Xianjun Zheng, Tingyao Wu, Chaoyang Wu, Xiaoqin Wang
The dynamic response characteristics of the tunnel and the stability of the surrounding rock are crucial to its safety of the tunnel. Combining the numerical simulation software and field measurement results, the change of peak particle vibration (PPV) and stress were analyzed, based on the longitudinal wave data from the acoustic tests, the blasting damage effects under the action of different blasting counts, including different locations in the deep part of the surrounding rock, were investigated. The results show that: (1) in the vertical direction of the tunnel, the PPV of the tunnel floor and tunnel sidewall is larger, the PPV of the tunnel top is the second, and the tunnel arch shoulder and arch foot is the smallest; (2) under the action of blasting, the stress concentration at the tunnel bottom and arch foot is easier, and the stress monitoring should be strengthened; (3) The depth of damage at different distances was 1.5 m and 3.0 m, respectively, and the depth of damage to the surrounding rock increased from 2.5 m to 4.0 m when the number of blasts was 10 and the number of blasts was 10.
{"title":"Dynamic damage and response characteristics of the tunnel by FEM modeling and field trials","authors":"Xianjun Zheng, Tingyao Wu, Chaoyang Wu, Xiaoqin Wang","doi":"10.21595/jve.2023.23073","DOIUrl":"https://doi.org/10.21595/jve.2023.23073","url":null,"abstract":"The dynamic response characteristics of the tunnel and the stability of the surrounding rock are crucial to its safety of the tunnel. Combining the numerical simulation software and field measurement results, the change of peak particle vibration (PPV) and stress were analyzed, based on the longitudinal wave data from the acoustic tests, the blasting damage effects under the action of different blasting counts, including different locations in the deep part of the surrounding rock, were investigated. The results show that: (1) in the vertical direction of the tunnel, the PPV of the tunnel floor and tunnel sidewall is larger, the PPV of the tunnel top is the second, and the tunnel arch shoulder and arch foot is the smallest; (2) under the action of blasting, the stress concentration at the tunnel bottom and arch foot is easier, and the stress monitoring should be strengthened; (3) The depth of damage at different distances was 1.5 m and 3.0 m, respectively, and the depth of damage to the surrounding rock increased from 2.5 m to 4.0 m when the number of blasts was 10 and the number of blasts was 10.","PeriodicalId":49956,"journal":{"name":"Journal of Vibroengineering","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48511450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fei Du, Nengyong Wang, T. Ma, Zhihao Zhang, Menghan Yin
In this paper, In order to make use of the rotating motion characteristics of the roller cage shoe structure in vertical shaft lifting guide device, a nonlinear gyromagnetic excitation piezoelectric superposition beam energy harvester with compact structure, non-contact and high energy harvester efficiency is designed. The nonlinear force between moving magnet and stationary magnet is used to transform the rotating motion of the roller cage shoe into the end vibration of the piezoelectric vibrator. In order to improve the utilization rate of the piezoelectric plate and the low-amplitude response sensitivity of the energy harvester, acrylic material is introduced to re-place the traditional metal substrate, the bottom piezoelectric vibrator is hinged with the end of the top piezoelectric vibrator, and the middle part of the piezoelectric vibrator ends are longitudinal-superimposed beam structure with chute connection. The structural parameters, gyromagnetic excitation properties and strength of the piezoelectric vibrator are optimized and analyzed through finite element simulation and experiments, and the longitudinal and transverse arrays of piezoelectric vibrators are designed. The effects of terminal connection mode, array spacing, array number and load resistance on the power generation performance of the energy harvester are investigated. The results show that when the number of vertical arrays is 8 layers and the array spacing is 1.5 mm, higher voltage output and vibration consistency are achieved. When the horizontal array is 7 groups and the load is 10 kΩ, the maximum output power of the energy harvester is 11.26 mW, which can realize the self-power supply to the wireless transmitting node.
