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Study on Mechanical Behavior and Deformation Law of Expansion Pro-cess of Expansion Screen Base Pipe 膨胀筛基管膨胀过程力学行为及变形规律研究
4区 工程技术
Mechanika Pub Date : 2023-10-18 DOI: 10.5755/j02.mech.33414
Pu LIU, Zhengqiang TANG, Ning DAI, Quanlin XIAO, Zhiping WANG, Chenlong WANG
{"title":"Study on Mechanical Behavior and Deformation Law of Expansion Pro-cess of Expansion Screen Base Pipe","authors":"Pu LIU, Zhengqiang TANG, Ning DAI, Quanlin XIAO, Zhiping WANG, Chenlong WANG","doi":"10.5755/j02.mech.33414","DOIUrl":"https://doi.org/10.5755/j02.mech.33414","url":null,"abstract":"The expansion process of the base pipe of the expanded screen pipe includes large displacement elastic-plastic deformation problems such as geometric nonlinearity, material nonlinearity and contact nonlinearity. In this paper, based on the elastic-plastic deformation mechanism of the base pipe of expanded screen pipe, finite element equations are established and numerical simulation is used to construct a finite element simulation model to study the mechanical behavior and deformation law of Φ203.2 mm base pipe of the expanded screen pipe expansion process. The results show that the expansion rate has no effect on the increase of wall thickness, and the decrease is proportional to the expansion rate. The greater the expansion rate, the greater the residual stress at both ends of the slot.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135885031","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
Transfemoral Prostheses: Importance of Proper Fitting and Materials for Socket 3D-Printing 经股假体:正确的配件和材料对3d打印窝的重要性
4区 工程技术
Mechanika Pub Date : 2023-10-18 DOI: 10.5755/j02.mech.33957
Donatas DAUBLYS, Aurelijus DOMEIKA, Birutė SINKUTĖ
{"title":"Transfemoral Prostheses: Importance of Proper Fitting and Materials for Socket 3D-Printing","authors":"Donatas DAUBLYS, Aurelijus DOMEIKA, Birutė SINKUTĖ","doi":"10.5755/j02.mech.33957","DOIUrl":"https://doi.org/10.5755/j02.mech.33957","url":null,"abstract":"Lower limb prostheses can replace missing parts of the body and improve a patient's quality of life. The individual design and manufacture of a prosthesis is particularly beneficial for the wearer. The 3D printing technique can be used to make prosthesis sockets from recycled polyamide powder (PA2200), but the mechanical properties of these printed materials have not been studied in detail. Tensile and bending tests were performed, and the results obtained did not show statistically significant differences between these materials. An improperly fitted prosthesis affects the biomechanics of gait. Posture and gait analysis of a person wearing a prosthesis was performed using the “Qualisys”, \"AMTI\" force plates, and “Zebris” systems, and the results showed differences between the prosthetic and the healthy leg.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135885161","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
Zero Point Compensation Control of the Proportional Valve with Negative Overlap 负重叠比例阀的零点补偿控制
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-08-09 DOI: 10.5755/j02.mech.29715
Le Zeng, Hongzhang Li, J. Tan, Jun Yang
{"title":"Zero Point Compensation Control of the Proportional Valve with Negative Overlap","authors":"Le Zeng, Hongzhang Li, J. Tan, Jun Yang","doi":"10.5755/j02.mech.29715","DOIUrl":"https://doi.org/10.5755/j02.mech.29715","url":null,"abstract":"In order to improve the performance of the negative overlapped valve controlled asymmetrical cylinder system, a theoretical zero point model of the valve with symmetric and unequal negative overlap was established. The simulation results showed that the zero point of the system will shift as the load changes, and the error of the theoretical zero point is relatively larger in some certain pressure states. In order to find the zero point quickly and steadily and improve the positioning accuracy of the system, a zero point compensation controller based on theoretical zero point plus error integral control was designed. Compared the pure P controller with the compound control of P controller and zero point compensation controller, the control accuracy of the system has been greatly improved under transient load and sinusoidal load interference.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47926962","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
Lubrication analysis of hydrodynamic-static hybrid bearing with deep-shallow chambers considering thermal conduction 考虑热传导的深浅腔动静压混合轴承润滑分析
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-08-09 DOI: 10.5755/j02.mech.33196
Qianwen Huang, Zeyu Zhao, Huai-Zhen Liu
{"title":"Lubrication analysis of hydrodynamic-static hybrid bearing with deep-shallow chambers considering thermal conduction","authors":"Qianwen Huang, Zeyu Zhao, Huai-Zhen Liu","doi":"10.5755/j02.mech.33196","DOIUrl":"https://doi.org/10.5755/j02.mech.33196","url":null,"abstract":"The oil film separates the shaft-bearing system to reduce the frictional force of contact surfaces with large temperature variations owing to thermal conduction. Multiple impact factors seriously affected the lubrication behavior of the bearing during actual working process. An applicable model regarding the lubrication analysis of a hydrodynamic-static hybrid bearing with deep-shallow chambers is proposed and validated with published literature. The lubrication behavior includes film pressure, load capacity, bearing stiffness and flow rate is numerically calculated with centered finite difference method by solving the Reynolds equation. The influence of film thickness and working temperature are considered, over a range of eccentricity ratio. Moreover, the temperature variation caused by thermal conduction is analyzed in details. To investigate the influence of thermal conduction on the lubrication behavior, the results show that the load capacity, bearing stiffness, friction power, and flow power significantly decline with the consideration of thermal conduction. This study proposes an accurate model that is helpful for the design of hydrodynamic-static hybrid bearings with deep-shallow chambers under low rotational speed, heavy load, and high temperature conditions.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43245570","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
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":null,"pages":null},"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":null,"pages":null},"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
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":null,"pages":null},"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
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":null,"pages":null},"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
An Energy-Based Anti-Fatigue Optimization Design Method of Welded Rear Axle Housing in a Mining Dump Truck 矿用自卸车焊接后桥壳基于能量的抗疲劳优化设计方法
IF 0.7 4区 工程技术
Mechanika Pub Date : 2023-08-09 DOI: 10.5755/j02.mech.32371
Chen Mi, Yongqiang Li, Chen Zhang, Dong Zhang, Xianghuan Liu, Xiaolan Hu, Dejun Zhang
{"title":"An Energy-Based Anti-Fatigue Optimization Design Method of Welded Rear Axle Housing in a Mining Dump Truck","authors":"Chen Mi, Yongqiang Li, Chen Zhang, Dong Zhang, Xianghuan Liu, Xiaolan Hu, Dejun Zhang","doi":"10.5755/j02.mech.32371","DOIUrl":"https://doi.org/10.5755/j02.mech.32371","url":null,"abstract":"In order to improve the life expectancy of the rear axle housing in a mining dump truck, an energy-based anti-fatigue optimization design method was presented in this paper. The finite element model of rear axle housing was constructed and testified by the experimental data. The load history was obtained through multi-body dynamics analysis, and the multi-load step nonlinear finite element analysis was carried out to obtain the stress-strain response under different working conditions. The strain energy density method was used to evaluate the fatigue life of rear axle housing, and the results showed that its fatigue endurance was insufficient. Then, the lifetime of the most dangerous point was taken as the optimization objective, and the different plate thickness was considered as the design variables. The approximate model was constructed based on the response surface method, and the anti-fatigue optimization design was finally conducted on the bearing structure through the multi-island genetic algorithm. The minimum fatigue life of optimized rear axle housing was doubled.","PeriodicalId":54741,"journal":{"name":"Mechanika","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43395818","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":null,"pages":null},"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
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