229 results about "Viscous resistance" patented technology

An automatic speed reducing ratio-switching apparatus comprising an input side carrier, an output side carrier, and an intermediate carrier includes first and second planetary gear mechanisms juxtaposed in the axial direction of an input shaft, first and second inner clutch members which are rotatable in one direction while locking rotation in the other direction of the input shaft, and have mutually different locking directions, first and second outer clutch members which are rotatable in one direction while locking rotation in the other direction of the input side or output side ring gear, and have mutually different locking directions, and a viscous resistance member functioning under a static frictional force to integrally rotate the input side or output side sun gear, the input side or output side planet gears, and the input side or output side ring gears respectively in an identical direction.

In a mobile robot, the actuator characteristics are dynamically or statically controlled, during motions of an entire robot body in the course of falldown or descent, to realize stable highly efficient motions. In each stage of the falldown motions, the characteristics of each joint site taking part in controlling the stable area are set so that the low range gain is low, the quantity of phase lead is large and the viscous resistance of the motor is large, in such a manner that these joint sites may be positioned to high accuracy in a controller manner to increase orientation stability. This assures the positioning accuracy of the joints as main component for controlling the quantity ΔS/Δt as a reference in controlling the falldown motions of the robot body to increase the motion stability.

The invention relates to a strong gas-wetting nanosilicon dioxide water block removal agent, a preparation method thereof and a method for wetting transition of rock surface. The modified nanosilicon dioxide water block removal agent comprises the following raw materials: 0.1-0.5% of modified nanosilicon dioxide, 0.5-1% of an emulsifying agent OP-10, 0.5-1% of lauryl sodium sulfate, 25-50% of ethyl alcohol and the balance of water; the nanosilicon dioxide modified treating fluid is 0.05-0.3% of a non-ionic fluorocarbon surfactant water solution. The invention further provides a preparation method and application of the modified nanosilicon dioxide water block removal agent. The modified nanosilicon dioxide material has a super-hydrophobic and super-oleophobic property, can be used for changing the liquid-wetting property of the rock surface into strong gas-wetting property, so as to reduce the viscous resistance of fluid flowing on the rock surface, improve the flowing status of fluid in a porous medium, remove water blocking damage, is used for low-permeability oil and gas field exploitation and increasing of the oil and gas recovery ratio.

An article includes a body having at least one viscous drag-reducing surface defining a multiplicity of macro-scale depressions separated and enframed by ridges, at least a portion of the surface being phobic to a preselected liquid so that gas bubbles may be trapped in the macro-scale depressions in order to reduce viscous drag between the article and the liquid.

The invention discloses a method for online calculation of a working fluid level of an oil well by using a pumping unit pump indicator diagram. The method for online calculation of the working fluid level of the oil well by using the pumping unit pump indicator diagram is characterized by comprising the following steps: a ground indicator diagram is obtained; a computer is used for mathematically processing to eliminate such influences as deformation of a pumping rod column, viscous resistance of the rod column, vibration and inertia to obtain an underground pump indicator diagram simple in shape and capable of truly reflecting pump working conditions; an underground pump indicator diagram model is built to calculate a fu's series solution and a viscous resistance coefficient v of the underground pump indicator diagram; and then, a curvature model is built according to the relationship between the obtained underground pump indicator diagram and a valve opening/closing point and the viscous resistance coefficient v to determine the valve opening/closing point.

A chain tensioner includes a cylindrical cylinder having a closed end, a plunger slidably mounted in the cylinder, and a return spring biasing the plunger. The cylinder is formed with an oil supply passage through which hydraulic oil is introduced into a pressure chamber defined by the plunger and the cylinder. The oil supply passage has an orifice at its end portion facing the pressure chamber. A leak gap is defined between sliding surfaces of the plunger and the cylinder. A damper force is produced by viscous resistance of hydraulic oil flowing from the pressure chamber through the leak gap, and by viscous resistance of hydraulic oil flowing from the pressure chamber into the oil supply passage through the orifice.

