Patents
Literature
Hiro is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Hiro

34results about How to "With non-contact measurement" patented technology

Small-passage gas-liquid phase flow pattern identification device and method based on photovoltaic array sensor

The invention discloses a small-passage gas-liquid phase flow pattern identification device and method based on a photovoltaic array sensor. The small-passage gas-liquid phase flow pattern identification device comprises a transparent pipe with a small diameter, a laser source, a beam splitter prism, an optical power meter, a beam expander, a slit, the photovoltaic array sensor, an amplifying and filtering circuit, a data acquisition module and a microcomputer. The measurement signal for reflecting the gas-liquid phase flow pattern change is obtained by the photovoltaic array sensor, the characteristic value matrix of the measurement signal is extracted as original data, the original data are compressed by a principal component analysis method, the compressed data matrix is input into a flow type classifier of a support vector machine, thus the two-phase flow pattern is identified. An effective path is provided to analyze the small-passage gas-liquid phase flow character and detect the parameters. The corresponding device has the advantages of simple structure, low cost, non contact measurement, high identification correct rate and wide application range, and provides useful reference for identifying the small-passage two-phase flow pattern.
Owner:ZHEJIANG UNIV

Non-conducting medium film thickness online detecting device of coplane capacitive sensor

The invention discloses a non-conducting medium film thickness online detecting device of a coplane capacitive sensor. The non-conducting medium film thickness online detecting device comprises a detecting circuit, a data collecting card, an interface converter and a computer. The detecting circuit comprises a measuring exciting circuit, a reference capacitor, a main amplifier, a sensor measuring capacitor, a signal demodulator circuit, a signal separating circuit and a correcting amplifying circuit. The non-conducting medium film thickness online detecting device has the advantages of being good in adaptability, free of radial pollution, good in dynamic response, capable of achieving non-contact measuring, small in self temperature coefficient and the like and has wide application in online measuring of the non-conducting medium film thickness.
Owner:SHANDONG JIANZHU UNIV +2

Infrared thermal imaging air tightness tester

The invention discloses an infrared thermal imaging air tightness tester, comprising a test module, a control module, a thermal imaging module, a moving module, a data processing module and a tester frame; the tester frame comprises a bottom plate, a support frame and an upper seal plate; a foot pad is arranged on the side, close to the ground, of the bottom plate, one end of the foot pad is fixed on the bottom plate, and a rubber pad is arranged at the other end of the foot pad. The invention provides an infrared thermal imaging air tightness tester, which has high safety coefficient and can be monitored in real time.
Owner:THE INSPECTION & QUARANTINE TECH CENT ZHEJIANG ENTRY EXIT INSPECTION & QUARANTINE BUREAU +1

Detection sensor and detection method for angle of rocker arm of coal cutter

The invention discloses a detection sensor and a detection method for an angle of a rocker arm of a coal cutter. The sensor includes a base, a base top cover and a rocking bar; the base is connected with a revolving shaft, and the rocking bar is fixedly connected with the revolving shaft; one end of the rocking bar that is not fixedly connected with the revolving shaft is connected with a connection base; the top of the revolving shaft is provided with circular magnetic steel; the top of the base top cover is connected with a sensor protective shell; an inner cavity of the sensor protective shell is a circuit board installation cavity and a sensor circuit board is installed in the circuit board installation cavity; the sensor circuit board is integrated with a sensor circuit; and the sensor circuit includes a microprocessor module, a power supply module, a communication module, an angle sensor, and a display module. The method includes the following steps: 1. installing the sensor; and2. detecting the angle of the rocker arm of the coal cutter. The sensor is novel and reasonable in design, is convenient to implement, is good in work stability and reliability, is strong in anti-interference capability, is high in detection precision, provides guarantee for realization of automatic height adjustment of the coal cutter, is strong in practicability, and is convenient for popularization and usage.
Owner:XIAN UNIV OF SCI & TECH

Reference signal constraint-based mechanical characteristic acoustic signal frequency-domain semi-blind extraction method

