667results about How to "Realize online measurement" patented technology

A large multifunctional fracturing fluid experiment system is characterized in that a drug soup and a gas branch enter a foam generator and are mixed, the obtained mixture enters three straight pipes with different calibers, the influences of the calibers on the frictional resistance of the fracturing fluid are measured, or the soup enters a coil pipe in order to measure the frictional resistance, and two ends of each of the above four pipes are respectively connected with a differential pressure sensor; when the frictional resistance is measured, two ends of the four pipes are respectively provided with a valve; during experiment, the above valves can be switched, and one path can be selectively opened, the suspension state of a propping agent in the fracturing fluid can be observed through a multistage window, the obtained fracturing fluid enters a drug pump and is circulated in order to measure the frictional resistance; or the obtained fracturing fluid enters an outlet separator after the experiment. The system is used for measuring a jelly fracturing fluid, a clear water fracturing fluid and a carbon dioxide foam fracturing fluid, or can be used for researching the rheological characteristic, the frictional resistance and the sand carrying performance of a carbon dioxide dry fracturing fluid at different temperatures under different pressures, and can be used for observing the suspension state of the propping agent in the fracturing fluid through the multistage window.

The present invention provides one kind of system to perform distributive multi-point detection for corrosion, crack, leakage, wax precipitation, scaling and other status in long oil and gas conveying pipeline by means of fiber grating sensing technology. The system includes near-infrared wide-band semiconductor laser source array, wavelength division multiplexer, bi-directional fiber coupler, fiber grating sensor array, spectral analyzer and signal transmission optical cable. The continuous near-infrared light signal the laser source array emits is transmitted to fiber grating sensor array embedded inside the long oil and gas conveying pipeline through the wavelength division multiplexer and the bi-directional fiber coupler, the sensor array detects the varying temperature and pressure of fluid inside the pipeline and reflects to the bi-directional fiber coupler while being coupled to the analyzer and the computer to obtain the conveying status inside the pipeline.

Disclosed is an apparatus for measuring surface tension, density and wettability of a medium-low temperature fused mass, which relates to the technique field of fused mass property measurement. The apparatus comprises: a heating device (1), a transparent quartz furnace tube, a light source (8), a digital camera (11) and a computer (12); and the transparent quartz furnace tube is horizontally positioned in the heating device (1), and both ends of the transparent quartz furnace tube stretch out of the heating device by 10 to 15cm. The light source (8), the digital camera (11) and the transparent quartz furnace tube are positioned at the same horizontal line; and software installed on the computer (12) can realize the on-line connection with the digital camera (11), dynamic changes of melt drip contour can be displayed dynamically on a computer display directly, and photo taking and animation shooting can be controlled by the computer. The apparatus has the advantages of adjusting the level of base plate conveniently and accurately, improving the measuring precision and repeatability; good sealing, available selection of a plurality of atmospheres such as vacuum, air and high purity argon gas; realizable on-line measurement of thermal property such as surface tension; and low cost of manufacture and simple operation.

The invention discloses an online measuring method and an online measuring device for a micro-nano deep groove structure. The method comprises the following steps: linearly polarized infrared beams are projected to the surface of a sample piece which is provided with the deep groove structure, and measured reflection spectra are obtained after interference signals which are formed by reflected light on various interfaces of the groove structure are subjected to filtration and so on; an equivalent optical model of the deep groove structure is established by the polarization-based equivalent medium theory, and theoretic reflection spectra of the equivalent optical model of the deep groove structure are calculated; and the width and the depth of the groove are quickly extracted by the quick parameter extraction method of combination of an artificial neural network and a local search algorithm and through fitting of the theoretic reflection spectra and the measured reflection spectra, and precise online measurement of geometrical shape parameters of the deep groove is realized. The device comprises an infrared source, an infrared polaroid sheet, an interferometer, a plane mirror, two off-axis parabolic mirrors and an infrared detector. The device can realize online measurement of the depth and the width of the deep groove structure with high depth-width ratio in a field effect tube and a dynamic RAM during the manufacturing procedure, and has the characteristics of nondestructiveness, quickness and low cost.

