Table of Content

25 February 2023, Volume 51 Issue 2

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2023, 51(2):  0. 

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Mechanical Engineering

LiDAR-Binocular Camera Calibration by Minimizing LiDAR Isotropic Error



CHEN Zhong, LIU Zichen, ZHANG Xianmin

2023, 51(2):  1-9.  doi:10.12141/j.issn.1000-565X.220178

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Multi-modal data fusion of LiDAR (Laser Imaging, Detection, and Ranging) and binocular camera is important in the research on 3D reconstruction. The two sensors have their own advantages and disadvantages, and they can complement each other through data fusion to obtain better reconstruction results. In order to achieve data fusion, firstly it is necessary to unify the two data into the same coordinate system. The calibration results of the external parameters between the LiDAR and the camera are very important to 3D reconstruction. Due to sparse LiDAR point cloud and its positioning error, it is a challenge to extract feature points accurately for constructing accurate point correspondences when calibrating extrinsic parameters between LiDAR and stereo camera. In addition, most calibration methods ignore that LiDAR works on spherical coordinate system and directly use the Cartesian coordinate measurement results for calibration, which introduces anisotropic coordinates error and reduces the calibration accuracy. This paper proposed a calibration method by minimizing isotropic spherical coordinate error. Firstly, a novel calibration object using centroid feature points was proposed to improve the extraction accuracy of feature points. Secondly, the anisotropic LiDAR Cartesian coordinate error were convert into the isotropic spherical coordinate error, and the extrinsic parameters were solved through directly minimizing the spherical coordinate error. The experiments show that the proposed method has advantages over the anisotropic weighting method. The method ensures that the solution is globally optimal and the number of calibration samples required is greatly reduced on the premise of sacrificing some accuracy. With the optimal calibration error of 2.75 mm, the amount of calibration data can be reduced by about 54.5% by sacrificing 3.6% accuracy using the proposed method.

Multi-field Coupling Vibration and Signal Analysis of Cross Microresonator



HAN Guang, XU Lizhong

2023, 51(2):  10-19.  doi:10.12141/j.issn.1000-565X.220210

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Micro-Electro-Mechanical System (MEMS), also known as microsystem or micro-electro-mechanical system, is a high-tech micro device or system developed on the basis of microelectronic technology. MEMS integrates photolithography, corrosion, LIGA, silicon and non-silicon surface micromachining, precision machining and other technologies, and its size is on the micron scale. The microsensors produced by micromachining technology are widely used in engineering practice because of their simple structure, high sensitivity and stable operation. The microsensor usually uses electrostatic excitation and capacitance detection to detect the signal, that is, the displacement change of the resonator during vibration leads to the change of the distance between two electrodes, so as to change the capacitance between electrodes, thus the detected capacitance change frequency is the frequency of resonantor vibration. A cross microresonator was proposed to solve the problem of weak capacitance signal and low detection accuracy of microsensor. To study the multi-field coupling effect of microresonator, the multi-field coupling nonlinear dynamics equation of harmonic oscillator was established considering Van der Waals force and electric field force. The dynamic displacement of nonlinear vibration was obtained by using Linz Ted-Poincare method, and the influence of multiple physical field parameters on mean vibration displacement and capacitance variation of the harmonic oscillator was analyzed. The cross microresonator was fabricated by micro-nano machining, and the capacitance variation resulted from resonant frequency and vibration displacement was measured by electrostatic excitation-capacitance detection method. The results show that the cross microsensor increases the plate area, thereby aggrandizing the capacitance variation, and thus the signal intensity becomes stronger. When the plate area increases by 75%, the capacitance change is 4.2 times of the original, and the signal intensity increases by 5.0 times, so it is more convenient for capacitance detection.

