36 results about "Slip velocity" patented technology

The invention discloses a system and a method for testing an all-weather tyre tread-road surface frictional characteristic. The test system comprises a console, a speed adjusting motor, a rotary disk, a pressure disk, a hydraulic loading cylinder, a vertical pressure sensor, a tyre tread test block, an environmental chamber, an environment control unit, a horizontal pulling and pressing sensor, a frictional road surface and the like; with the adoption of the system, the friction coefficient measurement between the all-weather rubber tyre tread and road surface covering the change ranges of use working conditions (including various different contact pressures, ambient temperature and humidity, slip velocity and road surface condition) of an automobile tyre can be realized, and an effective technological means can be provided for obtaining a curve of friction coefficient-slip velocity of rubber materials. Combined with the disclosed test system, a test method with short-time contact measurement is adopted in the invention to greatly reduce the influence on the libratory result due to rubber abrasion and temperature rising in the rubber friction coefficient test, and the repeatability and accuracy of the libratory result are remarkably improved.

The present invention provides a friction transmission belt having a friction transmission surface having a rubber composition containing a plasticizer, the plasticizer forming a film on the friction transmission surface, a change in friction coefficient (μ) with respect to a change in slipping velocity (V) indicated by a difference between a pulley speed and a belt speed (dμ/dv) being 0 or a positive value in a dry state and a wet state.

The invention discloses a high-rise building urgent safety escape device which comprises a main escape track installed on the outer wall of a high-rise building and a plurality of cassette mechanisms of the escape device, wherein, the main escape track is divided into a plurality of escape branch tracks that are installed on all the floors, and the cassette mechanisms of the escape device can slide on the escape branch tracks and the main escape track and can utilize friction force to adjust the sliding speed; each of the cassette mechanisms of the escape device is provided with a hitching hole of the cassette mechanism which is connected with safety escape clothes that can be rapidly worn in a detachable way; by using the escape tracks, the people can directly slide down to the bottom of the building from the places such as a balcony, a window or the like of each floor, and the departure time is short; as the escape tracks are arranged on the outer wall of the building, the people are prevented from being affected by smoke and dropping matters when in emergency and can safely escape; the cassette mechanisms of the escape device is provided with brake sheets which can control the slip velocity, and a damping spring used for reducing the slip impact is arranged at the end of the bottom of the main escape track, thus being fast and safe in evacuation.

The present invention is related to a numerical simulation method for the flight-icing of helicopter rotary-wings. This invention includes the algorithm of adding the voracity compensation force term to the momentum and energy equations describing the air-supercooled water droplets two-phase rotational flows in the single fluid two-phase flow system in wake domain of helicopter-rotary wings; the algorithm of adding the centrifugal and Coriolis force to the slip velocity equation; the models describing the water film and icing progress containing the effect of the centrifugal and Coriolis force; and the procedure using the above algorithms and models to do simulation.

Aiming at the worldwide problem for the early warning of the railway landslide hazard, in combination with the railway safe running and maintaining requirement, and synthetically using the geology, atmosphere, hydrology and electronic information technologies, the invention provides a three-level early warning method which decomposes the complex problem of the early warning of the railway landslide hazard into three levels of simple problems which are independent from one another such as tendency forecast, slip velocity forecast and accurate alarm and synthetically early warns by the monitoring of a rain gauge, a pull rope displacement sensor and a pressure sensor, wherein the method early warns (or monitors) the three levels such as the whole tendency of the happening of the landslide, the previous status which threats a line, and the precise moment which endangers the railway after the happening of the landslide, so that the three-level five-grade early warning solution which is suitable for the railway can be designed and realized, the exact, effective and practical early warning monitoring system for the railway landslide hazard can be formed, and various suggestions can be provided aiming at the using mode of the railway; and therefore, the invention is suitable for the landslide dangerous point sections along the railway, and the aim of effective early warning and monitoring of the railway landslide hazard can be achieved.

The invention discloses an adhesion control system for a motor train unit. A system for determining slip velocity of a wheel set of the motor train unit is used for carrying out information fusion and reconstruction on obtained wheel set linear velocity, train body velocity and train body accelerated velocity through an improved Sage-Husa self-adaptive Kalman filtering algorithm, judging the train body velocity, the train body accelerated velocity and the wheel set linear velocity, filtering electromagnetic interference of a sensor signal and uncertain mechanical interference through online estimation of measurement noises, obtaining accurate filtered train body velocity and using the filtered train body velocity as a reference velocity for calculating the slip velocity. The adhesion control system for the motor train unit, disclosed by the invention, is advantaged in that the system is conductive to a motor train unit control method using the slip velocity as an important parameter; and the control effect is improved.