The invention provides an ice shape contour measuring method based on three-dimensional ultrasonic imaging technology. The method can be used for an iced wind tunnel and in the airplane model icing experiment process, and is used for realizing 3D ice shape on-line measurement in the model icing growth process. The method is characterized by utilizing an ultrasonic probe to emit an ultrasonic signal, and meanwhile, receiving an echo signal and processing the echo signal to obtain a two-dimensional ultrasonic image; while collecting the echo signal and obtaining the two-dimensional ultrasonic image information, utilizing an electromagnetic positioning sensor to collect spatial position information of an icing model corresponding to the ultrasonic probe; and then, through coordinate transformation between an ultrasonic plane coordinate system and a world coordinate system, obtaining three-dimensional coordinate of a model to be measured, and realizing three-dimensional reconstruction of the wind tunnel model 3D ice shape. In order to observe the 3D ice shape in the model icing growth process, the invention adopts the three-dimensional ultrasonic imaging technology to obtain a three-dimensional ultrasonic image of the model ice shape. The invention provides a non-contact ice shape contour measuring method; and compared with several conventional iced wind tunnel measuring methods, the method can improve experiment efficiency and realize online measurement.

The invention discloses a flatness and parallelism measurement device and a flatness and parallelism measurement method. The flatness and parallelism measurement device comprises a working table. The working table is provided with a lower measurement base and vertical sliding rails located on the two sides of the lower measurement base. An upper measurement base is arranged above the lower measurement base, up-and-down sliding connection is formed by the upper measurement base and the vertical sliding rails, the upper measurement base and the lower measurement base are respectively provided with a plurality of first displacement sensors and a plurality of second displacement sensors, and the first displacement sensors and the second displacement sensors are annularly distributed around the same vertical surrounding center shaft at equal interval. When measurement is carried out, the zero values of the first displacement sensors and the zero values of the second displacement sensors are set through a standard verification block, then the coordinate value of each measured point of a workpiece is measured, a data processing system can conduct fitting to obtain the datum plane of the upper measurement face and the datum plane of the lower measurement face, the flatness error values of the upper measurement face and the lower measurement face of the workpiece can be further calculated, and the parallelism error value of the upper measurement face relative to the lower measurement face can be further calculated. According to the flatness and parallelism measurement device and the flatness and parallelism measurement method, the flatness and the parallelism can be measured at the same time, the measurement procedures are rapid, the measurement accuracy is high, and the flatness and parallelism measurement device and the flatness and parallelism measurement method are suitable for on-line measurement.

The invention provides an online automatic monitoring system of total nitrogen and total phosphorus in seawater and a monitoring method thereof. The system comprises an automatic seawater liquid feedcontroller, an ultraviolet microwave digestor, a total nitrogen measuring flow passage, a total phosphorus measuring flow passage and a spectrophotometer, wherein the automatic seawater liquid feed controller is connected with the ultraviolet microwave digestor by a liquid feed pipeline; digested sample flows into an electronic cooler from a liquor drainage pipeline of the ultraviolet microwave digestor to be cooled and respectively enters into the total nitrogen measuring flow passage and the total phosphorus measuring flow passage; the total nitrogen measuring flow passage comprises a nitrate ion reducing device, a sample reaction pipeline is connected with the spectrophotometer, and the front end of the sample reaction pipeline is provided with a nitrite color reagent injecting valve; and the total phosphorus measuring flow passage comprises the structure that the sample reaction pipeline is connected with the spectrophotometer, and the front end of the sample reaction pipeline is provided with an orthophosphate color reagent injecting valve. The invention can complete work procedures such as automatically sampling seawater, digesting, reducing, washing, measuring, and the like,at one time.

The invention relates to a method for on line detecting biological transmutation process of solid-state biomass, the steps of the method are as follows: choosing not more than 50 portions of samples of representative biomass in the biological transmutation process as standard samples for acquiring standard maps; obtaining the parameters on target process by other means; establishing a quantitative model through multiple regression to quantify other unknown processes. The method provided by the invention can realize on-line detection of parameters in biological transmutation process only by establishing a forecasting model and can automatically detect and control the biological transmutation process, without sample preparation or reagent consumption. The method is used for forecasting related coefficients in solid-state fermentation, including moisture content, biomass, grease output and cellulase, the forecast related coefficients respectively reach 0.994, 0.999, 0.984 and 0.994.

