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2020 Vol. 41, No. 6
Published: 2020-06-28
 
633 Preliminary Research on Practical Acoustic GasThermometry Using Helium
YANG Sheng-liang,FENG Xiao-juan,LIN Hong,ZHANG Jin-tao,REN Cheng
DOI: 10.3969/j.issn.1000-1158.2020.06.01
As a new generation nuclear reactor, reliable temperature measurement in a high temperature gas cooled reactor (HTGR) presents unique challenges. The conventional temperature measurement are based on the properties of thermometers materials calibrated by the laboratory, and thermometers could drift or even lose efficiency due to the variation of the properties and the lack of timely calibration, especially when the thermometers are exposed to high temperature and radioactive environment for a long time. Acoustic gas thermometry determines the thermodynamic temperature of a monatomic gas from measurements of the speed of sound in the gas. Because the helium in the gas-cooled reactor is stable, the temperature measurement using the speed of sound in helium could achieve higher reliability. A preliminary research on the practical acoustic gas thermometry using helium was implemented. A measurement system of the practical acoustic thermometry using cylindrical resonator was designed. The resonant frequency in helium was measured from 488K to 806K using acoustic waveguides. Then perturbations from the thermal and viscous boundary layers were corrected, and the thermodynamic temperature was determined based on the acoustic virial equation of state of helium. The relative standard deviations of the resonant frequency measurements are smaller than 0.07%, the signal to noise ratio of the measurements is acceptable. The relative difference between the thermodynamic temperature and the temperature measured by a thermocouple is less than 1%. The preliminary research supports the continuous investigation on the acoustic gas thermometry applying in harsh environments.
2020 Vol. 41 (6): 633-639 [Abstract] ( 370 ) HTML (1 KB)  PDF (1003 KB)  ( 335 )
640 Research on Model Temperature Prediction Method Based on Fireworks Algorithm and Long and Short Time Memory Network
ZHANG Dian-fan,LI Zi-hao,CHENG Shu-hong
DOI: 10.3969/j.issn.1000-1158.2020.06.02
Aiming at the problems of low precision of mold temperature and difficulty in selecting network parameters, based on fireworks algorithm to optimize the long and short time memory network, a mold temperature prediction model is proposed, which provides a basis for automatic control of casting mold temperature. Firstly, according to the production casting process, the main variables affecting the casting system are selected. The grey relational analysis is used to obtain the grey correlation degree of each variable and remove the small correlation degree, and the data set of the mold temperature influence factor variable is established. Secondly, the fireworks algorithm is used to optimize the long and short time memory network to establish a mold temperature prediction model. Finally, the prediction results are compared with BP neural network and long-term short-term networks. Experiments show that the absolute error of the model temperature prediction method based on the long-term and short-term memory network optimized by the firework algorithm is less than 2.4℃ and the mean absolute percentage error is less than 0.12.
2020 Vol. 41 (6): 640-645 [Abstract] ( 279 ) HTML (1 KB)  PDF (994 KB)  ( 229 )
646 Spectral Responsivity Calibration of Infrared Radiometer Based on Piecewise Linear Calibration Method
HE Ying-feng,DENG Le-wu,WU Jie,WEI Ping,WANG Rui
DOI: 10.3969/j.issn.1000-1158.2020.06.03
The responsibility characteristics of the SR 5000N measurement system is calibrated based on blackbody radiation source which meets the national high temperature standard. A calculation model of the spectral responsivity calibration is established and the calibration is carried out by using the SR 5000N measurement system at 373~773K. The experiment results show that the measured infrared spectra in the wavelength range of 8 ~14μm at 373~773K have a low relative average deviation,which is less than 1%, compared with the calculation.
2020 Vol. 41 (6): 646-649 [Abstract] ( 262 ) HTML (1 KB)  PDF (1601 KB)  ( 659 )
650 Research on Calibration of Short Base Metal Thermocouples
WANG Zhe,YU Song-lin,SHEN Wen-jie,LI Qiang-guang,TIAN Yun,JIANG Jing
DOI: 10.3969/j.issn.1000-1158.2020.06.04
Short base metal thermocouples is a collective name,covering a kind of detachable base metal thermocouples with short electrode length(electrode length is 300~500mm) and base metal armored couples(length of metal sleeve is 300~500mm). Traditional measuring equipment and methods often fail to accurately measure the indication deviation in the high temperature region (above 300℃). The reason for the inaccuracy is found through experiments. The terminal thermostat is designed and developed to solve this problem and effectively reduce the extended uncertainty of the short-type even value deviation.