{"title":"Research on performance of piezoelectric superimposed beam energy harvester under gyromagnetic excitation","authors":"Fei Du, Nengyong Wang, T. Ma, Zhihao Zhang, Menghan Yin","doi":"10.21595/jve.2023.22972","DOIUrl":"https://doi.org/10.21595/jve.2023.22972","url":null,"abstract":"In this paper, In order to make use of the rotating motion characteristics of the roller cage shoe structure in vertical shaft lifting guide device, a nonlinear gyromagnetic excitation piezoelectric superposition beam energy harvester with compact structure, non-contact and high energy harvester efficiency is designed. The nonlinear force between moving magnet and stationary magnet is used to transform the rotating motion of the roller cage shoe into the end vibration of the piezoelectric vibrator. In order to improve the utilization rate of the piezoelectric plate and the low-amplitude response sensitivity of the energy harvester, acrylic material is introduced to re-place the traditional metal substrate, the bottom piezoelectric vibrator is hinged with the end of the top piezoelectric vibrator, and the middle part of the piezoelectric vibrator ends are longitudinal-superimposed beam structure with chute connection. The structural parameters, gyromagnetic excitation properties and strength of the piezoelectric vibrator are optimized and analyzed through finite element simulation and experiments, and the longitudinal and transverse arrays of piezoelectric vibrators are designed. The effects of terminal connection mode, array spacing, array number and load resistance on the power generation performance of the energy harvester are investigated. The results show that when the number of vertical arrays is 8 layers and the array spacing is 1.5 mm, higher voltage output and vibration consistency are achieved. When the horizontal array is 7 groups and the load is 10 kΩ, the maximum output power of the energy harvester is 11.26 mW, which can realize the self-power supply to the wireless transmitting node.","PeriodicalId":49956,"journal":{"name":"Journal of Vibroengineering","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44724224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The current research investigates the prediction of piezoelectric damping of resistively shunted beams caused by resistors via joule heating. In order to maximize the extra damping of the piezoelectric shunted beam system, a sensitivity analysis was done. The geometrical impacts on the maximum additional damping simulation are investigated for different length and thickness ratios with the position of the PZT-5H from the base of the cantilever and simply supported beams. Prior to doing sensitivity analysis, a mathematical model for estimating extra damping from voltage produced. Validation experiments are also carried out.
{"title":"Sensitive analysis on added damping of shunted piezoceramic damping: cantilever and simply supported beam","authors":"K. GuruBrahmam, T. R. Rao, M. Chandra, S. Reddy","doi":"10.21595/jve.2022.22858","DOIUrl":"https://doi.org/10.21595/jve.2022.22858","url":null,"abstract":"The current research investigates the prediction of piezoelectric damping of resistively shunted beams caused by resistors via joule heating. In order to maximize the extra damping of the piezoelectric shunted beam system, a sensitivity analysis was done. The geometrical impacts on the maximum additional damping simulation are investigated for different length and thickness ratios with the position of the PZT-5H from the base of the cantilever and simply supported beams. Prior to doing sensitivity analysis, a mathematical model for estimating extra damping from voltage produced. Validation experiments are also carried out.","PeriodicalId":49956,"journal":{"name":"Journal of Vibroengineering","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47210413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The friction vibration signal corresponding to different fault types of brakes is significantly different, thus a hydraulic disc brake fault diagnosis and judgment scheme based on vibration signal detection was proposed and validated in the paper. According to the composition and electric control principle of hydraulic brake, the vibration signal detection and brake pressure control strategies were established. The key hardware and isolation circuit of the detection system were designed, which can effectively improve the stability and anti-interference ability in the process of vibration data acquisition and transmission with SPI and CAN bus communication scheme. In order to eliminate noise interference in friction vibration signal and improve the accuracy of fault diagnosis with advantage, wavelet threshold denoising method was applied to brake disc vibration signal processing. The denoised signal can be obtained by inverting the selected wavelet coefficients to separate the useful components of the signal from the invalid noise. For the research on the correlation between fault types and vibration signal characteristics, a friction vibration test bench for hydraulic braking system was built to obtain and process the output signal from vibration sensor. The frequency spectrum response laws of vibration signals were compared and analyzed when the brake disc was normal and had surface defects, including microcracks, excessive wear and fatigue peeling. The external parameters such as brake pressure and spindle speed were keeping constant, thus eliminating the influence of working factors on vibration characteristics. In order to study the influence of brake pressure failure on friction vibration, the variation law of vibration signal is compared and analyzed under the condition of hydraulic valve leakage and pressure maintaining failure. The results show that the friction vibration signal can be used as an effective basis for judging the surface defects and brake pressure faults of brake discs. Under the condition of wavelet threshold denoising, accurate and effective vibration parameters can be obtained, which is of great significance to the safety and reliability of the braking system.