The invention discloses a method for measuring a high energy laser energy parameter based on a light pressure principle and an apparatus thereof. The method comprises the following steps: a reflector and a deformation rod are arranged on a high energy laser incidence optical path, a plurality of displacement sensors are provided at a back side of a reflector laser incidence direction, micrometricdisplacement of the reflector caused by light pressure in a laser light extraction process is measured in real time, a light pressure value generated by laser is solved, and parameters of the laser such as average power, energy, P-t curve, light spot center of mass change and the like are calculated. According to the method and the apparatus in the invention, light beam is not blocked in usage, an on-line measurement of undistributed transmission of high energy laser is realized, cost-effectiveness of an experiment is raised, simultaneously, a measurement system does not need to bear strong laser irradiation, and the method and the apparatus can be used for high power laser parameter measurement.

The invention discloses a device and a method for detecting sulfur trioxide (SO3) in flue gas on line. The device comprises a flue gas collecting unit, a gas liquid separator, a gas phase detection unit, a first solution tank, a liquid phase detection unit and a digital control unit, wherein the gas liquid separator is used for condensing SO3 in the flue gas from a flue gas sampling unit into sulfuric acid liquid drops and separating the sulfuric acid liquid dropsfrom gas phase; the gas phase detection unit is used for measuring the flow of the gas phase from the gas liquid separator; the first solution tank is used for providing an absorption liquid to the gas liquid separator and mixing the absorption liquid with the sulfuric acid liquid drops to form mixed liquid; the liquid phase detection unit is used for measuring the mass of the transformed SO3 in the mixed liquid from the gas liquid separator; and the digital control unit is used for calculating the SO3 concentration of the flue gas according to the detection results of the gas phase detection unit and the liquid phase detection unit. According to the device and the method, on-line measurement of the SO3 of the flue gas is realized, the SO3 of the flue gas is sampled and the SO3 content is analyzed, so that a coal-fired power plant can take corresponding measures conveniently, the SO3 content of the flue gas is controlled, the corrosion to a flue and equipment is reduced, and the heat loss due to exhaust smoke of a boiler is reduced to the maximum degree.

The invention discloses a quick phototyping by laser cladding layer height measuring device and a closed-loop control method thereof. The quick phototyping by laser cladding layer height measuring device comprises three laser 2D (two-dimensional) displacement sensors, a control unit, an upper computer and a display. According to the closed-loop control method, the three laser 2D displacement sensors are spaced at an included angle of 120 degrees and mounted around a cladding bit for measuring the height of the cladding layers on the side lines of a closed laser equilateral triangle around a molten metal bath; every laser 2D displacement sensor is provided with a sensor controller for converting CMOS (complementary metal-oxide-semiconductor) image signals into height data and transmitting the height data to a control unit via an Ethernet network; the control unit is used for processing the data collected by the three laser 2D displacement sensors, computing the height of cladding layer and feeding the height back to the upper computer; the display is used for in real time displaying the height date measured by the three laser 2D displacement sensors and the layer height data processed by the control unit. The quick phototyping by laser cladding layer height measuring device and the closed-loop control method thereof achieves real-time precise control of the single-layer lifting capacity of the cladding bit.

The invention discloses a friction wear testing machine for on-line measurement, which comprises an experiment table, a friction wear experiment device arranged on the experiment table and a surface topography measurement device. The friction wear testing machine is characterized in that the friction wear experiment device comprises a stress beam, and a support and a rotating platform which are arranged on the experiment table, the rotating platform fixes a lower specimen, and the support is positioned at one side of the rotating platform; the support is provided with a rotating shaft which is fixed with a walking beam, one end of the walking beam is fixed with a balance weight lever which is provided with a balancing weight, the other end of the walking beam is fixed at one end of the stress beam, the other end of the stress beam is fixed with a collet which is fixed with an upper specimen, and the collet is provided with a scale pan which is provided with weights; the stress beam is provided with a force sensor for measuring the friction force between the upper specimen and the lower specimen; and the surface topography measurement device comprises a three-coordinate adjustment table arranged on the experiment table, the three-coordinate adjustment table is provided with a surface contourgraph, and a probe of the surface contourgraph extends above the rotating platform.