The invention discloses a probe of measuring a gas-solid two-phase flow particle slip velocity. The probe comprises an optical imaging unit, a hot film velocity measuring unit and a light source transmission unit. An optical fiber imaging unit comprises an endoscope objective lens, a reflecting cover, a glass plain sheet and a silica fiber. The hot film velocity measuring unit comprises a hot film sensor and a microcircuit. The hot film sensor is arranged in a periphery of the glass plain sheet. The microcircuit is arranged in a reserved pipeline. The light source transmission unit comprises a laser light emitting port and glass optical fibers. The laser light emitting port is arranged in the periphery of the glass plain sheet of a probe head end portion. The glass optical fibers are uniformly arranged on a wall surface of an outer side of a stainless steel pipe. By using the probe in the invention, optical fiber imaging, hot film velocity measuring and light source transmission are integrated into one body; a gas velocity and a particle velocity in a gas-solid two-phase flow can be simultaneously measured; and a difference value of the gas velocity and the particle velocity is used to acquire a particle slip velocity.

A desalinating system and method is disclosed. The desalination system comprises using a turbo freeze or fast-cooling process to freeze saline water droplets and separate salt crystals from pure water crystals, wherein said system provides for simultaneous injection of saline water droplets and a chilled refrigerant into a freezing chamber at a slip velocity sufficient to reduce the size of the saline water droplets to an optimal diameter.

The invention discloses a life-saving landing apparatus, and relates to the technical field of architectural design and firefighting facilities. The life-saving landing apparatus is mainly and technically characterized in that the point of a pair of pliers is bent into 90 DEG, and the handle of the pliers is three times longer than the point of the pliers; B-shaped upper buckle collars are hung on double hooks; and after the weight of a person is loaded, a semicircular hole of the point of the pliers clamps a multistrand rope, and the escape person holds the handle of the pliers tightly or loosely by two hands to control the slip velocity of the life-saving landing apparatus so as to land safely. The invention provides a life-saving landing apparatus which has the advantages of safe escape and convenient use.

A device for measuring slip velocity under micro-scale comprises a trace gas pump, a barometer, a microinjection pump, liquid, a rectangular channel, a high-speed camera system and a water tank which are connected through relations, the left side wall of the rectangular channel is a hydrophilic silicon wafer I, the right side of the rectangular channel is formed by splicing two pieces of silicon wafers, the lower side of the rectangular channel is a hydrophilic silicon wafer III, the upper side of the rectangular channel is a hydrophilic silicon wafer II, and the front side and the rear side of the rectangular channel are transparent glass sheets; the trace gas pump sends trace gas into the rectangular channel, the microinjection pump injects a liquid column into the rectangular channel, the high-speed camera system performs camera shooting on the inside of the channel, analysis processing is performed on a shot image, the distances between the two positions of the movement of the liquid column and the contact points of the silicone wafer I and the silicone wafer II, and the movement time are measured respectively, the velocities of the liquid column on the surfaces of the two silicone wafers are obtained by dividing displacement by time, and the velocity difference on the two silicone wafers is the slip velocity of the liquid column on the silicone wafer II. The device for measuring the slip velocity under micro-scale has the advantages that an experiment is convenient to implement, post processing is simple, and experimental results are clear and easy to comprehend; repeatability is good; the device for measuring the slip velocity under micro-scale is applicable to micro-fluid systems.

The invention discloses an inverse design method for an electroosmosis microfluid electrode layout. The method comprises the following steps: step S1, in continuous medium hypothesis, using a Navier-Stokes equation to describe microfluid movement; step S2, based on that a Helmholtz-Smoluchowski theory is suitable for an electroosmosis microchannel inner wall, obtaining that slip velocity being indirect proportion to a tangential component of electric field intensity caused by an electrode; step S3, introducing a defected boundary condition on an entrance of the electroosmosis microfluid; stepS4, a side wall boundary [tau]w being divided into two parts, [tau]wa and [tau]de, a boundary condition of the[tau]de being interpolation of electric insulation and potential; step S5, using Helmholtz to filter a design variable, to control a feature size of a layout; step S6, using a threshold method to project the filtered design variable, eliminating values between 0 and 1, and deriving a physical density variable; step S7, through solving a variational problem, obtaining 0-1 distribution of physical density, to obtain an electrode layout on the boundary [tau]de. The method overcomes limitation on existing electrode design, and has universality and flexibility.