The invention relates to a reference signal constraint-based mechanical characteristic acoustic signal frequency-domain semi-blind extraction method, and belongs to the technical field of operation maintenance of mechanical equipment. The method comprises the following steps: constructing a multi-scale morphology filter for a failure signal characteristic on the basis of a dynamic particle swarm algorithm with higher global optimization capability, and maximally weakening background noise interference; constructing a reference signal in combination with structural parameters of a mechanical part, and further performing complex component blind separation band by band by virtue of a unit reference signal constraint semi-blind extraction method; solving order uncertainty problems to obtain a separated and restored source signal to finally realize the extraction and separation of the mechanical failure characteristic signal by virtue of the improved KL distance between complex components. Different from vibration monitoring requiring the mounting of a sensor on the surface of mechanical equipment, acoustic monitoring only requires the placement of 1 to 2 microphones around the equipment, and then the failure characteristic signal can be extracted from a picked up mechanical acoustic signal for further failure source positioning.
Owner:KUNMING UNIV OF SCI & TECH

Electromagnetic shake table using absolute position feedback to realize active positive rigidity resilient support

An electromagnetic shake table using absolute position feedback to realize active positive rigidity resilient support belongs to the vibration metering technical field; the active positive rigidity resilient support method employs an absolute type linear raster ruler as a feedback displacement sensor, and outputs a Lorentz force in a constant proportion with the relative displacement of the absolute zero point position, thus enabling an electromagnetic shake table moving-coil to have the linearity rigidity resilient support in large stroke motions; the electromagnetic shake table moving-coil is connected in series with multistage power resistors so as to increase the load impedance, thus allowing a power amplifier to have a high signal to noise ratio while outputting a milliampere level ultralow frequency current; the electromagnetic shake table can combine the large stroke with the linear resilient support and the high signal to noise ratio, thus providing a large stroke high performance electromagnetic shake table control technology scheme for the ultralow frequency vibration calibration.
Owner:HARBIN INST OF TECH

Dynamic detection device for plate blank width based on FPGA (Field Programmable Gate Array) and laser triangulation measurement

The invention discloses a dynamic detection device for the plate blank width based on an FPGA (Field Programmable Gate Array) and laser triangulation measurement. The dynamic detection device comprises a roller bed, two laser triangulation rangefinders and a plate blank width measurement centralized controller taking the FPGA as a core, and is characterized in that the two laser triangulation rangefinders are installed at two sides of the roller bed respectively, a clock frequency division module is in one-way connection with a distance data analysis module, a plate blank width calculation module, a liquid crystal display driving module, a D / A conversion driving module and an RS-485 communication module, the distance data analysis module is in one-way connection with the plate blank width calculation module, and the plate blank width calculation module is in one-way connection with the liquid crystal display driving module, the D / A conversion driving module and the RS-485 communication module. The dynamic detection device has the characteristics of non-contact measurement, high accuracy, high response speed, high anti-interference ability, convenient field installation and the like.
Owner:CHANGZHOU INST OF TECH

Non-contact online measurement method and apparatus of boiler main steam pipeline macroscopic displacement

A non-contact online measurement method of boiler main steam pipeline macroscopic displacement comprises the following steps: 1, establishing a spatial coordinate system of a pipeline center line and elastic support hangers; 2, simplifying the elastic support hangers into an upper rigid rod, a lower rigid and a middle spring, and respectively setting two marking points on the lower rigid rod; 3, arranging a high-definition camera, and connecting a main control computer through a wireless bridge; 4, acquiring the spatial coordinates of the marking points in the coordinate system through adopting a three dimensional reconstruction algorithm; 5, acquiring the coordinates of the marking points after creep deformation; 6, establishing the linear equation of the lower segment of the elastic support hangers; and 7, combining the linear equation with the curve equation of the external surface of the boiler main steam pipeline to obtain the coordinate of an intersection point B' of the linear l1 equation and the external surface of the boiler main steam pipeline, and accurately calculating the macroscopic displacement of the pipeline in every direction after taking regard of errors. High-stability and high-precision pipeline macroscopic displacement is obtained in an online non-contact manner.
Owner:ELECTRIC POWER RES INST OF GUANGDONG POWER GRID +1

Swinging reversing two-stage pressurization zero-clearance type ionic liquid compressor