The invention discloses an optimal control method for grinding and grading mineral powder, which is characterized in that: the grinding load and grinding concentration is obtained by sampling grinding-grading process signal, with the help of the advanced control and through testing the state in the grinder; the optimal grinding load, the optimal sand-returning ratio, the optimal grinding concentration and the optimal overflow concentration are obtained through the grinding load optimization, the sand-returning ratio optimization, the grinding concentration optimization and the overflow concentration optimization; the feeding quantity is obtained through the control algorithm of the feeding quantity ; the sand-returning water volume is obtained through the control algorithm of the sand-returning water volume; the discharging water volume is obtained through the control algorithm of the discharging water volume. The optimal control method has advantages that: the global optimization to the grinding-grading process is realized; and meanwhile the diagnosis is done to reveal the fault of the grinding-grading process; the appraisal and analysis is executed in the grinding-grading process; reasonable advice is come out; continuous, stable, safe and economic running is ensured; so the method is widely used in the grinding-grading process and similar wet milling process in other industry crafts.

The invention provides an application method for a travelling wave positioning system of a distributed high-precision electric transmission line. The method comprises the following steps: receiving power frequency failure current transmitted in an electric transmission line wire by an on-site testing device, performing analog-to-digital conversion to the power frequency failure current to obtain digital waveform signals, uplinking the digital waveform signals to an upper computer, and determining the accurate position of trouble spot by a supervisory system installed in the upper computer via calculation. The method remarkably reduces the travelling wave positioning error and improves the positioning accuracy.

The invention discloses a coal-fired boiler coal quality on-line soft measurement method and system. The coal-fired boiler coal quality on-line soft measurement method includes the steps of (S100) the contents of the as received basis ash content Aar, the dry ash-free basis elemental carbon Cdaf and the dry ash-free basis elemental sulphur Sdaf are assumed; (S200) the uncompleted burned carbon consumption correction amount TCucr, the oxygen volume VO2-daf, the nitrogenn volume VN2-daf and CO2 volume gamma CO2, CO2 and SO2 gross capacity VRO2-daf are calculated according to the contents; (S300) iteration solving is carried out on the dry ash-free basis sulphur calculation value Sdafj, the dry ash-free basis carbon calculation value Cdafj and the fuel low-level heating amount calculation value Qarj according to the calculation values in the step (S200), and the values are output. Coal quality on-line soft measurement is achieved through the adoption of fire coal moisture on-line measurement information, boiler smoke data and unit running state data.

An intelligent classifying apparatus for fruits is composed of an input fruit sorting-in-lines mechanism, conveying-classifying unit with conveying belt consisting of single fruit holders, supporting chain and motor, weighing unit, photoelectric switches, microprocessor, unloading controller, and discharge ports. It has high speed, precision and efficiency.

The invention discloses a wind tunnel model ice shape measuring method and a wind tunnel model ice shape measuring device. The method is characterized by comprising the following steps of: projecting laser sheet light to the cross section of a model ice layer to form ice shape outline radiography laser stripes, acquiring data of the ice shape outline radiography laser stripes by using an image recording and acquisition device, transmitting the acquired data to an image processing system, acquiring the required ice shape measuring data by data processing, acquiring ice shape outline size by data processing and analysis, and displaying images. The measuring device consists of a camera box, a laser device box, a sheet light height adjusting device and an image acquisition and data processing system. The invention has the advantages of high ice shape measuring precision, convenience in use, high measuring speed, low labor intensity of measuring personnel and the like.

The invention relates to an ultrasonic attenuation spectrum principle based method for measuring the average particle size and concentration of two types of mixed solid particles in a liquid or gas medium. The ultrasonic attenuation spectrum principle based method comprises the following steps of step 1, measuring an experimental measurement ultrasonic attenuation spectrum alpha (f) under the condition that the two types of solid particles A and B are located in a measurement area, wherein f is the ultrasonic frequency; step 2, calculating an acoustic attenuation coefficient Kext of the particle and acoustic wave effect; step 3, determining whether the particles are A particles or B particles and determining whether phonons are absorbed or scattered through the acoustic attenuation coefficient; step 4, calculating a scattering emergence angle theta M1 of the scattered phonons; step 5, continuing to calculate a theoretical ultrasonic attenuation spectrum through a result of the step 4; step 6, establishing an objective function according to the theoretical ultrasonic attenuation spectrum and the experimental measurement ultrasonic attenuation spectrum to solve the particle size and volume concentration. The ultrasonic attenuation spectrum based mixed solid particle size and concentration measurement method can be applied to the two types of mixed solid particles and laboratory scientific research and the online measurement and the application of the industrial field can be implemented.

