crossed concentric cylinders is adopted to realize the installation of the specimen on the circumferential surface and a conventional testing machine, and then a friction pair is formed with a ring specimen or a disc specimen. When friction occurs, a reciprocating linear relative motion forms friction and wear. In the friction pair, the sample on the circumferential test surface is connected to the pin specimen fixture of the reciprocating friction testing machine through a cross - concentric adapter block and is clamped and fixed by a locking screw. The ring specimen or disc specimen for friction is connected to the testing machine by an installation table with a V - shaped positioning groove. Both the application of load and the reciprocating relative motion adopt the conventional reciprocating test method of the existing testing machine. The friction pair method and device of the present invention can solve the problem of evaluating the circumferential surface in the friction and wear test, ensure the smooth movement of the test process and the reliable contact of the specimen to be tested, and expand the application of the reciprocating friction and wear testing machine.

An actuating device 12 for actuating a clutch device 30 is provided, comprising a concentric slave cylinder 13, which has an annular piston 15 and an annular housing 14, wherein the annular piston 15 is axially movably received in an annular space 31 of the annular housing 14 which revolves around the main axis 100 and axially limits the annular space 31 with respect to the main axis 100, so that a pressure chamber 16 which can be filled with a hydraulic fluid is formed between the annular piston 15 and the annular housing 14, with a housing section 18, wherein the annular housing 14 is received in the housing section 18 and an intermediate pressure chamber 16 which revolves around the axis of rotation 100 is formed radially between the annular housing 14 and the housing section 18.which is fluidically connected on the one hand to the pressure chamber 16 via at least one fluid opening 17 formed in the annular housing 14 and on the other hand to a pressure connection 21 via a pressure connection channel 20 formed in the housing section 16; proposed, wherein the actuating device 12 has a damping device 44 arranged in the pressure connection channel 20, which is designed to dampen and / or eliminate a flow of hydraulic fluid displaced by the annular piston 15 that is at least temporarily pulsating during movement of the annular piston 15.

The utility model discloses a leakproof sealing structure of a pneumatic power mechanical element, which comprises an air cylinder, an air inlet and an air outlet, the air inlet and the air outlet are arranged on two sides of the air cylinder, a lower concentric cylinder is embedded and fixed in each of the air inlet and the air outlet, an upper concentric cylinder is in threaded connection with the lower concentric cylinder, a connector is fixedly connected onto the upper concentric cylinder, and the connector is in threaded connection with the lower concentric cylinder. A clamping plate is connected to the side of the connector in a clamped mode, a locking screw rod is connected to the surface of the clamping plate in an inserted mode, an air pipe is fixedly connected to the connector, and a throttling valve and an electromagnetic valve are arranged on the air pipe. The upper cylinder and the lower cylinder which are concentric are arranged at the air inlet and the air outlet of the air cylinder, air can be prevented from leaking from the air inlet and the air outlet of the pipeline and the air cylinder, meanwhile, the clamping plate and the locking screw are arranged at the pipeline connector, the connector for fixing the pipeline can be further reinforced, the problem that the connector shakes under the impact of the air is solved, and the service life of the air cylinder is prolonged. Therefore, the pneumatic power mechanical element has the leakproof sealing effect.

The invention provides a graphite core column for high-temperature and high-pressure synthesis of high-thermal-conductivity diamond and a preparation method, the graphite core column is of a three-layer concentric cylinder structure, and the graphite core column is sequentially composed of a nitrogen removal core layer, a catalytic reaction layer and a sealing pipe layer from inside to outside. The nitrogen removal core layer forms an active defense system, Ti / Zr elements located in the core react with nitrogen to produce stable nitrides, nitrogen impurities are firmly captured and fixed to the nitrogen removal core layer, and the diamond growth environment of the catalytic reaction layer is purified; and the catalytic reaction layer is formed by mixing a Ni-Mn-Cu ternary catalyst and graphite. The catalyst system ensures that the dynamic processes of dissolution and precipitation of the carbon source in the catalyst are consistent, and stable growth of diamond single crystals is facilitated; the outer-layer sealing pipe graphite is used for sealing an internal reaction system and preventing external pollution. The three layers of structures perform their own functions and cooperate with one another, impurity removal, growth and pressure maintaining are integrally designed, and the system solves the three core problems of nitrogen pollution, uneven growth and pressure fluctuation in synthesis of the high-thermal-conductivity diamond.