The invention belongs to the technical field of compressors, and particularly relates to a swinging reversing two-stage pressurization zero-clearance type ionic liquid compressor. Ionic liquid compressors use ionic liquid instead of metal pistons to generate high pressure under isothermal condition, however, an existing ionic liquid compressor uses 5-stage compression, and is complex in structure,difficult to machine and high in cost, so that the construction and development of a hydrogen refueling station are limited. The swinging reversing two-stage pressurization zero-clearance type ionicliquid compressor comprises a hydraulic mechanism and a gas pressurization mechanism which are mutually connected; the gas pressurization mechanism comprises a hydraulic swinging assembly, the hydraulic swinging assembly is connected with a first-stage gas pressurization assembly, and the hydraulic swinging assembly is connected with a second-stage gas pressurization assembly; and the hydraulic swinging assembly is connected with the hydraulic mechanism through a reversing assembly. According to the compressor, the structure is simple, machining is convenient, the control precision is high, the energy consumption is low, the clearance volume is zero, the universality is strong, hydrogen is not polluted and the cost is low.
Owner:XI AN JIAOTONG UNIV

Photo-thermal spectrum trace gas detection device and method based on cavity enhancement

The invention discloses a photo-thermal spectrum trace gas detection device and method based on cavity enhancement. Llow-frequency sawtooth waves generated by a signal generator and high-frequency sine waves generated by a lock-in amplifier are sent into a summator, and superposed signals form modulation signals of laser wavelength; a modulation signal is sent into a laser controller, the wavelength of laser output by the tunable semiconductor laser is changed through a temperature module and a current module, the laser enters a gas chamber of gas to be measured after passing through a laser collimation system, and target gas to be measured absorbs part of laser energy; laser is emitted from the gas chamber of the gas to be measured and then is focused to the root position of a quartz tuning fork interdigital through a light spot of a focusing lens, a generated vibration signal is converted into an electric signal due to photoinduced thermoelastic deformation and a piezoelectric effect, and the electric signal is input into a lock-in amplifier for harmonic signal acquisition; the harmonic data are finally input into a computer to be processed, and the gas concentration is inverted. The device has the advantages of high sensitivity, low cost, non-contact measurement and the like.
Owner:HARBIN INST OF TECH

Phase difference real-time adjusting type three-level pressurizing zero-clearance type ionic liquid compressor

The invention belongs to the technical field of compressors, and particularly relates to a phase difference real-time adjusting type three-level pressurizing zero-clearance type ionic liquid compressor. Ionic liquid is adopted in the ionic liquid compressor for generating high pressure, but, an existing ionic compressor adopts five-level compression, the structure is complex, machining is difficult, cost is high, the provided phase difference real-time adjusting type three-level pressurizing zero-clearance type ionic liquid compressor comprises a hydraulic mechanism and a gas pressurizing mechanism which are connected, the gas pressurizing mechanism comprises a first-level gas pressurizing assembly, a second-level gas pressurizing assembly and a third-level gas pressurizing assembly, the first-level gas pressurizing assembly is connected with the hydraulic mechanism through a first reversing assembly, the second-level gas pressurizing assembly is connected with the hydraulic mechanismthrough a second reversing assembly, and the third-level gas pressurizing assembly is connected with the hydraulic mechanism through a third reversing assembly. The compressor is simple in structure,convenient to machine, high in control precision, low in energy consumption, zero in clearance volume, high in generality, free of pollution to hydrogen and low in cost.
Owner:XI AN JIAOTONG UNIV

High-efficiency supercharged zero-clearance ionic liquid compressor with precise and adjustable piston stroke