The invention discloses an in-place measuring method for runout of a high precision gyrorotor. The in-place measuring method comprises the following steps of: stopping rotation of a shaft to be measured, installing a laser displacement sensor, electrical vortex sensors and Hall sensors, and installing a sign that can be identified by the Hall sensors on the shaft to be measured; adjusting positions of the sensors by taking the first electrical vortex sensor sleeved with the Hall sensor as a standard; enabling the surface of the shaft to be measured to be adsorbed with four pieces of magnetic steel which serve as signs can be identified by the Hall sensors; rotating the shaft to be measured, after the rotating speed is stable, collecting periodical pulse signals output by the Hall sensors; adjusting the shaft to be measured to have the proper rotating speed; obtaining signals measured by each electrical vortex sensor; working out an comprehensive runout error, and working out a runout value of a workpiece to be measured on a measuring section. The in-place measuring method for the runout of the high precision gyrorotor has the advantages of being capable of separating rotating error of a machine tool spindle, and providing runout of the high precision gyrorotor with high precision runout information.

The invention discloses a circular saw blade wear amount online measurement method based on machine vision. The measurement method is based on a measurement device which comprises an industrial camera, an image acquisition card and an industrial control computer. The measurement method comprises the steps that the image acquisition card is triggered by the industrial control computer, and a circular saw blade image is obtained through the industrial camera; preprocessing and binary processing are performed on the image; the single pixel edges of the circular saw blade image are extracted; the straight line segments of the circular saw blade edges are extracted; the two line segments on the same saw tooth are determined; and front knife face cutting edge wear amount and rear knife face cutting edge wear amount of the circular saw blade are solved. The circular saw blade wear amount online measurement method is great in real-time performance and high in detection precision and is the effective circular saw blade wear amount online measurement method, and the reliable basis is provided for compensation of a compensation mechanism by the detection result so that plate material cutting efficiency and quality can be enhanced.

The present invention discloses a main bearing reduced scale performance test bench of a large wind turbine. The main bearing reduced scale performance test bench of the large wind turbine comprises a fixed platform, a driving device, a rotor device, a loading device, a hydraulic system, a control device and a test system. The driving device, the rotor device and the loading device are fixedly connected with the fixed platform in turn, and the test system is installed between the outer ring transitional disk and the inner ring transitional disk of the loading device. The main bearing reduced scale performance test bench of a large wind turbine is able to satisfy integrated performance tests with different types and sizes; and the simulation of the actual loaded condition of the main bearing may be performed through combined loading of oil cylinders at different positions, and the synchronous measurement of performance parameters such as the temperature, the vibration, the rotating speed, the friction torque, the static tensile strain of the bearing, and the like are realized. Therefore the test cost of the wind power main bearing is greatly reduced, and the main bearing reduced scale performance test bench of a large wind turbine has an important significance for China wind power bearing technology development.

The invention discloses a biochemical oxygen demand BOD soft measurement method based on elastic radical basis function neural network, belonging to the technical field of detection. The sewage processing process has severe production condition and serious random disturbance, has the characteristics of strong nonlinearity, large time varying and serious lag and is hard to build a precise mathematical model by mechanism analysis. The invention utilizes the liveness function of an RBF neuron to judge the activeness of the neuron, and divides the neuron with strong activeness; then, joint strength between the hidden layer neuron and the output layer neuron of an RBF neuron network is analyzed by calculating a mutual information dependency function so as to revise the neural network structureaccording to the mutual information intensity; and finally, the parameter of the neural network is adjusted until the network structure satisfies the requirement on processing information. The invention improves the quality and the efficiency of sewage processing, lowers sewage processing cost and provides in-time water quality and relevant parameter monitoring for realizing closed loop control for the sewage processing process so as to accelerate sewage treatment plants to efficiently and stably operate.

