Advances in Mechanical Engineering最新文献

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Modeling and analysis of transition-point disappearance in high-speed railway pantograph-catenary system 高速铁路受电弓-接触网系统过渡点消失建模与分析
4区 工程技术
Advances in Mechanical Engineering Pub Date : 2023-11-01 DOI: 10.1177/16878132231210083
Junqing Chen, Jidong Liu, Jinfa Guan, Feng Han, Jiqing Wu, Weirong Chen
{"title":"Modeling and analysis of transition-point disappearance in high-speed railway pantograph-catenary system","authors":"Junqing Chen, Jidong Liu, Jinfa Guan, Feng Han, Jiqing Wu, Weirong Chen","doi":"10.1177/16878132231210083","DOIUrl":"https://doi.org/10.1177/16878132231210083","url":null,"abstract":"During the operation of high-speed railway, the transition-point disappearance phenomenon, which is caused by the deformation of pantograph head, poses a safety threat to the pantograph-catenary system. In this study, the analytical model for transition-point disappearance analysis is presented. The instantaneous profile, as well as the deformation process of the pantograph head under different contact force values and positions or different pantograph-head parameters can be solved using the model. Curve equation, force analysis, coordinate axis rotation, and few other methods are adopted to achieve simplified modeling. The proposed modeling method and analysis conclusion provide theoretical support for the permissible contact force range calculation and pantograph-head parameters optimization to prevent transition-point disappearance. The effectiveness of the proposed model is verified using both finite element simulation and experimental measurements. Finally, a case analysis for the prevention of transition-point disappearance is conducted, using pantographs with the models CX-GI and DSA250 as examples.","PeriodicalId":49110,"journal":{"name":"Advances in Mechanical Engineering","volume":"24 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135765241","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
Identification method for unsteady friction of tool flank for high efficiency milling cutter 高效铣刀刀面非定常摩擦识别方法
4区 工程技术
Advances in Mechanical Engineering Pub Date : 2023-11-01 DOI: 10.1177/16878132231204571
Bin Jiang, Binxu Wang, Peiyi Zhao, Lili Fan, Fan Yang
{"title":"Identification method for unsteady friction of tool flank for high efficiency milling cutter","authors":"Bin Jiang, Binxu Wang, Peiyi Zhao, Lili Fan, Fan Yang","doi":"10.1177/16878132231204571","DOIUrl":"https://doi.org/10.1177/16878132231204571","url":null,"abstract":"Under the cutting loads of high efficiency and intermittent, the friction status between the tool flank and transition surface has time-varying characteristics, which directly affects friction and wear performance of the milling cutter. The dynamic distribution of instantaneous friction on tool flank under milling vibration needs to be revealed. In this work, the effect of milling vibration on instantaneous cutting contact relationship between milling cutter and workpiece was researched, a calculation method for the instantaneous friction velocity and friction energy consumption on tool flank was proposed. The variation of instantaneous friction between tool flank and transition surface under milling vibration was identified and evaluated by power spectral entropy and cross-correlation function. A method for identifying the unsteady friction of tool flank was proposed. The response analysis and experimental verification were conducted. The results showed that the frequency domain parameter distribution of friction energy consumption on tool flank had a strong correlation with the wear depth distribution, and was obviously sensitive to the milling parameters. The above models and methods could be used to reveal the influence of key milling process variables on unsteady friction and wear process of milling cutter’s multiple tool flank.","PeriodicalId":49110,"journal":{"name":"Advances in Mechanical Engineering","volume":"55 5-6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135614075","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
Magnetohydrodynamic hybrid nanofluid flow through moving thin needle considering variable viscosity and thermal conductivity 考虑变粘度和热导率的磁流体动力混合纳米流体在移动细针中的流动
4区 工程技术
Advances in Mechanical Engineering Pub Date : 2023-11-01 DOI: 10.1177/16878132231208272
Mohammad Ferdows, Sultana Jahan, Efstratios Tzirtzilakis, Shuyu Sun