A method of computational fluid dynamic modelling of a subterranean region comprises: defining a computational domain by generating a geometrical model of a subterranean region comprising a wellbore and a surrounding formation; associating knowledge of a physical property of the subterranean region with a computational parameter; and inputting the computational parameter into the computational domain. In one embodiment knowledge of permeability within the subterranean region is defined as a viscous resistance within the computational domain.

A method and apparatus for producing soft x-ray laser radiation based on z-pinch compression of a rotating low pressure plasma column are disclosed. A rotating, low pressure plasma column is created by electric discharge or by laser excitation inside a containment tube. Rotation of the plasma may be induced by viscous drag caused by rotation of the tube, or by magnetically driven rotation of the plasma as it is created in a plasma gun in the presence of an axial magnetic field, or both. A high power electrical discharge is then passed axially through the rotating plasma column to produce a rapidly rising axial current, resulting in z-pinch compression of the rotating plasma column radially inwardly with resultant stimulated emission of soft x-ray radiation in the axial direction. A rotating containment tube used in combination with magnetically driven rotation of the plasma column results in a concave electron density profile that in turn results in reduced wall ablation and also reduced refraction losses of the resultant soft x-rays.

The invention discloses an opening type micro-fluidic chip, as well as a manufacture method and an operation method of the micro-fluidic chip. The opening type micro-fluidic chip comprises a chip substrate, wherein a super-smooth surface is formed on the chip substrate; the super-smooth surface is a liquid coating layer which is filled with a lubricant and formed by a surface with a sunk micro-structure. According to the opening type micro-fluidic chip, the super-smooth surface is adopted, the viscous resistance of exogenous substances moving on the surface of the micro-fluidic chip can be greatly reduced, and thus the driving mode of the exogenous substances, especially fluid, can be expanded, the operation flexibility can be improved, and a sensitive system can be operated and controlled.

A tapered roller bearing is designed to have a roller loading ratio in the range of 0.7 to 0.92 and a ratio of roller length to roller diameter in the range of 1.1 to 1.7 whereby oil agitation loss and rolling viscous resistance are reduced for achieving the reduction of running torque. Crownings are provided which are designed to have an outer-ring crowning parameter (=RCO/LRO) in the range of 30 to 150 and an inner-ring crowning parameter (=RCI/LRI) in the range of 50 to 260, provided that RCO denotes the radius of an outer ring crowning, LRO denotes the raceway length of an outer ring, RCI denotes the radius of an inner ring crowning and LRI denotes the raceway length of an inner ring. Thus, the rolling viscous resistance is reduced for achieving the reduction of running torque.

At four corners of a pressure plate 7, weights 15 are adhered an adhesive agent for high temperature use. When a frictional vibration is generated by frictionally engaging with a rotor in operating a brake, a shim 12 is displaced relative to a pressure plate 7 by inertia of the weight 14. Grease 13 between the shim 12 and the pressure plate 7 flows so as to produce a viscous resistance to a vibration of the shim 12 relative to the pressure plate 7. By the viscous resistance, the vibration of the pressure plate 7 is attenuated, as a result, brake squeal can be restrained from being brought about.

The invention provides an optical trapping based method for in-situ calibration of displacement of a piezoelectric platform. High-precision detection of motion displacement amplitude and frequency of the piezoelectric platform can be realized by analysis of position signals of Brownian motion of standard-size globules trapped in an optical trap system. Besides detection of the piezoelectric platform, standard particles are trapped by laser under microscopic imaging, and position motion signals of the particles are quickly detected by a detector. The piezoelectric platform sends low-frequency fixed-amplitude motion signals to drive a sample chamber to move, the particles trapped in a light trap is subjected to actions of fluid periodic viscous resistance, and voltage proportionality coefficient of a position sensitive detector can be calibrated by detecting the motion signals of the particles. The piezoelectric platform sends signals to drive the sampling chamber to move again, a power spectrum of the trapped particles is analyzed, a peak of the power spectrum is compared with background thermal noise to invert real motion displacement amplitude of the piezoelectric platform, and frequency of the peak stands for motion frequency of the piezoelectric platform.