The invention belongs to the field of measurement of flow velocities of fluids and particularly relates to a boundary slip test device with the controllable slip ratio. The device comprises a first friction element (11), a second friction element (17), a loading system and a microscope (29), wherein the first friction element (11) and the second friction element (17) are driven by a first motor (6) and a second motor (22) respectively; the loading system adjusts a load between the first friction element (11) and the second friction element (17) by adjusting the pressing force between the first friction element (11) and the second friction element (17); the microscope (29) is used for observing the thickness of an oil film between contact positions of the first friction element (11) and the second friction element (17). With adoption of the device, the slip velocity can be measured according to the light-interference principle and the H-D empirical formula, and meanwhile, the device is applicable to boundary slip tests under various working conditions.

The invention discloses a method and device used for detaching gold flakes and solid fragments, which is characterized in that: a transparent container is arranged in a sink, and a through hole is arranged on the cylindrical surface of the same circumference at the centre of the transparent container, and the outside of the through hole is sealed by a detachable jacket; a blender and a water pipe are respectively arranged on a support, and the stirring paddle at the lower end of the stirring paddle shaft is extended into the transparent container, and the water pipe is aligned with the upward side of the transparent container; the blending of gold flakes and solid fragments is put into the container, after adding water and stirring, the slip velocity of the gold flakes is slower than the substrate, and the solid fragments quickly sink at the bottom of the container, and the gold flakes are suspended in water and sink gradually; temporality by unclosing the jacket of the container sidewall, the gold flakes effuse from the hole of the container sidewall along with the water and enter the sink, and the solid fragments are left in the transparent container, and then the detaching object is achieved. The method and device used for detaching gold flakes and solid fragments has an advantage of detaching all type of gold flakes and solid fragments.

The invention discloses a method for calculating the slip velocity of particles in a pump based on a clean water internal flow. The method comprises the steps: measuring the movement track and speed distribution of particles of a two-phase flow in the pump through high-speed photographing; writing a high-speed two-phase flow high-speed photographing image processing program through MATLAB and C programming languages, and calculating the instantaneous relative speed of the particles in the pump; Carrying out the numerical calculation of the flowing condition of clean water in the pump through a CFD method, and obtaining the relative speed of a liquid point at a position where the particles are located; building a function relation of a particle w and liquid w according to Weibull distribution; building a particle speed calculation formula based on the speed of the liquid point; and building a calculation formula for the slip velocity of the particles in the pump according to the definition of the slip velocity of the particles. The method can achieve the more accurate calculation of the moving speed of the particles in the pump according to the clean water internal flow, solves the slip velocity of the particles in the pump based on the above, and achieves the effective evaluation and prediction of the conveying performances of particle mediums with different physical properties.

The invention discloses a numerical analysis method for slip of a rolling body of a retainer-free ball bearing, which comprises the following steps of: by taking the retainer-free ball bearing as an object, analyzing slip of the rolling body of the retainer-free ball bearing under different bearing loads and different bearing rotating speeds by establishing and solving a kinetic model of the rolling body of the retainer-free ball bearing; and the slipping phenomenon of the rolling body is determined. The problem that the slipping phenomenon of the rolling body cannot be judged due to the fact that the accurate rolling body slipping speed cannot be obtained through a test means at present is solved.

Degradation of a running wheel is detected without using a special sensor or the like. Degradation of a running wheel of a running vehicle that travels using the running wheel that is rotated by a running motor is detected. A difference between a velocity of the running wheel obtained based on a number of rotations of the running wheel and a ground speed of the running vehicle, is obtained as a slip velocity, and degradation of the running wheel is detected based on a fact that torque of the running motor and the slip velocity have passed through a predetermined abnormal range in a space comprising a torque component and a slip velocity component.

A friction transmission belt includes a belt body which transmits power to a pulley. In a relationship between a friction coefficient and a slipping speed which is a difference between a speed of the belt body and a speed of the pulley, when a slipping speed at which a maximum friction coefficient is indicated is defined as a first slipping speed, a friction coefficient when the slipping speed is increased from the first slipping speed to a second slipping speed is defined as a reference friction coefficient, and a difference between the second slipping speed and the first slipping speed is 500 mm/s, a decrease rate Dm of the friction coefficient indicated by the following equation (1) with the maximum friction coefficient being denoted by μx and the reference friction coefficient being denoted by μr is not greater than 20%.

Dm=(μx−μr)/μx×100  (1)