Three-Parameter Estimation of the Weibull Distribution Based on Least Squares Iteration



YANG Xiaoyu, SONG Jiaxin, XIE Liyang, et al

2023, 51(2):  20-26.  doi:10.12141/j.issn.1000-565X.220231

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The three-parameter Weibull distribution is widely used to describe product longevity because of the convenience and adaptability of its mathematical processing. The three-parameter Weibull distribution with location parameter is one of the most suitable models for studying the reliability of mechanical components, especially for long-life and high-reliability products. Parameter estimation of three-parameter Weibull distribution has always been the focus of attention. This paper proposed an iterative method based on least squares to estimate the parameters of the three-parameter Weibull distribution. The initial location parameter was set to 0, the initial shape parameter and scale parameter were obtained by using least squares, and the new location parameter was obtained by substituting them into the unbiased estimation of the location parameter, and multiple iterations were performed. In this process, the shape parameters and scale parameters gradually become smaller and the location parameters gradually become larger, and finally the stable shape parameters, scale parameters and location parameters were obtained, which are the final parameter estimates, and the lifetime of 99% reliability was calculated. The method was proved to be convergent by Monte Carlo simulation. Compared with the correlation coefficient method by two metrics including Bias and Root Mean Square Error (RMSE) for different Weibull models with different small and medium sample sizes (10, 15, 20, 25 and 30), the three estimated parameters and the 99% reliability of the lifetime of the proposed method are more accurate. The analysis of two examples shows that the method is feasible and valid. Compared with the correlation coefficient method, the estimation results are more conservative and more suitable for engineering application.

Study on the Morphology Control Technology of Spray Forming Ingot Billets Based on GA-BP Neural Network



LENG Sheng, FU Youwei, MA Wantai, et al

2023, 51(2):  27-34.  doi:10.12141/j.issn.1000-565X.220147

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With the development of modern technology, the automotive and aerospace fields are pursuing the lightweight of materials, and the high strength and high toughness of materials is the basis of lightweight. 7000 series aluminum alloys (Al-Zn-Mg-Cu series aluminum alloys) have the advantages of high strength, high hardness, good corrosion resistance, et al. Among all aluminum alloys, 7055 aluminum alloy has the highest strength. The common preparation method of 7055 aluminum alloy is spray forming process. Stable growth of the aluminum ingot during deposition is the basis for the preparation of large-size ingots with uniform deposition quality by the spray forming process. Due to the variation of numerous process parameters during the jet forming process, the existing theoretical model is difficult to meet the requirements of quality control in the actual production process. This paper built a GA-BP neural network prediction model for the diameter and a model for regulating the growth rate of the ingot billet based on the correlation analysis between the historical data of the injection molding process and the diameter of the deposited surface of the ingot billet, by combining BP neural network and genetic algorithm. Based on the real-time fluctuation of process parameters, the diameter variation was calculated and used as an input layer into a trained velocity regulation neural network model to optimally regulate the lifting speed of the deposition substrate, resulting in a uniform and stable deposition growth profile of the ingotst. Finally, this method was used to regulate the growth rate of ingots. The results show that the deviation of large-size ingot diameter is within 5%, which verifies the feasibility of growth rate regulation.

Hardness Prediction of TC4 Machined Surface Based on the Evolution of Multi-scale Grain Refinement