ActiveCN111365210BPrecise adjustable boostPrecisely adjustable piston strokePositive displacement pump componentsPump controlHydraulic cylinderHigh pressure hydrogen
The application belongs to the technical field of compressors, in particular to a high-efficiency supercharged zero-clearance ionic liquid compressor with precise and adjustable piston strokes. The existing ion compressor adopts 5-stage compression, the structure is complicated, the processing is difficult and the cost is expensive. The application provides a high-efficiency supercharged zero-clearance ionic liquid compressor with precise and adjustable piston stroke, including an oil supply component, a reversing component, a gas compression component, a first gas transmission component, a gas-liquid separation component and a second gas transmission component Assembly; the gas compression assembly includes a hydraulic cylinder and a gas compression cylinder, the hydraulic cylinder is provided with a first T-shaped piston, the first T-shaped piston is connected to a displacement sensor, and the end of the first T-shaped piston is connected to the first T-shaped piston The two T-shaped pistons are connected, and the second T-shaped piston is arranged in the gas compression cylinder. The compressor can complete the compression process from low-pressure hydrogen to high-pressure hydrogen when the second T-shaped piston completes a downward (inhalation) and upward (compressor exhaust) action, and the compression is efficient.
Owner:XI AN JIAOTONG UNIV

High-precision six-degree-of-freedom measurement method and device based on laser range finder

PendingCN113028987ASolve the problem of complex structure and low measurement accuracyCompact structureUsing optical meansData processing systemLaser ranging
The invention provides a high-precision six-degree-of-freedom measurement method and device based on a laser range finder, and solves the problem of simultaneous measurement of six degrees of freedom of movement of an object along an X direction, a Y direction and a Z direction and rotation around an X axis, a Y axis and a Z axis in a space rectangular coordinate system. The device comprises a high-precision laser interference range finder, an external reflection pyramid mirror, a static coordinate flat plate, a movable coordinate flat plate and a data processing system. The laser interference range finder and the external reflection pyramid mirror are used to measure six distances from six points on the movable coordinate flat plate to six corresponding points on the static coordinate flat plate, and then a position coordinate resolving method provided by the invention is used to resolve the variation of the movable coordinate flat plate moving along the X direction, the Y direction and the Z direction and rotating around the X axis, the Y axis and the Z axis for six degrees of freedom. The method has the characteristics of high precision and simple structure.
Owner:INST OF OPTICS & ELECTRONICS - CHINESE ACAD OF SCI

All-fiber laser detection system for tunnel safety monitoring and working method

The invention relates to an all-fiber laser detection system for tunnel safety monitoring and a working method, and belongs to the technical field of tunnel safety monitoring. The system comprises a laser, an optical fiber beam splitter 1 is arranged on an output light path, two paths of output of the optical fiber beam splitter 1 are respectively connected to an optical fiber beam splitter 2 andan optical fiber modulator, and the output of the optical fiber modulator is connected to an optical fiber beam splitter 3; two outputs of the optical fiber beam splitter 3 are respectively connectedto an optical fiber beam combiner 1 and an optical fiber beam combiner 2; one path of output of the optical fiber beam splitter 2 is connected to the optical fiber beam combiner 1 through an optical fiber circulator, and the other path of output of the optical fiber beam splitter 2 is connected to the optical fiber beam combiner 2 through an optical fiber coupling head; the optical fiber beam combiner 1 is connected to a data acquisition processing and control system through a photoelectric detector 1, and the optical fiber beam combiner 2 is connected to the data acquisition processing and control system through a photoelectric detector 2. The gas measurement and displacement deformation measurement can be realized at the same time; the gas measurement sensitivity is high, and the displacement deformation measurement accuracy is high.
Owner:SHANDONG UNIV

Non-contact displacement measurement system

The invention discloses a non-contact displacement measurement system, which comprises a light source module, a demodulation module and a sensing module. The sensing module is connected with a photoelectric detector through a receiving optical fiber, and the output end of the photoelectric detector is connected with a demodulation system through an A / D converter and a divider. The sensing module comprises a metal shell, one end of the metal shell is provided with a mounting groove, the sapphire glass is arranged in the mounting groove, and a cooling cavity is formed between the sapphire glass and the mounting groove; an optical fiber bundle is installed in the cooling cavity, and one end of the transmitting optical fiber, one end of the first receiving optical fiber and one end of the second receiving optical fiber are converged to the optical fiber bundle arranged in the cooling cavity through optical fiber conversion connectors respectively; the interior of the cooling cavity is cooled through inert gas. External high-temperature and high-pressure gas can be isolated through the sapphire glass, heat is taken away through cold air circulation in the cooling cavity, normal work of the system is guaranteed, and good practicability is achieved.
Owner:CHENGDU KAITIAN ELECTRONICS