2020 Vol. 41 (6): 650-655 [Abstract] ( 303 ) HTML (1 KB)  PDF (1693 KB)  ( 374 )
656 Calculation of Base Station Coordinate for Tracking Interferometer with Gauss-Newton Algorithm Realized by C#
TANG Wen-xiu,LIN Hu,XUE Zi,QIN Hai-meng,TIE Mi-mi
DOI: 10.3969/j.issn.1000-1158.2020.06.05
In order to solve the base station coordinates for tracking interferometer with C# programming language, the calibration principle of the spatial coordinates of base station is studied. It is pointed out that the problem for calculation of base station coordinates will be turned into nonlinear least square problem in essence, so the Gauss-Newton algorithm is applied for solving this problem and its principle is analyzed. Furthermore, Gauss-Newton algorithm are realized by two programming methods: C# and MATLAB mixed programming, only by C# programming. The key technologies for these two programming methods are described in detail, the shortcomings of mixed programming are pointed out as well. The experimental system is established by the combination of a coordinate measuring machine and a laser tracking interferometer, and calibration experiments are carried out at three different base stations respectively. The experimental results show the difference between the result of C# programming and the result of C# calling MATLAB function is an amount of 10-7 orders of magnitude, and its more efficient, which verifies the calculation accuracy of base station coordinates for tracking interferometer with Gauss-Newton algorithm implemented by C#, and this lays a foundation for the subsequent development of the data acquisition and processing software of the laser tracking interferometer.
2020 Vol. 41 (6): 656-661 [Abstract] ( 347 ) HTML (1 KB)  PDF (555 KB)  ( 238 )
662 An Improved Method for NURBS Quadric Surface Based on Discrete Stationary Wavelet Transform
TIAN Xiao-qiang,KONG Ling-fu,KONG De-ming,CUI Yong-qiang
DOI: 10.3969/j.issn.1000-1158.2020.06.06
In order to improve fitting accuracy of quadric surface,an improved method for the currently recognized NURBS quadric surface method based on discrete stationary wavelet transform was proposed. At first, elevation image of the quadric surface point cloud and elevation sequence were obtained by using the grid method. Then feature points of the quadric surface were extracted from the discrete stationary wavelet transform results of the elevation sequence of the elevation image. Finally, high accuracy NURBS quadric surface was realized by using the extracted feature points. The experimental results showed that compared with NURBS method, the root mean squared errors of fitting results of sphere and cone surface were reduced 55.79% and 50.47% respectively, and it had satisfactory fitting precision.
2020 Vol. 41 (6): 662-668 [Abstract] ( 324 ) HTML (1 KB)  PDF (2377 KB)  ( 276 )
669 Study on Improved Sierra Dithering Algorithm for Micro-defocusing Projector Three-dimensional Profile Measurement Technology
WEI Xiao-hua,XU Wen-jun,XU Xue-ya
DOI: 10.3969/j.issn.1000-1158.2020.06.07
The traditional frequency modulation of the phase profile measurement techniqueis is analyzed. Combining with the micro-defocusing projection, the improved Sierra dithering algorithm is proposed using these quentially scanning to reduce binarization of sinusoidal grating quantization error and inhibition of asymmetric texture, this method can greatly improve the sinusoidality of the defocused fringe the pattern. The defocus grating is generated using the improved algorithm for three-dimension alprofile measurement technology, comparing with the Bayer ordered dithering algorithm, the Sierra dithering algorithm and the Floyd-steinberg error diffusion dithering algorithm, the experimental results show that the improved Sierra dithering algorithm has better adaptability, it can greatly reduce the phase error and faster calculation speed, accurate generated grating, and phase quality have then improved greatly, it is suitable for high precision three-dimensional profile measurement technology.