WANG Qingqing, LIU Zhanqiang, CHENG Yanhai, et al

2023, 51(2):  35-46.  doi:10.12141/j.issn.1000-565X.220181

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The microstructure variations of machined surface determine the performance of machined components. Accurately predicting the microstructure evolution of machined surface and thus enhancing surface hardness of machined components is an effective way to improve the service performance and realize the controllable machining of components. Machining is one the fundamental manufacturing techniques of TC4 components and the severe plastic deformation during machining process induces the complex evolutions of microstructure for TC4 machined surface. For the grain refinement phenomenon during TC4 cutting, this paper studied the multi-scale distribution characteristics of microstructure, evolution mechanisms of grain refinement and its effect on the material hardness under different cutting speeds (100 ~ 500 m/min). The results show that grain refinement degree at meso-scale (10^-6 ~ 10^-5 m) increases first and then decreases with the increasing of cutting speed. At cutting speed of 300 m/min, grain refinement degree of machined surface is 69.7% and the grains in the shear bands of chips are refined to 2 ~ 6 μm. Complex dislocation patterns and nano twining are the features of microstructure at micro-scale (10^-8 ~ 10^-7 m). The deformation twinning type is mainly characterized as {10\bar{\mathrm{1}}1} compression twinning and it is generated at higher cutting speed (> 200 m/min). Grain refinement during machining of TC4 was predicted based on the modified Z-H grain refinement model and nano twining volume fraction prediction model. The hardening effect of grain refinement was also considered in the prediction model. The evolution of grain sizes and the work hardening was predicted. The relation between grain refinement and material hardness was established, and the hardness of TC4 machined surface was predicted with directional controlling the grain refinement degree and formation of nano twinning. And the hardening mechanism in micro-scale of TC4 machined surface was revealed.

Thermodynamic Analysis of Low Temperature Differential Stirling Engine



WU Shangsheng, HUANG Tiexiang

2023, 51(2):  47-53.  doi:10.12141/j.issn.1000-565X.220136

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The traditional analysis method is not practical in the power prediction and parameter optimization analysis of low temperature differential Stirling engine. In order to predict the output power of low temperature differential Stirling engine quickly, this paper studied the application of the second order Simple model in the thermodynamic cycle analysis of low temperature differential Stirling engine. It described the simplified structural model of low temperature differential Stirling engine and the temperature characteristics of internal working medium. Based on Simple model, this study derived the actual heat transfer equation of non-ideal heat exchanger in low-temperature differential Stirling engine, and analyzed the heat return loss, pumping loss and actual heat transfer of heat exchanger. The variation of the temperature, pressure and energy of the working medium in the low-temperature differential Stirling engine system with the crank Angle was illustrated by examples, and the theoretical output power of the low-temperature differential Stirling engine was analyzed. The actual output power of low temperature differential Stirling engine at different heating temperatures was compared with the calculated power of Simple model. The comparison results show that the error between the output power calculated by the Simple model and the actual output power is small, indicating that the Simple model is in good agreement with the actual cycle of the low-temperature differential Stirling engine. In order to study the influence of regenerator on engine performance of low temperature difference Stirling engine, the paper optimized the structure of regenerator of low temperature difference Stirling engine. The output power of the regenerator after optimization was compared with that before optimization. The comparison results show that after optimizing the regenerator, the actual output power of the low-temperature differential Stirling engine and the calculated power of the Simple model are both increased by 20%. It is shown that optimizing the structure of regenerator is an effective method to improve the performance of low temperature differential Stirling engine.

Traffic & Transportation Engineering

Transient Aerodynamic Characteristics of Train Exiting from Bridge Tunnel Area Under Cross Wind



MAO Jun, HAN Chenyu, CHEN Minggao

2023, 51(2):  54-64.  doi:10.12141/j.issn.1000-565X.220198

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In this paper, a cross-wind-train-bridge-tunnel model was established to conduct simulation calculation based on the unsteady characteristics of flow field under cross-wind action of high-speed trains. The accuracy of the numerical method was verified by 1∶8 dynamic model test. Then, the transient aerodynamic pressure, aerodynamic load changes and flow field characteristics inside and outside the tunnel were studied when the train broke out of the tunnel under cross-wind conditions, so as to reveal the interaction mechanism between cross-wind, train, bridge and tunnel. The results show that the pressure decreases gradually with the increase of cross wind speed, and the change law of pressure with time is similar. The cross wind has an obvious effect on the pressure gradient at the exit of the tunnel and outside the tunnel, but has almost no effect on the measuring point inside the tunnel. With the increase of cross wind speed, the peak value of the positive pressure on the leeward side outside the tunnel decreases slightly with the increase of wind speed, while the peak value of the positive pressure on the windward side basically remains unchanged. And the decrease rate of the peak value of the negative pressure on the leeward side is greater than that on the windward side. The cross wind has limited influence on the pressure fluctuation of train protruded tunnel. When the cross wind speed is 20 m/s, the scope of influence of the external flow field on the pneumatic pressure in the tunnel is less than 20 m. Under the same cross-wind condition, the pressure time-history variation rules at the measuring points on the windward side and the leeward side are different, and the position of the peak value of the pressure gradient is also different. The closer the measuring points on the same side of the train are to the ground, the greater the peak value and the absolute value of the peak value of the pressure gradient are. Under cross wind, when the airflow passes through the vehicle-bridge system, obvious flow separation occurs at the bottom of the bridge, the top and bottom of the leeward side of the train, resulting in the pressure difference on both sides of the train outside the tunnel is greater than that on both sides of the train inside the tunnel.