A frequency-domain semi-blind extraction method of mechanical characteristic acoustic signals based on reference signal constraints

The invention relates to a reference signal constraint-based mechanical characteristic acoustic signal frequency-domain semi-blind extraction method, and belongs to the technical field of operation maintenance of mechanical equipment. The method comprises the following steps: constructing a multi-scale morphology filter for a failure signal characteristic on the basis of a dynamic particle swarm algorithm with higher global optimization capability, and maximally weakening background noise interference; constructing a reference signal in combination with structural parameters of a mechanical part, and further performing complex component blind separation band by band by virtue of a unit reference signal constraint semi-blind extraction method; solving order uncertainty problems to obtain a separated and restored source signal to finally realize the extraction and separation of the mechanical failure characteristic signal by virtue of the improved KL distance between complex components. Different from vibration monitoring requiring the mounting of a sensor on the surface of mechanical equipment, acoustic monitoring only requires the placement of 1 to 2 microphones around the equipment, and then the failure characteristic signal can be extracted from a picked up mechanical acoustic signal for further failure source positioning.
Owner:KUNMING UNIV OF SCI & TECH

Non-contact online measurement method and device for macroscopic displacement of boiler main steam pipe

A non-contact online measurement method of boiler main steam pipeline macroscopic displacement comprises the following steps: 1, establishing a spatial coordinate system of a pipeline center line and elastic support hangers; 2, simplifying the elastic support hangers into an upper rigid rod, a lower rigid and a middle spring, and respectively setting two marking points on the lower rigid rod; 3, arranging a high-definition camera, and connecting a main control computer through a wireless bridge; 4, acquiring the spatial coordinates of the marking points in the coordinate system through adopting a three dimensional reconstruction algorithm; 5, acquiring the coordinates of the marking points after creep deformation; 6, establishing the linear equation of the lower segment of the elastic support hangers; and 7, combining the linear equation with the curve equation of the external surface of the boiler main steam pipeline to obtain the coordinate of an intersection point B' of the linear l1 equation and the external surface of the boiler main steam pipeline, and accurately calculating the macroscopic displacement of the pipeline in every direction after taking regard of errors. High-stability and high-precision pipeline macroscopic displacement is obtained in an online non-contact manner.
Owner:ELECTRIC POWER RES INST OF GUANGDONG POWER GRID +1

ZPW-2000A track circuit transmitter and receiver fault diagnosis method

The invention discloses a ZPW-2000A track circuit transmitter and receiver fault diagnosis method. The method comprises the following steps: S1, acquiring sound data of track circuit transmitter equipment and track circuit receiver equipment in various states; S2, performing feature extraction on the sound data in each state through Mel-frequency cepstral coefficient or wavelet packet analysis to obtain a corresponding feature matrix in each state; S3, constructing a corresponding data set based on the feature matrix in each state; and S4, carrying out random forest training and classification on the data set corresponding to each state to obtain a data classification result, and obtaining an analysis result of each fault type based on the data classification result. According to the invention, a data acquisition mode is set as a recording mode, and the method has the advantages of non-contact measurement and high safety. In addition, a ZPW-2000A track circuit transmitter and receiver fault diagnosis method based on a machine learning algorithm is adopted, the defects that according to a traditional detection method, maintainers need to have rich experience, and the maintenance process is complex are overcome, and the maintenance efficiency is improved.
Owner:SHANGHAI INST OF TECH

Four-beam Doppler velocity measurement method for carrier vehicle

The invention provides a four-beam Doppler velocity measurement method for a carrier vehicle. The speed of a vehicle body is measured by using a four-beam Doppler velocity measurement technology. TheDoppler velocity measurement technology has the advantages of high precision, fast dynamic response, a wide measurement range, non-contact measurement and the like, is suitable for various measured objects, and can also be used for carrying out non-contact measurement on long-distance objects. A four-beam configuration scheme is adopted, accurate three-dimensional speed information can be providedfor the vehicle body, redundant structure design is added, the reliability of the system is improved, multiple demodulation calculation methods are achieved based on a three-beam model, speed correction is conducted on a single three-beam system, and the speed measurement precision of the system is improved.
Owner:湖南率为控制科技有限公司