2020 Vol. 41 (6): 669-675 [Abstract] ( 262 ) HTML (1 KB)  PDF (3236 KB)  ( 353 )
676 A research on correction method of nonlinear errors for homodyne laser interferometer
JIN Tao,TANG Yi-kui,LE Yan-fen,LIU Fang-fang,LEI Li-hua
A kind of Heydemann correction method by minimizing the geometric distance is proposed for elimination the nonlinear errors of a single frequency laser interferometer in the displacement measurement. The Jamin interferometer is used to make a verification experiment. Jamin interferometer is a homodyne interferometer which conducts a differential structure based on the plane mirror. The movement of measured object will make the interferometer output orthogonal signals shift with a phase difference of 90° which are both used for displacement correction of the Jamin interferometer and correction method proposed. The experiment results show that the goodness of fit of corrected displacement is similar with Jamin interferometers which nearly equals 1. Compared with the result of Jamin interferometer, the residual errors between the corrected displacement and the displacement of capacitive sensor are much smaller under the same driving condition of piezoelectric ceramics, correction accuracy is better than the result of Jamin interferometer.
2020 Vol. 41 (6): 676-681 [Abstract] ( 252 ) HTML (1 KB)  PDF (1518 KB)  ( 702 )
682 Logs End Detection and Statistics by Color Difference Clustering
TANG Hao,WANG Ke-jian,LI Xiao-ye,JIAN Wen-hao,GU Jian-cai
DOI: 10.3969/j.issn.1000-1158.2020.06.09
Logs end detection is disturbed by the natural environment. An end detection method for logs accumulation state in natural environment is introduced based on image processing technology. Segmentation of logs images into logs sections, pores and backgrounds by color difference clustering to remove background interference and extracting logs end, segmentation counting is performed using hierarchical opening operation and an improved watershed algorithm. The results show that the correct detection rate is 91.88%, the false detection rate is 5.08%, and the missed detection rate is 8.12% under the high interference environment of natural environment. The method satisfies the requirement for the identification and counting of logs.
2020 Vol. 41 (6): 682-688 [Abstract] ( 296 ) HTML (1 KB)  PDF (2173 KB)  ( 206 )
689 Research on Light Source Optimization of Microfiber Measurement and Recognition System Based on Micro-optical Imaging
ZHENG Zhi-yuan,YU Xiao-lei,LIU Zhen-lu,ZHAO Zhi-min
DOI: 10.3969/j.issn.1000-1158.2020.06.10
The illumination source of the microscopic optical imaging fiber recognition system has a great influence on the imaging quality. Due to the limited luminous power of a single LED light source and uneven light distribution on the illuminated surface, the micro-nano fiber (average diameter of monofilament 15~40μm) collected by the system was blurred, which affected the accuracy of measurement and recognition results. According to the optical characteristics of LED, the illumination source of the system was optimized. Three different LED planar light source arrays were designed. According to the expression of the illuminance of the LED array on the illuminated surface, the simulation showed the LED array. The illuminance distribution was verified by experiments. The image recognition process and the peak signal-to-noise ratio (PSNR) of the image parameters were evaluated for the images actually detected by the system, and the optimization results were given. The research results showed that the optimized LED planar light source array effectively solved the problem of unclear blur recognition of microfibril images caused by uneven illumination. The image of the fiber sample obtained after optimization was clear, which effectively improved the image quality of the system for detecting fiber samples, and this provided a new way for microfiber measurement identification and research.
2020 Vol. 41 (6): 689-695 [Abstract] ( 266 ) HTML (1 KB)  PDF (1433 KB)  ( 480 )
696 Study of Failure Mechanism of TiN Coatings by Micro-scratch Testing
LIU Ming,LI Shuo,GAO Cheng-hui
DOI: 10.3969/j.issn.1000-1158.2020.06.11
The failure process of TiN coating was studied by micro-scratch and scanning electron microscope, the mechanism of friction coefficient fluctuation was analyzed and the fracture toughness of the coating was evaluated. The results show that at low load stage, the TiN coating undergoes shear slip, and the edge of the scratch track appears from the reverse V-shaped crack to the parallel crack, and then to the forward V-shaped crack; as the normal load increases, the TiN coating undergoes stepwise spalling. Fluctuations in the coefficient of friction are mainly due to surface topography and coating failure, different loading methods have different friction coefficients. The fracture toughness of the TiN coating can be tested accurately with micro-scratches, which is consistent with the test results of the indentation fracture method and the finite element simulation method.