{"title":"Fault diagnosis and analysis of hydraulic brake based on friction vibration signal","authors":"Qiuhuan Ma, Yan Wang","doi":"10.21595/jve.2023.23078","DOIUrl":"https://doi.org/10.21595/jve.2023.23078","url":null,"abstract":"The friction vibration signal corresponding to different fault types of brakes is significantly different, thus a hydraulic disc brake fault diagnosis and judgment scheme based on vibration signal detection was proposed and validated in the paper. According to the composition and electric control principle of hydraulic brake, the vibration signal detection and brake pressure control strategies were established. The key hardware and isolation circuit of the detection system were designed, which can effectively improve the stability and anti-interference ability in the process of vibration data acquisition and transmission with SPI and CAN bus communication scheme. In order to eliminate noise interference in friction vibration signal and improve the accuracy of fault diagnosis with advantage, wavelet threshold denoising method was applied to brake disc vibration signal processing. The denoised signal can be obtained by inverting the selected wavelet coefficients to separate the useful components of the signal from the invalid noise. For the research on the correlation between fault types and vibration signal characteristics, a friction vibration test bench for hydraulic braking system was built to obtain and process the output signal from vibration sensor. The frequency spectrum response laws of vibration signals were compared and analyzed when the brake disc was normal and had surface defects, including microcracks, excessive wear and fatigue peeling. The external parameters such as brake pressure and spindle speed were keeping constant, thus eliminating the influence of working factors on vibration characteristics. In order to study the influence of brake pressure failure on friction vibration, the variation law of vibration signal is compared and analyzed under the condition of hydraulic valve leakage and pressure maintaining failure. The results show that the friction vibration signal can be used as an effective basis for judging the surface defects and brake pressure faults of brake discs. Under the condition of wavelet threshold denoising, accurate and effective vibration parameters can be obtained, which is of great significance to the safety and reliability of the braking system.","PeriodicalId":49956,"journal":{"name":"Journal of Vibroengineering","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41888375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Power reflux hydraulic transmission system (PRHTS), which is a recently introduced continuously variable transmission system, enables the improvement of fuel economy of construction vehicles. For investigating the nonlinear dynamic characteristics of PRHTS, its nonlinear dynamic model is established by merging the dynamic models of a planetary gear train and torque converter. A dynamical model of the planetary gear train reveals the parameters of mesh damping, time-varying mesh stiffness, and transmission error. The nonlinear dynamic equations of the PRHTS are solved using the fourth-order Runge-Kutta method. The dynamic orbits of the system are observed through bifurcation diagrams, which use the internal excitation frequency and meshing damping ratios, both of which are dimensionless, as control parameters. Numerical examples show the dynamic evolution mechanism involving one-period motion, multi-periodic motion, quasi-periodic motion, and chaotic motion. The onset of chaotic motion is identified from bifurcation diagrams, dynamic trajectories, phase plane diagram, and Poincaré maps of the PRHTS. The simulation results provide an understanding of the operating conditions under which undesirable dynamic motion occurs in PRHTS and serve as invaluable information for effective dynamic design of PRHTS.