A thermal inkjet printhead with heater elements disposed in respective bubble forming chambers for heating part of the ejectable liquid above its boiling point to form a gas bubble that causes the ejection of a drop of the ejectable liquid from the nozzle, wherein, the heater is separated from the nozzle by less than 5 μm at their closest points; the nozzle length is less than 5 μm; and the ejectable liquid has a viscosity less than 5 cP. The volume of liquid between the heater and the nozzle determines the inertia of the liquid and its acceleration in response to bubble formation. Moving the heater closer to the nozzle reduces the inertia of the liquid and increases its acceleration, so a lower bubble impulse is needed to eject a drop. This allows the printhead to use smaller heater elements with lower power requirements. Viscous drag in the nozzle reduces the momentum of fluid flowing through the nozzle. The viscous drag increases as the nozzle length (in the direction of fluid flow) increases. By reducing the nozzle length, a lower bubble impulse is needed to eject a drop. This also allows the printhead to use smaller heater elements with lower power requirements.

The present invention can effectively attenuate and absorb an auxiliary vibration even in the case that the auxiliary vibration input along a direction approximately orthogonal to a main vibration input along an axial direction of the apparatus, in addition that it is possible to effectively attenuate and absorb the main vibration while suppressing an engagement of a size of the apparatus. In a vibration proofing apparatus (210), two second pressure receiving liquid chambers (302A, 302B) are arranged between an outer tube (224) and a mounting attachment (226), and two second pressure receiving liquid chambers (302A, 302B) are communicated with an auxiliary liquid chamber (272) through two second orifices (308A, 308B). Accordingly, if an auxiliary vibration along an auxiliary amplitude direction orthogonal to an axial direction is input to the mounting attachment (226) from an engine side, a rubber elastic body (222) is elastically deformed along an auxiliary amplitude direction, and expands and contracts an internal volume of the second pressure receiving liquid chambers (302A, 302B), and the liquid circulates in the second pressure receiving liquid chambers (302A, 302B) and the auxiliary liquid chamber (72) with each other through the second orifices (308A, 308B). At this time, since a resonance phenomenon is generated in the liquid circulating between the second pressure receiving liquid chambers (302A, 302B) and the auxiliary liquid chamber (272) through the second orifices (308A, 308B) in synchronization with the input auxiliary vibration, it is possible to particularly effectively absorb a low-frequency vibration input along the auxiliary amplitude direction due to a pressure change, a viscous resistance and the like generated together with the resonance phenomenon of the liquid.

The invention discloses a rubber syringe needle protective cap for a pre-encapsulation injection syringe. The protective cap is prepared from the following raw materials in parts by weight: 100 parts of synthesized polyisoprene rubber, 5-30 parts of alkaline white carbon black, 20-70 parts of calcined kaolin, 0.3-1.2 parts of peroxide, 0.5-1.0 part of stearic acid, 5-20 parts of polytetrafluoroethylene micro powder, 5-20 parts of ultra-high molecular weight polyethylene micro powder, 1-5 parts of titanium dioxide and 1-3 parts of carbon black. The rubber syringe needle protective cap has the obvious characteristics that a clean and simple peroxide sulfuration system is adopted, and a conventional complicated sulfur and zinc oxide promotion system is avoided. Special alkaline fillers are adopted, the sulfuration degree and speed of rubber are improved, and a smell problem caused by adopting the peroxide to sulfurate the polyisoprene rubber is reduced. The polytetrafluoroethylene micro powder and the ultra-high molecular weight polyethylene micro powder with good inertness and dispersibility are added into a formula, the lubricity and chemical inertness of the rubber are improved, and the viscous resistance of a rubber syringe needle protective cap product is improved.