2020 Vol. 41 (6): 696-703 [Abstract] ( 273 ) HTML (1 KB)  PDF (1771 KB)  ( 434 )
704 Time Domain Integral Method for Vibration Test Based on Combined Simpson Integral
XU Xiao-hong,NI Chun-feng,YAN Xiao-qing
DOI: 10.3969/j.issn.1000-1158.2020.06.12
Aimed at the time domain integral problem for vibration test, a kind of combined Simpson integral method is presented. The vibration test data are divided into the odd sequence and the even sequence, and the integral calculation recursive formula for each point is drawn through combining Newton Leibniz formula and Simpson formula. The whole integral waveform consist of the two integral sequences. The verification test is carried out through the earthquake data provided by Matlab, and the result illustrates the effectiveness of the method. The method has high computing precision, its truncation error reach 4 order infinitesimal of sampling step, and is suitable for vibration test application.
2020 Vol. 41 (6): 704-709 [Abstract] ( 300 ) HTML (1 KB)  PDF (464 KB)  ( 588 )
710 Rolling Bearing Fault Diagnosis Based on Improved Adaptive Parameterless Empirical Wavelet Transform
LI Ji-meng,WANG Hui,LI Ming,YAO Xi-feng
DOI: 10.3969/j.issn.1000-1158.2020.06.13
In order to realize the effective extraction of rolling bearing fault periodic impulse features and solve the problem of Fourier spectral segmentation in empirical wavelet transform, an improved adaptive parameterless empirical wavelet transform method is proposed. First, adaptive segmentation of the Fourier spectrum is performed by adaptive parameterless empirical wavelet transform. Then, the spectral boundaries are combined by using the kurtosis index, and the filter banks are reconstructed to decompose the signal; finally, the component corresponding to the largest kurtosis value is selected to extract fault features by the Hilbert transform. The simulation and engineering application verify the effectiveness of the proposed method. The analysis results show that the performance of the proposed method is better than ensemble empirical model decomposition and the classical empirical wavelet transform.
2020 Vol. 41 (6): 710-716 [Abstract] ( 330 ) HTML (1 KB)  PDF (1602 KB)  ( 696 )
717 Fault Diagnosis Method of Rolling Bearing Based on Improved Variational Mode Decomposition
MENG Zong,Lü Meng,YIN Na,LI Jing
DOI: 10.3969/j.issn.1000-1158.2020.06.14
A fault diagnosis method for bearing fault signal with improved variational mode decomposition was proposed. Firstly, the improved singular value decomposition denoising method was used to denoise the signal, and then the signal was subjected to variational mode decomposition.By using the ratio of the sum of the energy of the component signal to the original signal energy, the decomposition effect of the variational mode decomposition was judged to find the optimal decomposition layer. And based on the correlation coefficient between the component signals, it was judged whether the component signal adjacent to the center frequency was from the same modulation portion in the signal. Finally, the fault characteristic frequency was found by the envelope spectrum of the main component, and the fault type was judged.The weak frequency characteristic information was successfully extracted by processing the simulated signal and the actual bearing fault signal, and the effectiveness of the method was verified.
2020 Vol. 41 (6): 717-723 [Abstract] ( 334 ) HTML (1 KB)  PDF (637 KB)  ( 745 )
724 Coal Volume Measurement of Belt Conveyor Based on Image Processing
WANG Gui-mei,LU Sheng-hui,LIU Jie-hui,YANG Li-jie
DOI: 10.3969/j.issn.1000-1158.2020.06.15
Real-time measurement of coal fluid volume on belt conveyor based on laser oblique shooting triangular ranging principle was studied. Firstly, image processing of laser lines collected by industrial cameras was carried out to obtain coal flow cross section. According to the characteristics of laser lines on coal flow surface, a laser line thinning algorithm which can greatly reduce the searching area was proposed. It was superior to the similar algorithms in running time and thinning effect. Linear interpolation was used to connect the broken lines and form a complete coal cross section by synthesizing the upper and lower contours. After that, a dynamic coal volume measurement model was established, and coal fluid volume was obtained by integration. Finally, experiments were carried out. The average time of acquisition and processing of single frame image was about 0.152 s, and the algorithm had good stability, which could meet the requirements of actual working conditions.