Structure Evolution Law of Soil-Rock Mixture Fillers with Different Gradations Under Seepage



MAO Xuesong, WANG Yueyue, WU Qian, et al

2023, 51(2):  65-75.  doi:10.12141/j.issn.1000-565X.220203

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Seepage is a key factor that causes the loss of fine particles in soil-rock mixture fillers and leads to changes in soil structure and subgrade deformation and instability. In this paper, the self-developed particle loss test device was used to carry out the seepage test of soil-rock mixture fillers with different gradations. The change process of permeable quality, fine particle loss and settlement of fillers under seepage was monitored, and the evolution process of soil structure was analyzed. Particle Flow Code in 3D (PFC^3D) was used to simulate the process of fine particle loss, and the dynamic change characteristics of soil porosity and filler particle size were analyzed. The results show that the permeability quality and fine particles loss rate can reflect the sensitivity of soil-rock mixture fillers structure to water. The lower the sensitivity of filler skeleton structure to water, the less the damage of the seepage to the structure, because the water can be discharged timely and effectively. The structural evolution process of soil-rock mixture fillers under seepage conditions can be divided into three stages, namely, stage of rapid loss of fine particles, skeleton remodeling stage, and relatively stable stage. The skeleton remodeling stage is the key stage to cause structural damage. In the stage of rapid loss of fine particles, the growth rate of per hour permeable quality is fast, a large number of fine particles are lost, and the settlement is small. In the skeleton remodeling stage, the change rate of per hour permeable quality slows down, and the loss of fine particles decreases. However, the reorganization of skeleton structure leads to obvious relative displacement of particles, and the settlement increases rapidly. In the relatively stable stage, the per hour permeable quality changes slowly and the settlement remains basically unchanged. The process of particle loss numerical simulation shows that the migration of fine particles causes the change of porosity of fillers, resulting in the change of soil structure. The results show that, among the studied fillers, the soil-rock mixture fillers with n=0.55 has the most stable skeleton structure and the weakest sensitivity to water.

Calculation of Elastic Stiffness of Shear Connector in Steel Concrete Bridge Tower Joint Section



DU Yunwei, WANG Ronghui, ZHEN Xiaoxia, et al

2023, 51(2):  76-87.  doi:10.12141/j.issn.1000-565X.220253

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For the research on the mechanical properties of single perforated plate connector or shear stud connector, international scholars have carried out a lot of numerical analysis and experimental exploration, and obtained the mechanical behavior of single perforated plate connector or shear stud connector. However, the interior of the steel-concrete composite section of the actual hybrid bridge tower is composed of a large number of perforated plate connectors and shear stud connectors. At present, the research on composite connectors in steel-concrete structures is relatively scarce, and there is no clear numerical model and theoretical derivation to study the force transfer law of composite connectors. And the influence of the design parameters of the composite connector itself on the compressive performance also needs to be further clarified. Therefore, taking a composite shear connector in the steel-concrete composite section of the bridge tower of Shunde bridge as an example, this paper studied the contributions of the perforated plate connector and the shear stud connector to the compressive stiffness of the single-layer composite shear connector during the elastic loading stage. Then it established the spring model and derived the formula for calculating the elastic stiffness of the single-layer composite shear connector. Using ABAQUS finite element software, the load simulation analysis of single-layer composite shear connectors was carried out. In the elastic loading stage, the load displacement curve shows a strong linear relationship. After fitting, the results are compared with the elastic stiffness calculation results of the derived formula. The results show that the error between the analytical solution and the numerical solution of the compressive stiffness of the single hole perforated plate connector is 4.87%, the error between the analytical solution and the numerical solution of the compressive stiffness of the single shear stud connector is 0.903%, and the error between the analytical solution and the numerical solution of the compressive stiffness of the single-layer composite shear connector is 11.54%. The calculated results of the derived elastic stiffness formula are in good agreement with the results of the finite element simulation analysis.