{"title":"Magnetohydrodynamic hybrid nanofluid flow through moving thin needle considering variable viscosity and thermal conductivity","authors":"Mohammad Ferdows, Sultana Jahan, Efstratios Tzirtzilakis, Shuyu Sun","doi":"10.1177/16878132231208272","DOIUrl":"https://doi.org/10.1177/16878132231208272","url":null,"abstract":"In modern science and technology, industrial applications that deal with the problem of continuously moving thin needle, surrounded with fluid in sectors like hot rolling, crystal growing, heat extrusion, glass fiber drawing, etc., are rapidly increasing. Such processes involve high temperatures which may affect the fluid properties that is, viscosity and thermal conductivity. So, it’s crucial to understand temperature-dependent fluid properties. Focused on these assumptions, the main objective of the current research work is to investigate how temperature-dependent fluid properties might improve the heat transfer efficiency and performance evolution of hybrid nanofluid in the presence of transverse magnetic field over a moving thin needle. Variable Prandtl number is also introduced to observe flow fluctuation, the effect of adding nanoparticles, and enhancement in heat transmission. The results are obtained for different needle thicknesses, temperature-dependent viscosity, temperature-dependent thermal conductivity, and heat generation. Moreover, Fe 3 O 4 /Graphene nanoparticles are considered to be dispersed in water. The governing partial differential equations of flow and heat transfer are transformed into a system of coupled nonlinear ordinary differential equations using analysis of similarity conversion. Subsequently, the numerical solution of the problem is attained by employing the MAPLE software. The fourth-fifth-order Runge-Kutta-Fehlberg (RFK45) approach is used by default in this MAPLE program to address the numerical problem of boundary value. The velocity and temperature field are pictured for different values of the parameters as well as physical quantities of interest such as skin friction coefficient and rate of heat transfer are visually depicted in graphs and tables. It is found that fluid motion and energy transport are highly regulated by the variation of magnetic field strength. As the volume fraction of Fe 3 O 4 is increased, the heat generation, and thermal conductivity parameter vehemently enhance the temperature profile which leads to a rise in thermal boundary layer. A strong augmentation in the heat transfer rate has been found with the increment in the variable Prandtl number.","PeriodicalId":49110,"journal":{"name":"Advances in Mechanical Engineering","volume":"22 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135516822","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
Design and analysis of a passive knee assisted exoskeleton 被动式膝关节辅助外骨骼的设计与分析
4区 工程技术
Advances in Mechanical Engineering Pub Date : 2023-11-01 DOI: 10.1177/16878132231202578
Yawen Zhou, Xupeng Wang, Xinyao Tang, Xiaomin Ji, Zhu Gao
{"title":"Design and analysis of a passive knee assisted exoskeleton","authors":"Yawen Zhou, Xupeng Wang, Xinyao Tang, Xiaomin Ji, Zhu Gao","doi":"10.1177/16878132231202578","DOIUrl":"https://doi.org/10.1177/16878132231202578","url":null,"abstract":"In order to reduce the impact of knee injury and energy consumption during exercise, an unpowered exoskeleton was proposed based on the characteristics of ergonomics and human lower limb gait. The device is assisted by a double spring mechanism and worn parallel to the knee joint. The metabolic energy of the human body is reduced by compensating for the energy loss the lower limbs negative work. At the same time, the elastic energy storage element is simulated and analyzed in ANSYS software, and the corresponding relationship between the size of energy storage unit and strain energy is determined, so as to realize the parameter matching design and application of energy storage unit. Finally, the effectiveness of the exoskeleton is proved by analyzing EMG data and human knee torque data. The experimental results showing that the exoskeleton has a good assistant effect, and can achieve the purpose of daily walking assistance.","PeriodicalId":49110,"journal":{"name":"Advances in Mechanical Engineering","volume":"114 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135566095","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
Accurate time-frequency estimation in sαs noise via memory-dependent derivative 利用记忆相关导数对sαs噪声进行精确时频估计
4区 工程技术
Advances in Mechanical Engineering Pub Date : 2023-11-01 DOI: 10.1177/16878132231209883
Pan Huang, Jun Xiao, Weitao Sun, Meng Wang
{"title":"Accurate time-frequency estimation in sαs noise via memory-dependent derivative","authors":"Pan Huang, Jun Xiao, Weitao Sun, Meng Wang","doi":"10.1177/16878132231209883","DOIUrl":"https://doi.org/10.1177/16878132231209883","url":null,"abstract":"This letter presents a time-frequency estimation approach based on memory-dependent derivative to obtain accurate spectrograph interpolation information. The memory correlation derivative is the convolution of a time-varying signal with a dynamic weighting function over a past time period with respect to a common derivative. Considering the described method, discrete data from previous times can be derived to estimate the signal values at the current time and to reduce the effect of noise. Fourier transforms with different scales and delay