Optical detection system and method for phase distribution of gas-liquid two-phase flow in small pipeline

The invention discloses a small pipeline gas-liquid two-phase flow phase distribution optical detection system and method. The method comprises the following steps: firstly, irradiating a measured gas-liquid two-phase flow from two mutually vertical directions by adopting two sheet-shaped light beams, and synchronously measuring light intensity distribution generated by the measured gas-liquid two-phase flow; then, in combination with light intensity distribution data when the pipeline is filled with the liquid phase, extracting required light intensity distribution characteristic quantity from a measurement result; secondly, establishing a measurement model about small pipeline section phase distribution parameters and light intensity distribution characteristic quantity based on a geometrical optics principle, and realizing gas-liquid phase distribution measurement of the pipe section by utilizing experimental data; and finally, further realizing gas-liquid phase distribution reconstruction and liquid film thickness estimation of the gas-liquid two-phase flow based on multiple groups of phase distribution measurement results. The system has the advantages of non-contact / non-invasive measurement, high time / space resolution, simple device structure and the like; and the method is based on the geometrical optics principle, and an effective and convenient new way is provided forobtaining the section gas-liquid phase distribution information of the gas-liquid two-phase flow of the small pipeline.
Owner:ZHEJIANG UNIV

Method and device for simultaneously measuring sound velocity and refractive index of fluid

The invention discloses a method and device for simultaneously measuring the sound velocity and the refractive index of fluid. Plane mirrors are respectively arranged in the normal direction and the symmetrical direction of probe light so as to adjust the receiving angle of scattered light; two scattered light beams with different scattering angles pass through a focusing lens and two diaphragms and then respectively enter a Fabry-Perot interferometer with a function generator for filtering, and are then received by the photoelectric detector with a shading cylinder and are converted into TTL pulse signals for Rayleigh-Brillouin spectrum analysis. Rayleigh-Brillouin scattering spectrums at different angles are used for decoupling the refractive index and the scattering angle, the influence of the scattering angle and noise interference on sound velocity and refractive index measurement is fundamentally eliminated through a scanning type measurement method, and the method has the characteristics of non-contact measurement, irrelevance with body size precision, easiness in high-temperature measurement and the like, and method and device have important application prospects in the fields of energy chemical industry, national defense military industry, industrial production, scientific research and the like.
Owner:XI AN JIAOTONG UNIV

Phase difference real-time adjustable three-stage supercharged zero-clearance ionic liquid compressor

The application belongs to the technical field of compressors, in particular to a three-stage supercharged zero-gap ionic liquid compressor with real-time adjustable phase difference. The ionic liquid compressor uses ionic liquid to generate high pressure, but the existing ionic compressor uses 5-stage compression, the structure is relatively complicated, the processing is difficult and the cost is expensive. The application provides a three-stage supercharged zero-gap ionic liquid compressor with real-time adjustable phase difference, which includes a hydraulic mechanism and a gas booster mechanism connected to each other; the gas booster mechanism includes a first-stage gas booster assembly, a second stage The first-stage gas booster assembly and the third-stage gas booster assembly, the first-stage gas booster assembly is connected to the hydraulic mechanism through the first reversing assembly, the second-stage gas booster assembly is connected to the hydraulic mechanism through the second reversing assembly, The third-stage gas pressurization assembly is connected through the hydraulic mechanism of the third reversing assembly. Simple structure, convenient processing, high control precision, low energy consumption, zero clearance volume, strong versatility, no hydrogen pollution, and low cost.
Owner:XI AN JIAOTONG UNIV