This invention relates to the field of angular contact ball bearing processing technology, and more particularly to a high-precision assembly fixture specifically designed for angular contact ball bearings. It includes an assembly box, an inner cylinder positioning assembly, an outer cylinder positioning assembly, and a temperature-conducting assembly. This invention utilizes the principle that semiconductor materials absorb and release heat at their two ends when energized, and, in conjunction with the lifting and rotating of the temperature-conducting assembly with a concentric cylinder structure, achieves flexible switching between cooling and heating. By attaching the heating / cold ends of the temperature-conducting assembly to the temperature-conducting platform, the temperature of the angular contact ball bearing is specifically adjusted, and the principle of thermal expansion and contraction is used to control the installation space. During assembly, the inner and outer cylinder positioning assemblies, working together, not only fix and limit the inner and outer cylinders respectively, but also automatically complete the installation of the balls. The installation methods are diverse, the process is highly controllable and automated, and it meets the high-precision requirements of different types of angular contact ball bearings.

A one-way valve seat is connected in a concentric cylinder gland in the horizontal direction through threads, a one-way valve is horizontally arranged in a stepped hole formed in the small end of the one-way valve seat, and a second sealing ring is arranged between the end face of the small end of the one-way valve seat and the concentric cylinder gland. A first sealing ring is arranged between the end face of the large end of the one-way valve seat and the concentric cylinder gland. The check valve is reasonable in structure and reliable in performance, other parts do not need to be detached when the valve element and the check valve seat are replaced, installation and detachment are quite rapid and convenient, maintenance efficiency is greatly improved, and maintenance cost is reduced.

The utility model discloses an energy-saving type heating network heater, and particularly relates to the technical field of heating network heaters, the energy-saving type heating network heater comprises a tank body, a hollow end cover is installed at an opening of the tank body, and a fixed concentric cylinder and a movable concentric cylinder are inserted in a staggered mode to divide an inner cavity of the tank body into a reciprocating zigzag flow channel extending from the axis to the annular outer wall; a plurality of heat exchange pipes extending in the same direction as the reciprocating zigzag flow channel are installed in the reciprocating zigzag flow channel, one ends of the heat exchange pipes jointly penetrate through the hollow end cover and jointly communicate with an integrated ring, the other ends of the heat exchange pipes jointly communicate with an integrated plug, a separator is fixedly embedded in the tank body, and the integrated plug communicates with an inner cavity of the separator; according to the heat exchanger, the flowing distance of a heating medium in a shell pass is prolonged, and meanwhile, the heat exchange efficiency is high when the heating medium and cold water oppositely flow in the tank body.

Broad volumetric range pipettes with multi-tiered pipette tip holder and ejection assemblies and methods of using such pipettes are disclosed herein. These pipettes typically include a concentric cylinder arrangement with each outer cylinder configured for contacting and dislodging a pipette tip attached to the tip holder portion of the immediately adjacent inner cylinder. In this manner, different sized pipette tips can be used on a single device. In addition, a locking mechanism is described for locking the large tip holder into a downward position to minimize the extension of the small tip holder and thereby enabling attachment of large, filtered pipette tips and reducing / eliminating the risk that the liquid being transferred will contaminate the pipetting device.

A gas-generating device drug column sealing end cap and sealing device, the sealing end cap comprises a circular cover plate, a three-layer cylinder standing on the inner surface of the circular cover plate, the three-layer cylinder is a concentric cylinder extending axially inward from the inner surface of the circular cover plate, and the three-layer cylinder comprises an outer cylinder, an inner cylinder and a center cylinder; a positioning cavity 1 for positioning the end of the outer tube is formed between the inner wall of the outer cylinder and the outer wall of the inner cylinder, the inner surface of the circular cover plate between the inner wall of the outer cylinder and the outer wall of the inner cylinder is the bottom surface of the positioning cavity; a positioning cavity 2 for positioning the end of the center tube is formed between the center cylinder and the inner circle of the circular cover plate. The sealing end cap can completely cover the edge of the outer tube to avoid drug leakage at both ends of the drug column, greatly reducing the safety hazards caused by drug leakage during production and transportation, and also improving the waterproof function of the drug column; the end cap and the outer tube are tightly assembled without the need for the process of tape sealing, thereby improving the production efficiency of the gas-generating device.

A wind powered turbine is disclosed that comprises two concentric cylinders. The first cylinder is located within the perimeter of the second cylinder. Both the first cylinder and the second cylinder comprise a plurality of blades. The first cylinder and its blades move in response to wind activity. The second cylinder and its blades do not move when the first cylinder and its blades are moving. The curvature of the blades of the first cylinder and the curvature of the blades of the second cylinder are in different directions with respect to each other.