{"title":"Nonlinear dynamic analysis of power reflux hydraulic transmission system","authors":"Huan Wang, Shuaishuai Ge, Dong Guo, Y. Jiang","doi":"10.21595/jve.2022.22376","DOIUrl":"https://doi.org/10.21595/jve.2022.22376","url":null,"abstract":"Power reflux hydraulic transmission system (PRHTS), which is a recently introduced continuously variable transmission system, enables the improvement of fuel economy of construction vehicles. For investigating the nonlinear dynamic characteristics of PRHTS, its nonlinear dynamic model is established by merging the dynamic models of a planetary gear train and torque converter. A dynamical model of the planetary gear train reveals the parameters of mesh damping, time-varying mesh stiffness, and transmission error. The nonlinear dynamic equations of the PRHTS are solved using the fourth-order Runge-Kutta method. The dynamic orbits of the system are observed through bifurcation diagrams, which use the internal excitation frequency and meshing damping ratios, both of which are dimensionless, as control parameters. Numerical examples show the dynamic evolution mechanism involving one-period motion, multi-periodic motion, quasi-periodic motion, and chaotic motion. The onset of chaotic motion is identified from bifurcation diagrams, dynamic trajectories, phase plane diagram, and Poincaré maps of the PRHTS. The simulation results provide an understanding of the operating conditions under which undesirable dynamic motion occurs in PRHTS and serve as invaluable information for effective dynamic design of PRHTS.","PeriodicalId":49956,"journal":{"name":"Journal of Vibroengineering","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49114610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Highway tunnels built in China in the early years of operation have different forms of diseases, which have a great impact and threat to the normal operation and safety of the tunnel. To ensure the safety and stability of the lining structure, this paper analyzes the mechanical behavior of the lining structure under the influence of the disease and reveals the evolution law of the lining crack disease for typical tunnel lining cracks. The results of the study show that only the circumferential and longitudinal stresses at the vault increase when cracks exist in the inner wall of the lining vault. The longitudinal cracks in the inner wall of the lining have the greatest influence on the lining stress state.
{"title":"Mechanical behavior of a highway tunnel under the influence of lining crack disease","authors":"Dongkui Zhao, Xiaojuan Quan, Huan Zhou, Wenchang Sun, Yiwen Huang, Nan Jiang","doi":"10.21595/jve.2023.22969","DOIUrl":"https://doi.org/10.21595/jve.2023.22969","url":null,"abstract":"Highway tunnels built in China in the early years of operation have different forms of diseases, which have a great impact and threat to the normal operation and safety of the tunnel. To ensure the safety and stability of the lining structure, this paper analyzes the mechanical behavior of the lining structure under the influence of the disease and reveals the evolution law of the lining crack disease for typical tunnel lining cracks. The results of the study show that only the circumferential and longitudinal stresses at the vault increase when cracks exist in the inner wall of the lining vault. The longitudinal cracks in the inner wall of the lining have the greatest influence on the lining stress state.","PeriodicalId":49956,"journal":{"name":"Journal of Vibroengineering","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45352483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tree Planting Machine (TPM) is subject to a Tree-Planting Robot (TPR) with desired tracking trajectory planning. In this topic, taking the TPR proposed as the analysis object, the positive and inverse solutions of the kinematics are analyzed to explore the optimal trajectory planning. An improved position/posture algorithm, based on the analytical solution of the inverse kinematics of the TPR, is proposed. The trajectory planning strategy for TPR in Cartesian coordinate system and Joint coordinate system is discussed, which is used for parabolic transition linear programming optimization, and the simulation model of TPR trajectory planning is constructed by MATLAB module. Numerical simulation results indicate that the deviation of the TPR trajectory from the expected value is significantly reduced. The proposed improved position/posture algorithm is verified by kinematic analysis, and the TPR followability and trajectory planning accuracy are greatly improved. Toward this goal, a variable trajectory planning can be effectively, and stability adjusted by pre-designed TPM system in the field of ecological tree planting.