The invention provides a monitoring device and a monitoring method for a mining FBG roof separation layer. The device comprises a vertical measurement barrel and a packaging casing, wherein fixed pulleys, tape pulleys and constant-strength cantilever beams are symmetrically arranged in the packaging casing; a steel wire rope penetrates through the tape pulleys and the fixed pulleys and penetrates out from a steel wire rope guide hole in the top part of the vertical measurement barrel; one end of the steel wire rope is connected with an anchor head; a shallow part measurement point and a deep part measurement point are distributed inside a drill hole; the anchor head is pushed to the measurement points in the drill hole; when the stress of the steel wire rope changes, the stress change is displayed through wavelength values of an FBG A and an FBG B; a wavelength demodulation device is used for demodulating the wavelength values into digital signals, the digital signals are sent to a computer for real-time processing, and a separation layer numerical value is combined for drawing a separation layer quantity changing curve and a set separation layer boundary value; whether the separation layer exists is judged; and the data change of the roof separation layer is monitored in real time. Temperature compensation is performed with a differential form, on-line measurement of the roof separation layer is realized, the reliability and the accuracy are high, an early warning signal can be issued, and roof fall accidents can be avoided.

A multifunctional in-situ electrochemical measuring device used for the tension test belongs to the electrochemical field. The multifunctional in-situ electrochemical measuring device used for the tension test is characterized in that a reference electrode, an auxiliary electrode and a working electrode are arranged in a top cover of the multifunctional in-situ electrochemical measuring device according to design and measurement requirements; the conductive wires of all the electrodes are connected with an electrochemical workstation; the air input of an air inlet and the air output of an air outlet are adjusted; an installed heating resistor and a thermocouple are connected with a temperature controlling device; the water flow of a water inlet and the water flow of a water outlet are adjusted, and the water inlet and the water outlet are connected with an externally connected water pump. The rotation time of a stepping motor is set, electrochemical parameters of a tensile test sample are measured after the temperature and the pressure are increased to the parameters required by the tension test, and the tension test is conducted after the force of the tensile test sample is adjusted. The multifunctional in-situ electrochemical measuring device used for the tension test has simple and easy method, can measure the electrochemical parameters of the tensile test sample in a long time and can simulate the temperature, the moisture, the gas, the alternation of wetting and drying, the surface scouring, the multiphase medium and complex environment of the tensile test sample.

The invention discloses a method and device for rapidly measuring sidewall appearance of a micro-nano deep groove structure, which can simultaneously and rapidly measure the parameters of the sidewall appearance of the micro-nano deep groove structure, such as line width, groove depth, sidewall angle, sidewall roughness and the like. The method comprises the steps of: projecting elliptical polarized lights, which is obtained by polarizing light beams with the wavelengths ranging from near infrared waveband to middle infrared waveband, onto the surface of a structure to be measured; collecting zero-level diffraction signals on the surface of the structure to be measured, and calculating to obtain a measured infrared spectroscopic ellipsometry of the micro-nano deep groove structure; calculating theoretical spectroscopic ellipsometries in the near infrared waveband and the middle infrared waveband respectively by using a wavelength allocation modeling method, matching the theoretical spectroscopic ellipsometries with the infrared spectroscopic ellipsometry measured in the experiment by using a stepwise spectral inversion method, and sequentially extracting the groove structure parameter and the roughness parameter. The device comprises an infrared light source, first, second, third and fourth off-axis parabolic mirrors, a Michelson's interferometer, a planar reflector, a polarizer, a sample bench, an analyzer, a detector and a computer; and the method is a noncontact, nondestructive low-cost method for rapidly measuring the sidewall appearance.

