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Cluster-based Nonuniform Transformation Field Analysis of Gra-phene nanocomposites Graphene纳米复合材料的团簇非均匀变换场分析
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-08-09 DOI: 10.5755/j02.mech.33191
Yinan Jiang, Juanjuan Chen, L. Liang, Yangjian Xu, X. Ju
{"title":"Cluster-based Nonuniform Transformation Field Analysis of Gra-phene nanocomposites","authors":"Yinan Jiang, Juanjuan Chen, L. Liang, Yangjian Xu, X. Ju","doi":"10.5755/j02.mech.33191","DOIUrl":"https://doi.org/10.5755/j02.mech.33191","url":null,"abstract":"        Graphene nanocomposites have attracted much attention in materials science due to their superior me-chanical properties. It is difficult for conventional mul-tiscale methods to provide substantial assistance to the research of such materials due to their huge computa-tional costs. Nonuniform transformation field analysis is a very effective reduced order homogenization meth-od for elastoplastic multiscale analysis. However, the reduced order model derived from this method has the shortcoming of low universality and high application threshold. Therefore, an improved reduced order model is proposed by combining the nonuniform transfor-mation field analysis with the k-means clustering algo-rithm. One can embed the required microscopic consti-tutive model into the reduced order homogenization framework without the need to derive a new reduced order model. Based on the cluster-based nonuniform transformation field analysis, the influence of the mi-croscopic plastic strain field evolution on the macro-scopic response of the material under consideration is revealed, while the mechanical properties of graphene nanocomposites are predicted. The numerical results show that the new reduced order model can accurately predict the macroscopic mechanical properties of com-posite materials, and its acceleration rate compared to the traditional finite element computations reaches103-104 . \u0000Keywords:graphene nanocomposites; reduced order model; multiscale methods; clustering; nonuniform transfomation field analysis","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49670219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Novel Meshing Stiffness Model for Spur Gear Pairs considering the Temperature Effect 考虑温度效应的正齿轮副啮合刚度模型
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-08-09 DOI: 10.5755/j02.mech.33776
Y. He, Haibo Yang
{"title":"Novel Meshing Stiffness Model for Spur Gear Pairs considering the Temperature Effect","authors":"Y. He, Haibo Yang","doi":"10.5755/j02.mech.33776","DOIUrl":"https://doi.org/10.5755/j02.mech.33776","url":null,"abstract":"This work studied the effect of temperature on gear stiffness in the full temperature range which contained thermal expansion and cold shrinkage. Considering the temperature effect, a meshing stiffness model for spur gear pairs in the full temperature range was established based on the conservation of energy. The general calculation formula for the gear pair’s temperature meshing stiffness in the full temperature range was derived. The influence of addendum modification and gear temperature distribution on gear stiffness was studied. Thereafter, the proposed model was verified experimentally. The results revealed that the temperature stiffness was smaller than the standard stiffness of the gears in the full temperature range. When the temperature of the gears increased from an initial temperature, which was lower than the standard temperature, the temperature stiffness of the gear first increased and then decreased. Moreover, the obtained results could provide theoretical support for an accurate dynamic analysis of gear transmission systems in the full temperature range.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47732638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A Battery-free Breathing monitoring System for post-COVID education 用于新冠肺炎后教育的无电池呼吸监测系统
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-08-09 DOI: 10.5755/j02.mech.33435
Jun Wu, Zhifang Fan
{"title":"A Battery-free Breathing monitoring System for post-COVID education","authors":"Jun Wu, Zhifang Fan","doi":"10.5755/j02.mech.33435","DOIUrl":"https://doi.org/10.5755/j02.mech.33435","url":null,"abstract":"Embedded systems have more and more designs and applications in wearable health monitoring and the Internet of Things (IoT) recently. In this work, a battery-free human breathing monitoring system based on soft polyvinylidene fluoride (PVDF) piezoelectric thin film for pressure sensing and solid lead zirconate titanate (PZT) pads for powering energy harvest is designed and fabricated. Proper material and structure are chosen by the mechanical analysis to fabricate the systems. Then the device is used to measure the real breathing signal while studying (the memory test is used to represent the study procedure). The breathing frequency and intensity data are extracted and used in correction analysis with the testing score. And the results show that peaceful, slow, and deep breathing will have a positive influence on the testing score. This study opens the mind to combine the engineering designed device with education research, showing the broad application of mechanical and electronic systems.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49436055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Early Bearing Fault Detection Using EEMD and Three-Sigma Rule Denoising Method 基于EEMD和三σ规则去噪的轴承早期故障检测方法
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-08-09 DOI: 10.5755/j02.mech.32770
Yasser Damine, N. Bessous, A. C. Megherbi, S. Sbaa