{"title":"Kinematic analysis and trajectory planning for a tree planting robot in forest environment","authors":"Xigui Wang, Zhiqin Zhang, Xiangjie Meng","doi":"10.21595/jve.2023.23110","DOIUrl":"https://doi.org/10.21595/jve.2023.23110","url":null,"abstract":"Tree Planting Machine (TPM) is subject to a Tree-Planting Robot (TPR) with desired tracking trajectory planning. In this topic, taking the TPR proposed as the analysis object, the positive and inverse solutions of the kinematics are analyzed to explore the optimal trajectory planning. An improved position/posture algorithm, based on the analytical solution of the inverse kinematics of the TPR, is proposed. The trajectory planning strategy for TPR in Cartesian coordinate system and Joint coordinate system is discussed, which is used for parabolic transition linear programming optimization, and the simulation model of TPR trajectory planning is constructed by MATLAB module. Numerical simulation results indicate that the deviation of the TPR trajectory from the expected value is significantly reduced. The proposed improved position/posture algorithm is verified by kinematic analysis, and the TPR followability and trajectory planning accuracy are greatly improved. Toward this goal, a variable trajectory planning can be effectively, and stability adjusted by pre-designed TPM system in the field of ecological tree planting.","PeriodicalId":49956,"journal":{"name":"Journal of Vibroengineering","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45803342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhenqian Wang, Jida Wu, Zhaojun Kou, Yuanming Zhang, Chusheng Liu
The vibrating screen with statically indeterminate mesh beam structure (VSSIMBS) is a novel type of large vibrating screen, which is widely used in coal preparation plants due to its high strength and processing capacity. In this study, the VSSIMBS motion differential equations were obtained via on Lagrange equation, and the dynamic vibration system model was established. The eccentric block force conditions during the operation were analyzed, and the stable vibrating screen operational conditions were obtained. The electromechanical coupling simulation model of VSSIMBS was built in Simulink, allowing frequency control and vibration synchronization experiments. Experimental frequency control results have shown that when the output characteristics of both motors are either the same or similar, synchronous movement can be achieved. Regarding vibration synchronization, experiment results have shown that when two motors are in synchronous motion, and the power supply of one motor is cut off, they still can operate synchronously. Thus, the experimental results obtained in this study provide a theoretical reference for improving the motion stability of large vibrating screens.
{"title":"Dynamic characteristics analysis of a novel vibrating screen based on electromechanical coupling simulation","authors":"Zhenqian Wang, Jida Wu, Zhaojun Kou, Yuanming Zhang, Chusheng Liu","doi":"10.21595/jve.2023.22823","DOIUrl":"https://doi.org/10.21595/jve.2023.22823","url":null,"abstract":"The vibrating screen with statically indeterminate mesh beam structure (VSSIMBS) is a novel type of large vibrating screen, which is widely used in coal preparation plants due to its high strength and processing capacity. In this study, the VSSIMBS motion differential equations were obtained via on Lagrange equation, and the dynamic vibration system model was established. The eccentric block force conditions during the operation were analyzed, and the stable vibrating screen operational conditions were obtained. The electromechanical coupling simulation model of VSSIMBS was built in Simulink, allowing frequency control and vibration synchronization experiments. Experimental frequency control results have shown that when the output characteristics of both motors are either the same or similar, synchronous movement can be achieved. Regarding vibration synchronization, experiment results have shown that when two motors are in synchronous motion, and the power supply of one motor is cut off, they still can operate synchronously. Thus, the experimental results obtained in this study provide a theoretical reference for improving the motion stability of large vibrating screens.","PeriodicalId":49956,"journal":{"name":"Journal of Vibroengineering","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48574607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pan Fang, Kang Yang, Gao Li, Qunfang Feng, Shujie Ding
The lateral vibration of drill string causes well deviation and the collision between drill collar and sidewall, and severe lateral vibration even affects the drilling safety or reliability. In view of the problems above, the lateral vibration characteristics of drill string need to be analyzed. Therefore, a newly vibration-collision model of BHA (bottom hole assembly) with random collision characteristics is proposed in this paper. Firstly, the dynamic model of drill collar with double stabilizer is presented by utilizing the Lagrange equations. Secondly, the dynamic characteristics of drill collar in air and mud drilling is analyzed with different collision frequencies. Subsequently, the displacement and motion trajectory of drill collar under different structure parameters of BHA and mechanical parameters of system are investigated by numerical simulation. Finally, the influence of rotation speed of BHA and length of drill collar on lateral vibration of drill collar is discussed. The results indicate that the lateral vibration of drill collar in air drilling is more serious than that in mud drilling; and the higher the collision frequency, the more severe the lateral vibration. Improving rotation speed of BHA, length of drill collar and WOB (weight on bit) have promoting influence on lateral vibration of drill collar; however, increasing stabilizer diameter has suppressing influence on lateral vibration of drill collar. The research findings give reasonable guidance for structure design of BHA and selection of mechanical parameters of system.