Torque calibration measuring device based on flexible bearing

The invention relates to a flexible support based torque calibration and measurement device. Left and right scale pans used for hanging of weights are symmetrically mounted on two sides of a standard torque beam through elastic pieces. A rotation center 'O' of a flexible support coincides with a central axis 'Y' of the standard torque beam. A laser displacement sensor mounted on a base is arranged below the lower end face of the standard torque beam. Left and right electromagnetic torquers are symmetrically mounted on two sides of the lower end face of the standard torque beam. On the condition of a torque load, the laser displacement sensor transmits measured electric signals of displacement variation, of a laser sensor probe and a standard torque lower end face, caused by the torque load to the left electromagnetic torquer or the right electromagnetic torquer after the electric signals are processed by a measuring circuit so as to control the left electromagnetic torquer or the right electromagnetic torquer to generate electromagnetic force to level the standard torque beam. The flexible support based torque calibration and measurement device has the advantage that measurement precision is improved to the utmost by comprehensive measures such as an electromagnetic force equilibrium system, the high-precision laser displacement sensor and a rapid signal tracking and measuring system.
Owner:SHANGHAI MARINE EQUIP RES INST

Device and method for measuring junction temperature of LED (light emitting diode)

The invention provides a device and a method for measuring the junction temperature of an LED (light emitting diode). The method mainly comprises the following steps of: controlling the temperature of the LED by a thermostat; obtaining a relative spectrum of the LED by a spectrum analysis system; obtaining a relative spectrum which corresponds to the junction temperature of the LED under the driving of small current at different temperatures; selecting a wave peak or wave trough strength in the relative spectrum as reference; fitting the relationship of the relative spectrum and the reference since the temperature of the thermostat is approximate to the junction temperature at the time under a short time in the process of small current driving, so that an equation can be obtained; and reversely obtaining the junction temperature of the LED due to the equation and the relative spectrum strength under the practical working condition. The method has the characteristics such as the accuracy of a forward voltage method and the contactless measurement of a peak wavelength method, and provides a set of scientific schemes for the high-efficiency and quick measurement and performance expression of the junction temperature of the LED, the optimization study, etc.
Owner:SHAANXI UNIV OF SCI & TECH

A method for measuring the dispersion of pollutants by means of a plif measurement system in wind-induced flow tests

The invention discloses a method for measuring the diffusion of pollutants through a PLIF measurement system in a wind-induced flow test, performing standard solution proportioning according to the maximum value of solution concentration, performing solution proportioning according to n concentration gradients, and placing the container in the model Add the water in the model to the container at a certain position of the laser point, the water level in the container is consistent with the water level of the model, and the concentration value is 0 at this time, and the brightness of the spot at this time is recorded by the camera; the standard concentration solution Put it in a container, place it at any laser point position in the model, and record the spot brightness at this time through the camera; draw the relationship curve between σ and μ, and fit it to obtain a calibration curve. According to the calibration curve, any measurement point can be induced to emit laser light. The gray value of the fluorescence is restored to the concentration value, and the isoline of the concentration distribution is generated by interpolation. The invention has the characteristics of convenient use, convenient operation, strong practicability and the like.
Owner:NANJING HYDRAULIC RES INST

Small pipeline gas-liquid two-phase flow phase distribution optical detection system and method

The invention discloses a small pipeline gas-liquid two-phase flow phase distribution optical detection system and method. The method comprises the following steps: firstly, irradiating a measured gas-liquid two-phase flow from two mutually vertical directions by adopting two sheet-shaped light beams, and synchronously measuring light intensity distribution generated by the measured gas-liquid two-phase flow; then, in combination with light intensity distribution data when the pipeline is filled with the liquid phase, extracting required light intensity distribution characteristic quantity from a measurement result; secondly, establishing a measurement model about small pipeline section phase distribution parameters and light intensity distribution characteristic quantity based on a geometrical optics principle, and realizing gas-liquid phase distribution measurement of the pipe section by utilizing experimental data; and finally, further realizing gas-liquid phase distribution reconstruction and liquid film thickness estimation of the gas-liquid two-phase flow based on multiple groups of phase distribution measurement results. The system has the advantages of non-contact / non-invasive measurement, high time / space resolution, simple device structure and the like; and the method is based on the geometrical optics principle, and an effective and convenient new way is provided forobtaining the section gas-liquid phase distribution information of the gas-liquid two-phase flow of the small pipeline.
Owner:ZHEJIANG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Eureka Blog
Learn More
PatSnap group products