2020 Vol. 41 (6): 724-728 [Abstract] ( 317 ) HTML (1 KB)  PDF (605 KB)  ( 295 )
729 Numerical Simulation on Gas-liquid Two-phase Flow Field in the Horizontal-baffle Type Surge Tank and Study on the Flow Stability
YU Lu-jun,CAO Jiu-ying,MA Yu-ming,HOU Song-liang,ZHENG Hai-fu
DOI: 10.3969/j.issn.1000-1158.2020.06.16
It describes the computational study of horizontal-baffle type surge tank of the water flow standard facility based on the standard k-ε turbulence model and volume of fluid multiphase transient model.The PISO algorithm is used to discrete the control equation, and the inlet velocity pulsation is defined by the UDF. The key information of the surge tank is obtained, such as pressure field, velocity field, stream trace and so on. The simulation reveals the influence of inlet pulse frequency, volume ratio of gas to water and position of the vertical baffle plate on the flow stability, and the computational result is verified by the experiment.The calculated results show low frequency pulsation has a bad influence on stability, when the inlet pulse frequency is 5Hz, the best volume ratio of gas to water is about 1:3, and the preferable position of the vertical baffle is at the front 1/3 of the surge tank.The flow fluctuation coefficient is 0.058% with the best stable performance.
2020 Vol. 41 (6): 729-734 [Abstract] ( 284 ) HTML (1 KB)  PDF (1532 KB)  ( 471 )
735 Indirect Prediction Method of RUL for Lithium-ion Battery Based on GA-ELM
CHEN Ze-wang,LI Fu-sheng,LIN Ya,YANG Ke,WANG You-ren
DOI: 10.3969/j.issn.1000-1158.2020.06.17
Aiming at the problem that it is difficult to directly measure the capacity of the lithium-ion battery when the remaining useful life(RUL)of the battery is predicted and the prediction result is inaccurate, an indirect prediction method was proposed. First, after fully analyzing the parameters of battery life sates, the equivalent voltage drop discharge time was chosen as the indirect health index of the battery. Secondly, genetic algorithm was introduced to optimize the extreme learning machine parameters to establish an indirect RUL prediction model for lithium-ion battery. Finally, the correctness of the GA-ELM method was verified based on NASA data and independent experimental data. The results showed, compared with the ELM method and Gaussian process regression method, this new method is accurate and effective, with high predicting speed, and its output is stable.
2020 Vol. 41 (6): 735-742 [Abstract] ( 318 ) HTML (1 KB)  PDF (2081 KB)  ( 722 )
743 Study on the Quality Control for Computed-tomography Simulators Based on JJG1086-2018
GAO Xiang,SHI Li-wan,FU Li-rong,CHEN Si-jia,LIU Jun,HE Yi-peng,CHEN Si-jia
DOI: 10.3969/j.issn.1000-1158.2020.06.18
The accuracy of the beam ray and the target area together with the accuracy of the patients positioning are more and more important in the emphasis on the accurate radiotherapy. One of the most important aspects is the scanning accuracy of CT and the quality of the images, so the quality control of positioning CT is related to the success of the whole radiotherapy process. The principles and methods of the X-ray radiation source of JJG (Min)1086-2018 X-ray radiation source in the verification and quality control were introduced in detail, and the quality control of the CT simulation machine was quantitatively analyzed from the aspects of the image quality and the machines mechanical precision. The measurement error of CT is less than 30HU, the image uniformity is less than 5.0HU, the resolution is 7Lp/cm, and the low contrast resolution is less than 3.0mm, 5.0mm and 6.0mm at 1.0%, 0.5% and 0.3% respectively, which meets the requirements of the regulations. The image quality and mechanical accuracy of CT simulator are well guaranteed. The dose accuracy, image parameters and position accuracy of CT simulator can be followed regularly.