{"title":"Early Bearing Fault Detection Using EEMD and Three-Sigma Rule Denoising Method","authors":"Yasser Damine, N. Bessous, A. C. Megherbi, S. Sbaa","doi":"10.5755/j02.mech.32770","DOIUrl":"https://doi.org/10.5755/j02.mech.32770","url":null,"abstract":"Rotating electrical machines have several physical phenomena. Vibration is one of the important phenomena in the operation of rotating electrical machines. In addition, the vibration signal is considered an important source to have good information on the state of rotating electrical machinery. But this signal is rich in noise, especially under the presence of the bearing fault. This paper proposes a bearing fault diagnosis method based on EEMD and a denoising method based on three-sigma rule. In the first step, the EEMD decomposed the vibration signal into several components called Intrinsic Mode Functions (IMFs). After the calculation of the kurtosis of each IMF component, the signal is reconstructed by choosing components with higher values. To enhance periodic impulses, the three-sigma rule de-noising is applied to the reconstructed signal. As a final step, the envelope spectrum is used to determine the fault characteristic frequency. As a result of testing the bearing with inner race fault and the bearing with outer race, it was verified that the proposed approach suppressed noise effectively and extracted rich fault information from the vibration signals of bearings compared to the EEMD.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46274768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Tuning of Mixing Zone Parameters in a Dynamic Mixer and Performance Comparison with Screw-based Mixers 动态混合器混合区参数的调整及与螺旋混合器的性能比较
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-08-09 DOI: 10.5755/j02.mech.33213
Jiagang Sun, Jiankang Wang, Yiwen Zheng, Zhijun Li
{"title":"Tuning of Mixing Zone Parameters in a Dynamic Mixer and Performance Comparison with Screw-based Mixers","authors":"Jiagang Sun, Jiankang Wang, Yiwen Zheng, Zhijun Li","doi":"10.5755/j02.mech.33213","DOIUrl":"https://doi.org/10.5755/j02.mech.33213","url":null,"abstract":"A new dynamic mixer has been designed for the mixing of two incompatible polymer melts. Three main design parameters (number of circles of holes (N), number of holes (M) per circle, and diameter of the holes (d3)) for the mixing zone of the dynamic mixer were selected to study their influences on the pressure drop (Δp) and the segregation scale (S) using Orthogonal tests. The influences of flow rate and rotational speed were also investigated. In addition, the mixing effect was compared with that of screw and slotted-screw mixers. The results showed that the most significant factor influencing S and S∙Δp is N. Both Δp and S increased with increasing flow rate, and decreased with increasing rotational speed. Compared to the screw and slotted-screw mixers, the dynamic mixer had a better mixing effect and shorter length.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43779974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Study on the Influence of Synthesized Nano Ferrite Powder and Micron Ferrite Powder on Damping of a Single Degree of Freedom System 合成纳米铁氧体粉末和微米铁氧体粉末对单自由度系统阻尼影响的研究
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-08-09 DOI: 10.5755/j02.mech.32055
Easu Dakshnamoorthy, Siddharthan Arjunan, Amrutha Radhakrishnan, A. Gopal
{"title":"Study on the Influence of Synthesized Nano Ferrite Powder and Micron Ferrite Powder on Damping of a Single Degree of Freedom System","authors":"Easu Dakshnamoorthy, Siddharthan Arjunan, Amrutha Radhakrishnan, A. Gopal","doi":"10.5755/j02.mech.32055","DOIUrl":"https://doi.org/10.5755/j02.mech.32055","url":null,"abstract":"Magneto Rheological Fluid (MRF) damper has been opted as a promising semi active element of advanced suspension system. This work focuses on the damping nature of magnetorheological fluid under the influence of a magnetic field strength, size and shape of the of the iron oxide particles. A reduced scale single degree of freedom quarter car model with two stage magnetorheological damper, viscosity measurement setup, synthesized and commercially available Fe2O3 powders are used for the experimental study. An air cooled electro-dynamic shaker, Data acquisition system, accelerometers and the Lab view software acquires and analyzes the response of the quarter car model. X-ray Diffraction and Scanning electron microscopy characterize the morphology of iron oxide particles. The vertical acceleration, the displacement, the transmissibility ratio and the damping characteristics are analyzed based on the response of the top plate at different frequencies of base excitation. The results show that the magnetorheological fluid made with nano iron oxide powder has better damping characteristics than that of micron sized iron oxide powder","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43365981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Position Decoupling Control of Rigid Rotor of Active Magnetic Bearing 主动磁轴承刚性转子位置解耦控制
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-08-09 DOI: 10.5755/j02.mech.31642
Binglin Li, L. Zeng
{"title":"Position Decoupling Control of Rigid Rotor of Active Magnetic Bearing","authors":"Binglin Li, L. Zeng","doi":"10.5755/j02.mech.31642","DOIUrl":"https://doi.org/10.5755/j02.mech.31642","url":null,"abstract":"The magnetic bearing rotor system has the problem of positional coupling in the direction of the radial degrees of freedom. This paper proposes a linear output feedback method which decouples the multi-variable coupling system into four single-degree-of-freedom second-order integral subsystems. Firstly, a five-degree-of-freedom(5-DOF) mathematical model of active magnetic bearing rotor is derived. Then, a sliding mode variable structure controller is designed for the decoupled subsystems and the stability of system is guaranteed by the Lyapunov stability theory. The results of computer simulation show that the design controller of sliding mode variable structure controller can more effectively enhance the magnetic bearing rotor performance stability compared with the conventional PD controller, fuzzy PD controller, no matter in the position respond control and anti-disturbance control. Moreover, the sliding mode variable structure controller make the system have better tracking performance.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43204579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Research on Pump Speed Control System Based on Fuzzy PID 基于模糊PID的水泵调速系统研究