Automated Extraction of Road Geometry Information Using Mobile LiDAR Point Cloud



YU Bin, ZHANG Yuqin, WANG Yuchen, et al

2023, 51(2):  88-99.  doi:10.12141/j.issn.1000-565X.220459

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To efficiently collect and digitally model road facility information, this paper constructed a method framework for automatic extraction of road geometry information by using vehicle-mounted laser point cloud data. For the disorder and redundancy of laser data, grid drop sampling and radius filtering were used to simplify the size of the point cloud and remove noise points. The point cloud is organized and indexed by grid cell division, and the spatial locality of the point cloud is rationally utilized to reduce the scale of operation. Using the hierarchy of road elements on elevation and the continuity and smoothness of pavement structure, elevation filtering, local normal vector filtering based on the principal component analysis framework, and DBSCAN clustering methods were designed to achieve accurate segmentation from the original point cloud to the pavement point cloud. The road direction was obtained by collecting vehicle trajectory information, and the road cross section was divided by its direction vector and normal vector. The cross-section was cut and projected onto a two-dimensional plane, and the road width and horizontal and horizontal parameters were extracted by sliding window and least square algorithm. By comparing the extraction algorithm with the manual measurement results, in the two experimental data sets of complex blocks and suburban roads, the accuracy of point cloud segmentation is more than 87%, the integrity is more than 97%, and the extraction quality is more than 86%. The average relative error of geometric information is small, indicating that the algorithm has good extraction quality. Under the condition of finite computation, the processing time of two data centralized point clouds is 6.864 and 10.078 s/km, respectively, and the extraction time of geometric information is 1.732 and 0.843 s/km, respectively. The proposed method can give a good balance between extraction efficiency and accuracy, and has good applicability in complex blocks and suburban highway environments. It can provide a reference for the health assessment and three-dimensional reconstruction of road facilities.

Research on the Non-linear Relationship Between Built Environment and Bike-sharing Flow Rate



LU Qingchang, XU Biao, CUI Xin

2023, 51(2):  100-110.  doi:10.12141/j.issn.1000-565X.220141

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The bike-sharing(BS) flow rate reflect the degree of surplus and shortage of vehicles in urban spatial environment. Understanding its changes and incentives is of great significance for urban BS scheduling. Due to the complexity and variability of travel purposes and external environmental factors, it is difficult to analyze the relationship between the BS flow rate and the characteristics of the built environment through a statistical model with linear assumptions. Therefore, this study explored the contribution of the built environment to the BS flow rate and the nonlinear effects on the flow rate, as well as the changes of the nonlinear model of the BS flow rate on weekdays and weekends based on the data of BS in the downtown of Shanghai, through the extreme gradient boosting tree model (XGBoost) and the interpretive method partial dependence plot (PDP) of machine learning. The results show that the feature importance and nonlinear mechanism are significantly different in the two periods. The density of residential population, educational facilities and residential facilities has a high degree of explanation for the weekday BS flow rate, which is 19.18%, 13.16% and 12.92%, respectively, and has a significant threshold effect. The density of residential population and the density of educational facilities have a positive impact on the net BS outflow rate, reaching the maximum at 11 600 person per km² and 8 educational facilities per km² respectively; the density of residential facilities has a negative impact on the net BS outflow rate, and the corresponding threshold is 40 residential facilities per km².There is little difference in the explanatory degree of each variable to weekend BS flow rate, nevertheless the nonlinear relationship cannot be ignored. Specifically, the distance to the city center and bus line number density have a significant positive impact on the weekend net BS inflow rate, with the effective range of 18~23 km and 28~52 routes per km². The positive influence range of plot ratio on net BS outflow rate at weekends is 0.89~1.41. The above findings show that XGBoost model can effectively compensate for the bias of linear assumption of traditional regression model (MLR), and the disclosure of the contribution degree and influence scope of built environment characteristics also provides decision-making suggestions for the management department for BS dispatching in areas with different built environment levels.