The invention discloses a method for detecting the concentration of gas-phase alkali metal in boiler flame on line by directly adopting flame emission spectral analysis. The method comprises the steps of firstly, selecting a characteristic spectral line of to-be-measured alkali metal, then constructing a fitting model of the radiation intensity of the characteristic spectral line relative to flame temperature and the concentration of the gas-phase alkali metal, then determining a fitting coefficient through experimental calibration, finally, measuring a radiation spectrum of a flame object by a portable fiber-optic spectrometer, so as to obtain the flame temperature and the radiation intensity of the characteristic spectral line of the alkali metal, substituting into the established fitting model of which the fitting coefficient is known, and calculating to obtain the concentration of the gas-phase alkali metal in the flame. The method has the advantages of simple equipment, low cost and convenience in industrial field measurement, the concentration of the gas-phase alkali metal in the boiler-inside combustion flame can be conveniently and precisely detected on line, and the contents of various kinds of alkali metal can be simultaneously detected.

The invention discloses a method and device for testing accelerated degradation of the friction moment of a ball screw pair and belongs to the technical field of detection of ball screw pairs. The ball screw pair is connected with a sliding plate through a replaceable main nut and a replaceable auxiliary nut on the two sides respectively. In the test condition, the ball screw pair drives the sliding plate to reciprocate through the main nut, rotation of the sliding plate is limited by the auxiliary nut through a limiting rod, and load testing is conducted on the sliding plate through a load cylinder. In the testing condition, the ball screw pair drives the sliding plate to reciprocate through the auxiliary nut, the main nut is connected with a pull pressure sensor installed on the sliding plate through a force measurement rod, so that the friction torque between the main nut and a lead screw is obtained accurately. During an accelerated degradation test, axial stepping accelerated loading is conducted on the ball screw pair through the axial load cylinder. Modeling of the friction torque degradation process of the ball screw pair can be achieved through the ball screw pair friction torque data obtained through a short-time acceleration test, and the performance degradation life of the ball screw pair is predicted in a short period of time and with low cost.

The invention relates to a large-caliber high-gradient optical mirror surface on-line measuring system which comprises an optical fiber light source, a converging light path light split system, a replaceable measuring grating, a high-precision plane reflecting mirror, a large-caliber high-gradient optical mirror surface, a digital CCD (Charge Coupled Device) and a computer information processing system. In the invention, after light emitted out from a numerical aperture optical fiber light source passes through the measuring grating, a group of shadow fringes is generated, and after passing through the converging light path light split system and the high-precision plane reflecting mirror, the shadow fringes are projected onto the large-caliber high-gradient optical mirror surface and then reflected back by the large-caliber high-gradient optical mirror surface according to the original path; when the shadow fringes pass through the high-precision plane reflecting mirror and the converging light path light split system, another light path is generated, and a conjugate image of the light source is generated in the light path; after the conjugate image is acquired by the digital CCD, the conjugate image is transmitted to a computer and analyzed and processed by the computer information processing system; and the surface shape error of the large-caliber high-gradient optical mirror surface is worked out through comparing the deviations between the returned image and an ideal image.

The invention discloses a single-beam-laser multidimensional speed measuring system of a high-speed rarefied gas flow field. The single-beam-laser multidimensional speed measuring system comprises a high-speed rarefied gas wind tunnel (1), a laser light source module (2), a laser beam shaping module (3), a high-voltage arc discharge module (4), a fluorescent signal collecting and recording module (5), a data processing module (6) and a time sequence synchronous control module (7). The invention further provides an application method of the system.

The invention relates to a method for measuring particle diameter and concentration based on an ultrasonic pulsation principle. A transmitted acoustic intensity is attenuate when an incidence ultrasonic wave is scattered and absorbed through a granular medium; focused ultrasound is adopted and a measurement area is arranged in an ultrasonic focused acoustic beam band; when a ratio of the particle diameter to ultrasonic focused acoustic beam diameter is controlled within a scope of 0.1-20, quantity and diameters of particles passing the acoustic beam vary with time, and transmitted acoustic intensity fluctuates and varies with time, to generate an acoustic pulse effect; random pulsation of the ultrasonic signal is related to quantity and diameters of particles in the ultrasonic focused acoustic beam measurement area at the moment of measuring; a random variation sequence of the transmitted ultrasonic intensity is measured and is calculated and analyzed, therefore, average particle diameter and concentration of particles are calculated through the ultrasonic pulsation principle. The method disclosed by the invention can realize online measurement; the method is applicable to laboratory scientific research, and is specifically applicable to the industrial field.