The invention discloses a method for controlling oil and gas well drilling to reduce drill string viscous resistance, and belongs to the field of the oil and gas well drilling technology. A top drive device (or rotating disc) is adopted to drive a drill string to rotate forwardly and reversely according to the set rotating manner; through mud-pulse signals, a tool face angle of a power motor, an azimuth angle and well deviation which are monitored by a directional sensor in an MWD and vertical pipe pump pressure are fed to a ground controller through the digital quantity signal mode and are matched with upper portion drill string torque monitored by the top drive (or rotating disc), and through the method that a top drive main shaft (or rotating disc square drill rod) is controlled to forwardly rotate or reversely rotate, the drill string is rotated forwardly or reversely, so that the tool angle face of the well drilling motor is changed, the azimuth angle and the well deviation are adjusted or corrected, and the drill string viscous resistance is reduced; the top drive main shaft is controlled to forwardly rotate by the set angle and the set number of turns, and after being in place, the top drive main shaft rotates reversely to the initial position, and forward cycling is formed. According to the method, influence of manual factors on well drilling work is reduced, and the drilling efficiency and the production safety are improved.

A simulation method of estimating performance of a product made of a viscoelastic material, comprising the steps of measuring a value of a strain, a strain speed, and a stress generated in viscoelastic material momently in a measuring condition equivalent to a state in which the product is actually used; deriving time history data of a viscosity resistance of the viscoelastic material separately in each of a strain increase state and a strain decrease state from time history data of the strain, the strain speed, and the stress and a viscoelastic model set in consideration of a viscosity of the viscoelastic material; setting the product as a product model whose performance is analyzed and inputting a relationship among the strain, the strain speed, and the viscosity resistance to the product model to conduct a simulation in consideration of a phenomenon that the viscosity resistance changes in dependence on a variation of the strain and the strain speed and in consideration of a difference in the viscosity resistance between a strain increase state and a strain decrease state.

The invention discloses a three-dimensional digital ship model virtual resistance test method and system, and belongs to the field of surface ship resistance performance experiments. The method comprises the following steps of (1) establishing digital ship models and flow field calculation domains where the digital ship models are located; (2) arranging full-structured hexahedral grids in the flowfield calculation domains around the digital ship models, and discretizing the flow field calculation domains; (3) setting boundary conditions, dividing the hexahedral grids to simulate the free surface movement and the non-free surface movement of the digital ship models, and respectively measuring a wave-making resistance coefficient and a viscous resistance coefficient of the digital ship models; (4) obtaining a total resistance coefficient of the ship and flow field information in the flow field calculation domains through the wave-making resistance coefficient and the viscous resistancecoefficient; and (5) carrying out fluid power analysis on the flow field information to obtain a ship free surface wave height distribution curve and a ship free surface wave-making distribution clouddiagram. The method and the system provided by the invention can provide reliable water power data and flow field information for the design and optimization of the ship.

The invention discloses a method and device for measuring the viscous resistance coefficient and the inertial resistance coefficient of a porous medium. The method comprises the following steps: 1, obtaining the pressure drop delta p of fluid before and after the fluid flows through the porous medium, and the flowing speed v of the fluid through the sensor; 2, carrying out the fitting of delta p and v in a quadratic polynomial: delta p=a<1>*v*v+a<2>*v, and obtaining the values of parameters a<1> and a<2>; 3, calculating the viscous resistance coefficient 1/alpha and the inertial resistance coefficient C2, wherein the viscous resistance coefficient 1/alpha and the inertial resistance coefficient C2 meets the formulas (shown in the description), delta n is the thickness of the material of the porous medium, mu is the dynamic viscosity of the fluid and Rho is the density of the fluid. The invention also provided a device for measuring the viscous resistance coefficient and the inertial resistance coefficient of the porous medium. The method can calculate the viscous resistance coefficient and the inertial resistance coefficient through measuring the flowing speed of the fluid and the pressure difference before and after the fluid flows through the porous medium, is simple, and is high in precision. The device for measuring the parameters is compact in structure, is low in cost, and is very convenient to use.