2020 Vol. 41 (6): 743-747 [Abstract] ( 343 ) HTML (1 KB)  PDF (1045 KB)  ( 314 )
748 Prediction of Diesel Cetane Number Based on Power Index Method
WANG Jia-xing,ZHANG Hui-cheng,LING Feng-xiang
DOI: 10.3969/j.issn.1000-1158.2020.06.19
In order to realize the rapid detection of cetane number and reduce the usage of standard fuel, a mathematical model for predicting cetane number was established by using the power index method, and the cetane number calculated by the power index method was compared with the measured cetane number. The maximum prediction error of different kinds of diesel oil was obtained by predicting diesel oil with different compositions. The diesel oil type with high matching degree with the prediction model was found. Carry out targeted cetane number prediction. At the same time, the correction of prediction model results was proposed. The accuracy of power exponent fitting method can be further improved by correction, and the correction coefficient k is 0.991 when cetane number is 45. Power index method can reduce the usage of standard fuel samples, and the bench test cost is correspondingly reduced.
2020 Vol. 41 (6): 748-751 [Abstract] ( 283 ) HTML (1 KB)  PDF (697 KB)  ( 174 )
752 Detection of SO2 Based on EEMD Optimized by Wavelet
WANG Zhi-fang,WANG Shu-tao,WANG Gui-chuan,CHE Xian-ge
DOI: 10.3969/j.issn.1000-1158.2020.06.20
In order to solve the problem that SO2 fluorescence signals was faint and always cannot be distinguished with noises, a novel method based on wavelet optimization ensemble empirical mode decomposition (EEMD) was proposed. The SO2 detection system had been built. Using the SO2 detection system, SO2 concentration can be detected. The average error of detection was 0.0011, and the correlation coefficients between SO2 concentration and the fluorescence intensity was 0.9787. Wavelet optimization EEMD denoising method were applied to SO2 detection system, the results showed that the signal noise ratio(SNR) was 224.7958, the mean squared error(MSE) was 1.01×10-7, and the normalized correlation coefficient(NCC) was 0.9973. The correlation coefficients between SO2 concentration and fluorescence intensity was 0.9936. Compared with the wavelet denoising method and EEMD denoising method, the wavelet optimization EEMD method has the best denoising effect. The proposed method is superior to wavelet denoising method and EEMD denoising method.
2020 Vol. 41 (6): 752-758 [Abstract] ( 274 ) HTML (1 KB)  PDF (2491 KB)  ( 307 )
759 Experimental Study on Denoising of Ozone Concentration Signal by Differential Absorption Spectroscopy
ZHENG Hai-ming,LIU Jia
DOI: 10.3969/j.issn.1000-1158.2020.06.21
An experimental study on denoising of ozone concentration signal measured by differential absorption spectroscopy was presented. Common denoising methods are wavelet transform, Savitzky-Golay filtering and Fourier transform filtering. Firstly, the three kinds of filtering methods were used to denoise the absorption spectra of ozone respectively, and the absorption spectra after denoising were obtained. It was found that the wavelet transform and Savitzky-Golay filter can fit the feature absorption well, and the Fourier transform filter was slightly worse. Then, the obtained spectrum was analyzed and evaluated by using the signal-to-noise ratio and the root mean square error. The experimental results showed that Savitzky-Golay filtering has the best effect on signal denoising and can be applied preferentially to the spectrometric analysis of ozone.
2020 Vol. 41 (6): 759-764 [Abstract] ( 229 ) HTML (1 KB)  PDF (1376 KB)  ( 326 )
765 A Calibration Method for Mass Concentration of Aerosol Photometers
ZHANG Ai-liang, LIU Yue, CHEN Qi-yue, WANG Ting-ting, SHI Chan-zhen, ZHANG Zi-tong
DOI: 10.3969/j.issn.1000-1158.2020.06.22
The internal mechanism and working principle of aerosol photometer are introduced. Based on filter membrane sampling method, device of the mass concentration calibration and method of aerosol photometer are proposed. The fogging concentration of aerosol fogging device, whose stability is less than 5%, is verified by experiments. The aerosol photometric mass concentration error is less than ±10%. The traceability of the mass concentration of the aerosol photometer is solved, which can effectively improve the measurement accuracy of the device.
2020 Vol. 41 (6): 765-768 [Abstract] ( 326 ) HTML (1 KB)  PDF (1011 KB)  ( 332 )
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