Development Law of Traffic Network Density in the Spatial Structure of Metropolitan Area Hierarchy



WU Jiaorong, HUANG Zhengwen, DENG Yongqi

2023, 51(2):  111-121.  doi:10.12141/j.issn.1000-565X.220159

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During the "14th Five-Year Plan" period, China has entered a new stage of urbanization development. Cultivating modern metropolitan areas is an efficient approach to promote the development of urban agglomerations. Rapid transportation systems such as expressways and high-speed railways in the regional transportation network are the precondition for the formation and development of metropolitan areas. The regional heterogeneous spatiotemporal convergence effects caused by them profoundly affect the spatial pattern of metropolitan areas. Therefore, there is a urgent need to examine the interactive relationship between the spatial organization of metropolitan areas and different transportation network levels. In order to explore the development law of spatial variations on expressway and railway density caused by the dislocation of population aggregation and economic development in metropolitan area hierarchy, this paper constructed a city correlation strength model based on multi-source data. It took five metropolitan areas in the Yangtze River Delta urban agglomeration as examples and districts and counties as spatial units. Multidimensional scaling analysis and spatial distance elements were applied to identify the boundaries of the metropolitan area hierarchy, namely boundaries of core circle, tight circle, and planning range. Based on the five main indicators of population density, per capita GDP, land output rate, railway density, expressway density in each metropolitan area hierarchy, this paper discovered the correlation law between socioeconomic development and transportation network density. Results show that there are unbalanced population agglomeration and economic development in each circle of the metropolitan area, and the development curves of "population density-output per land" and "output per land-output per capita" are "S-shaped" and "logarithmic", respectively; the development laws of "population density-expressway density" and "land output rate-expressway density" both show a "logarithmic" curve, but those of the current railway density curves vary from those of expressway; when the population density is higher than 600 people/km2 and the land output rate is more than 80 million yuan/km2, the railway density in the core circle is insufficient. This study provides a new perspective for the research on integrated transportation network planning in the metropolitan area.

Physics

Statistical Voronoi Model for Monodisperse Disk Packings



ZHANG Xinggang, DAI Dan, TANG Yan

2023, 51(2):  122-130.  doi:10.12141/j.issn.1000-565X.220340

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It is of great significance to study the geometric structure and characteristics of random packings for understanding the macroscopic physical properties of disordered systems such as granular matter, foam, colloid, etc. Combining with experiments and computer simulations, researchers have explored the random packings of particles with different shapes and dimensions. In theory, some models based on statistical geometry, mean field approximation or stochastic process were proposed to investigate the volume fraction and average coordination number of random packings. However, due to the complex constraints of packing structure, the difficulty of setting a criterion for the disorder, etc., it is difficult to perform rigorous analysis and calculation even for monodisperse disk packings. For the volume fraction of the random closed packing, different studies provided different results. In this paper，a statistical Voronoi model was proposed for the theoretical research of the geometric properties of the monodisperse disk packings. The Voronoi network was used to describe the configuration of a packing and an area formula of the Voronoi network was deduced for general case. Based on the concepts of excluded circle and Voronoi circle, several theorems were given for determining the Voronoi nearest neighbor relationship between rigid disks. For balanced and stable disk packings, based on the relationships between the features of a Voronoi cell and the contact structure of nearest neighbor disks, this paper derived several formulae such as the volume fraction of a symmetric Voronoi cell varying with the contact number, the area of a Voronoi cell and the geometric coordination number varying with angles of neighbor contact lines. Finally, this paper derived the integral formulae for the average geometric coordination number and the average reduced free volume with respect to the probability distribution of the contact line angle by using the statistical analysis of Voronoi network. Theoretical calculation results show that the volume fraction of a Voronoi cell increases both with the increase of its symmetry and its contact number, the average contact number is 4 and the average volume fraction is π²/12 for the random closed packing. These results can be used to understand the geometric structure and feature of the frictionless disk packing.