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-06-17 DOI: 10.5755/j02.mech.32721
Yin Luo, Tao Jin, Xiao Li, Xuechong Qin, Yuejiang Han
{"title":"Research on Pump Speed Control System Based on Fuzzy PID","authors":"Yin Luo, Tao Jin, Xiao Li, Xuechong Qin, Yuejiang Han","doi":"10.5755/j02.mech.32721","DOIUrl":"https://doi.org/10.5755/j02.mech.32721","url":null,"abstract":"In this paper, based on MATLAB/simulink, the PID vector frequency conversion control of permanent magnet synchronous motor has better drive control performance in the multi-stage centrifugal pump speed control system. The electric-hydraulic coupling system of centrifugal pump has a good evaluation and research function. In view of the low efficiency of the traditional PID control method and the poor adaptability to the change of working environment, a vector control method of permanent magnet synchronous motor based on adaptive and self-adjusting fuzzy control principle is proposed for the speed regulation system of water pump. The simulation results show that the PMSM system controlled by the fuzzy PID controller is superior to the traditional PID control, and has better disturbance resistance, dynamic and steady performance.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48459668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Logistics Pure Electric Vehicle Routing Based on GA-PSO Algorithm 基于GA-PSO算法的物流纯电动汽车路径选择
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-06-17 DOI: 10.5755/j02.mech.31954
M. Wang, Qiyue Xie
{"title":"Logistics Pure Electric Vehicle Routing Based on GA-PSO Algorithm","authors":"M. Wang, Qiyue Xie","doi":"10.5755/j02.mech.31954","DOIUrl":"https://doi.org/10.5755/j02.mech.31954","url":null,"abstract":" Abstract:Based on current energy storage technologies such as batteries and fuel cells, the inherent battery capacity of electric vehicles puts constraints on their driving range and requires charging in the process of completing driving tasks. In this paper, with the current practical application in logistics industry as the background, from electric vehicle charging scheduling and path planning, a hybrid algorithm combining genetic-particle swarm algorithm is proposed to plan the best driving route for a group of electric logistics vehicles with vehicle load, vehicle battery life, charging facility location and customer time window as constraints and the total cost as the objective function. Based on the single distribution center, a more complex multi-distribution center electric vehicle path planning problem is considered. In this paper, multiple sets of Solomon VRPTW data sets are selected to test the prepared algorithm, and the results show that the algorithm can effectively plan the best distribution scheme.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46850397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Influence of Geometrical Shape on the Lubrication Performance of Partially Micro-Grooved Gas-Lubricated Parallel Slider Bearings 几何形状对部分微槽气体润滑平行滑块轴承润滑性能的影响
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-06-17 DOI: 10.5755/j02.mech.32384
Fuxi Liu, Chunjie Yang, Shanwu Xu, Kang Xie, Dunzhao Xie, Binhui Han, Zhanlong Li
{"title":"Influence of Geometrical Shape on the Lubrication Performance of Partially Micro-Grooved Gas-Lubricated Parallel Slider Bearings","authors":"Fuxi Liu, Chunjie Yang, Shanwu Xu, Kang Xie, Dunzhao Xie, Binhui Han, Zhanlong Li","doi":"10.5755/j02.mech.32384","DOIUrl":"https://doi.org/10.5755/j02.mech.32384","url":null,"abstract":"The influence of grooving parameters and micro-groove cross-section shape on the lubrication performance of partially micro-grooved gas-lubricated parallel slider bearings is investigated in the present study. The solution procedure for the multi-grid finite element method is that the algebraic equations formed by the finite element method are in turn smoothed by the interpolation from the coarse grid to the fine grid and the restriction from the fine grid to the coarse grid. By adopting the multi-grid finite element method, the pressure distribution of partially micro-grooved gas-lubricated parallel slider bearings is obtained. The grooving parameters are optimized to obtain the maximum average pressure for different micro-groove cross-section shapes. The results show that the orientation angle of the micro-grooves, depth of the micro-grooves, width of the micro-grooves, area density of the micro-grooves, micro-grooved fraction, and cross-section shape of the micro-grooves have an important influence on the hydrodynamic pressure of partially micro-grooved gas-lubricated parallel slider bearings. The results of this study demonstrate that the lubrication performance of partially micro-grooved gas-lubricated parallel slider bearings can be obviously enhanced by adopting the appropriate grooving parameters and micro-groove cross-shape. The results of this study is beneficial for the design of partially micro-grooved gas-lubricated parallel slider bearings.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43779079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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