{"title":"Vibration-collision mechanism of dual-stabilizer bottom hole assembly system in vertical wellbore trajectory","authors":"Pan Fang, Kang Yang, Gao Li, Qunfang Feng, Shujie Ding","doi":"10.21595/jve.2022.22813","DOIUrl":"https://doi.org/10.21595/jve.2022.22813","url":null,"abstract":"The lateral vibration of drill string causes well deviation and the collision between drill collar and sidewall, and severe lateral vibration even affects the drilling safety or reliability. In view of the problems above, the lateral vibration characteristics of drill string need to be analyzed. Therefore, a newly vibration-collision model of BHA (bottom hole assembly) with random collision characteristics is proposed in this paper. Firstly, the dynamic model of drill collar with double stabilizer is presented by utilizing the Lagrange equations. Secondly, the dynamic characteristics of drill collar in air and mud drilling is analyzed with different collision frequencies. Subsequently, the displacement and motion trajectory of drill collar under different structure parameters of BHA and mechanical parameters of system are investigated by numerical simulation. Finally, the influence of rotation speed of BHA and length of drill collar on lateral vibration of drill collar is discussed. The results indicate that the lateral vibration of drill collar in air drilling is more serious than that in mud drilling; and the higher the collision frequency, the more severe the lateral vibration. Improving rotation speed of BHA, length of drill collar and WOB (weight on bit) have promoting influence on lateral vibration of drill collar; however, increasing stabilizer diameter has suppressing influence on lateral vibration of drill collar. The research findings give reasonable guidance for structure design of BHA and selection of mechanical parameters of system.","PeriodicalId":49956,"journal":{"name":"Journal of Vibroengineering","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47511829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The music melody can be used to distinguish the genre style of music and can also be used for retrieving music works. This paper used a deep learning algorithm, the convolutional neural network (CNN), to extract the features of musical melodies and recognize genres. Three-tuple samples were used as training samples in the training process. Orthogonal experiments were conducted on the number of music segments and the type of activation function in the algorithm in the simulation experiments. The CNN algorithm was compared with support vector machine (SVM) and traditional CNN algorithms. The results showed that there were obvious differences in the pitch and melody curves of different genres of music; the recognition performance was best when the number of music segments was six and the activation function was relu; the CNN algorithm trained by three-tuple samples had better recognition accuracy and spent less recognition time.
{"title":"Extraction and recognition of music melody features using a deep neural network","authors":"Zhong‐Jiang Zhang","doi":"10.21595/jve.2023.23075","DOIUrl":"https://doi.org/10.21595/jve.2023.23075","url":null,"abstract":"The music melody can be used to distinguish the genre style of music and can also be used for retrieving music works. This paper used a deep learning algorithm, the convolutional neural network (CNN), to extract the features of musical melodies and recognize genres. Three-tuple samples were used as training samples in the training process. Orthogonal experiments were conducted on the number of music segments and the type of activation function in the algorithm in the simulation experiments. The CNN algorithm was compared with support vector machine (SVM) and traditional CNN algorithms. The results showed that there were obvious differences in the pitch and melody curves of different genres of music; the recognition performance was best when the number of music segments was six and the activation function was relu; the CNN algorithm trained by three-tuple samples had better recognition accuracy and spent less recognition time.","PeriodicalId":49956,"journal":{"name":"Journal of Vibroengineering","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49621262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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