Vapor Pressure and Equilibrium Radius of Dielectric Spherical Droplet Under Electrostatic Field



HAN Guangze, CHEN Junyan

2023, 51(2):  131-136.  doi:10.12141/j.issn.1000-565X.220007

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The condensation or evaporation of droplet is a phase change process, which is not only an efficient heat and mass transfer process, but also has a close relation with the change of the environmental climate. Experimental results show that the electrostatic field has a big influence on the formation of droplet, and it is an effective way to enhance heat and mass transfer and it’s also related to the formation of lightning and rain. Based on the phase equilibrium theory, this paper derived the mathematical expressions of pressure difference, vapor pressure and equilibrium radius of spherical dielectric droplet under electrostatic field by using the thermodynamic equations with the effects of electric field. By means of numerical calculations, it analyzed the formation process of droplet with these mathematical expressions. The results show that the pressure difference, vapor pressure and equilibrium radius of dielectric droplet under electrostatic field are increased compared with those without electric field. The increase of vapor pressure and equilibrium radius will accelerate the evaporation process of droplet, so the electrostatic field can promote the evaporation of droplet. This conclusion is consistent with the experiments and can provide reference for related theoretical researches and engineering applications.

On Aero-optical Effect and Control of Supersonic Boundary Layer



TIAN Lifeng, GUO Meiqi, DING Hao, et al

2023, 51(2):  137-146.  doi:10.12141/j.issn.1000-565X.220390

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Optical imaging detection technology is an important subject in the study of precision guided weapons. The aero-optical effects has a big influence on the guidance precision, and it can make the vehicle off the target position, or even off the target. The interaction between the aircraft and the incoming flow leads to a very complex flow field structure around it. The existence of shock waves, expansion waves and turbulent boundary layer makes the refractive index of the flow field unevenly distributed in space and high frequency jitter in time. Among them, the aero-optical distortion caused by the boundary layer rotation process is the biggest problem to be solved urgently. Boundary layer transition, as a process of boundary layer flow from laminar to turbulent state, is a strong nonlinear complex flow physical phenomenon influenced by multi-factor coupling, and has been a hot topic in turbulence research field.The transition region of the supersonic boundary layer is very unsteady and random, and the pulsation frequency is high, so the refractive index distribution is extremely complex. The light passing through this layer will be deflected, and there will be imaging blur and energy dispersion which seriously affect the accuracy of imaging guidance. It is difficult to reduce this effect by optical correction. This paper attempted to reduce or even eliminate the effect of supersonic boundary layer transition on optical transmission performance by delaying boundary layer transition. Taking the boundary layer flow field around the optical window of the supersonic rotary vehicle as the research object, the study carried out numerical simulation on the variation law of the aero-optical effect of the boundary layer by using the flow control method of adding perturbation plates. The results show that with the increase of the angle of attack, the distribution of optical path difference gradually changes from the symmetrical distribution along the symmetry plane to the change along the flow direction, and gradually flattens. After the turbulence control is applied, the transition position of the boundary layer above the optical window moves backward, and the flow field above the window gradually changes from the transition area to the laminar flow area, which has a significant effect on suppressing the aero-optical effect.