The present invention belongs to the field of wireless communication, and more specifically, relates to a low-loss leaky coaxial cable and a manufacturing method thereof. The leaky coaxial cable includes an inner conductor, a composite insulation layer, an outer conductor, and a sheath layer coaxially arranged in sequence, and each layer forms a concentric cylindrical structure centered on the axis. By roughening the outer surface of the inner conductor and the outer surface of the outer conductor of the leaky coaxial cable respectively, the contact between the inner conductor and the insulation layer and the contact between the outer conductor and the sheath layer are improved. At the same time, the solid inner skin layer originally used for bonding the inner conductor and the insulation layer is omitted, which not only improves the signal transmission performance but also reduces the transmission loss. Compared with existing products, the leaky coaxial cable with the inner and outer conductor surfaces treated in the present invention optimizes the attenuation index by 2.6% to 5.8% in the multi-frequency band from 900 MHz to 2700 MHz on the premise of meeting the requirements of the adhesion between the insulation layer and the inner conductor, the standing wave, and the insulation dielectric strength test.

The invention provides a high-strength flame-retardant composite insulator device. The high-strength flame-retardant composite insulator device comprises a gradient functional composite core rod, an umbrella skirt group, an upper-end fitting and a lower-end fitting, the composite core rod with the gradient function is of a three-layer concentric cylinder structure and comprises an inner layer, a middle layer and an outer layer. The inner layer is formed by compounding E-glass fibers and epoxy resin; the middle layer is an epoxy resin matrix, and phase change microcapsules are uniformly dispersed in the middle layer; the outer layer is an epoxy resin matrix doped with a mixed filler of graphene and boron nitride; the gradient functional composite core rod is of a three-layer concentric structure, the inner layer is E-glass fiber / epoxy resin, and high tensile strength is guaranteed; the middle layer contains phase change microcapsules, so that heat energy absorption and temperature control buffering are realized; the outer layer is doped with the graphene and boron nitride mixed filler, so that the composite insulator has high thermal conductivity and intrinsic flame retardance, combustion is effectively inhibited, heat dissipation is accelerated, and the contradiction that a traditional insulator is not flame-retardant if being strong and is weak in flame retardance if being strong is solved.

The application discloses a kind of simulation near wellbore radial layered permeability loss combined formation physical model and preparation method thereof.The method uses sand type 3D printing technology, with furan resin and amorphous silica sand as raw material, and is integrally formed to prepare combined formation model containing prefabricated wellbore structure, which is composed of inner / middle / outer three independent concentric cylinder structures, realizes the simulation of permeability loss of each part of formation by vacuum permeation modifier post-processing.The inner / middle / outer three independent concentric cylinder structures are 3D printed according to the designed inner and outer diameter size, and to ensure the smooth assembly of three parts of structure, the inner diameter size of each part of structure is designed to reserve 0.5-1mm deformation redundancy (deformation joint).In the vacuum permeation post-processing process, nanometer silicon dioxide solution is used as modifier, vacuum saturation device is used for vacuum permeation treatment of component, and by changing the negative pressure holding time (5-10min) of each cycle and the vacuum saturation cycle number of each component, the independent and quantitative control of permeability of different structure layers is realized, so as to obtain the combined formation model with radial layered permeability difference from wellbore outward.The method can accurately and quantitatively prepare simulation near wellbore formation radial heterogeneous permeability loss, and has the advantages of flexible operation, low cost and strong controllability, which can provide reliable model preparation method for physical simulation of oil and gas reservoir development and underground pollutant migration.

Device for mechanical separation of distillate fractions has for a novelty a rotating vessel (104) mounted concentrically with a vertical pipe (102), between an overflow ring (103) and a segmented collector vessel (105), wherin the rotating vessel (104) contains two concentric cylindrical walls and a bottom in the form of a circular ring connected to a distillate outlet (109). The rotating vessel (104) can rotate around the vertical tube (102) axis. The collector vessel (105) is located below the rotating vessel (104), and fixed to the vertical pipe (102) and consists of several segments separated by partition walls (108), where each segment has an independent distillate drain (109) which is connected to the storage tanks. The device also includes an inlet (101), the overflow ring (103) and a discharge valve (110). The distillate is fed into the vertical tube (102), where it is raised and poured over the overflow ring (103), and then collected in the rotating vessel (104) which direct the liquid to the corresponding segment of the collector vessel (105).