transforms are used as kernel functions to obtain energy-concentrated time-frequency curves with higher resolution and without frequency leakage. Besides, the memory-dependent derivative with adjustable scale factor is used to overcome time-frequency grid mismatches. Furthermore, differing from the phase accumulation manner of conventional time-frequency estimation, ℓ 1 -norm suppresses the heavy-tailed effect from outliers, thus the robustness of estimator can be enhanced greatly. By suitably choices of scale factor, the estimator can be tuned to exhibit high resolution in targeted regions of the time-frequency spectrum.","PeriodicalId":49110,"journal":{"name":"Advances in Mechanical Engineering","volume":"19 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135714964","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 extraction method of new type of train control system operation scenario elements in special environments 特殊环境下新型列控系统运行场景要素提取方法研究
4区 工程技术
Advances in Mechanical Engineering Pub Date : 2023-10-01 DOI: 10.1177/16878132231203811
Penghui Huang, Lei Yuan, Guodong Wei
{"title":"Research on extraction method of new type of train control system operation scenario elements in special environments","authors":"Penghui Huang, Lei Yuan, Guodong Wei","doi":"10.1177/16878132231203811","DOIUrl":"https://doi.org/10.1177/16878132231203811","url":null,"abstract":"At present, the construction of high-speed railway in the western region has become one of the key points in China. However, the existing train control systems do not adapt to the environment. So a new type of train control system (TCS-NT) is proposed. However, for TCS-NT, the definition and content of its operating scenarios are not clear, and the construction of operating scenarios is mostly involves subjective analysis. It faces problems such as a lack of a comprehensive operating environment analysis method, a method for selecting scenario elements for varying test requirements, and inexplicable design choices. In this paper, the Operational Design Domain (ODD) and a key element extraction method for simulation scenarios are proposed to analyze the operational environment of the TCS-NT. Using this method, the impact of each scenario element on the sub-functions is sequentially analyzed in the tracking operation scenario of the TCS-NT. According to the influence on each sub-function, a mapping equation is constructed for the three-dimensional plane comprising element, structure, and function, and scenario elements are extracted using the discriminant matrix. In this paper, the method is used to analyze the operation scenario in the train tracking scene, and the feasibility of the method is verified.","PeriodicalId":49110,"journal":{"name":"Advances in Mechanical Engineering","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135605972","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 optimization model for low-carbon product family design considering component reliability and warranty period 考虑部件可靠性和质保期的低碳产品族设计优化模型
4区 工程技术
Advances in Mechanical Engineering Pub Date : 2023-10-01 DOI: 10.1177/16878132231204806
Qi Wang, Peipei Qi, Shipei Li
{"title":"An optimization model for low-carbon product family design considering component reliability and warranty period","authors":"Qi Wang, Peipei Qi, Shipei Li","doi":"10.1177/16878132231204806","DOIUrl":"https://doi.org/10.1177/16878132231204806","url":null,"abstract":"Due to the considerations of the carbon footprint of the product, low-carbon product family design has attracted more and more attention. The existing low-carbon product family design methods do not adequately take into account the component reliability and warranty period. At present, providing warranty for key components of the product is an important marketing tool, and it is widely adopted by manufacturers. In fact, when component reliability and warranty period are considered in a low-carbon product family design, they affect not only the profit of the product family, but also the GHG emission. To this end, the article proposes an optimization model that optimizes product family design, supplier selection and component warranty period in parallel. The objective of the model is to maximize the profit of the product family and minimize GHG emission while satisfying various constraints. The developed model is solved using a genetic algorithm. The method’s effectiveness is verified through a case study, and a sensitivity analysis is performed. The method can assist manufacturers in simultaneously determining the product family configuration, supplier selection and the component warranty period based on their goal preferences.","PeriodicalId":49110,"journal":{"name":"Advances in Mechanical Engineering","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135708011","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
Insight into stagnant point flow of Eyring-Powell hybrid nanofluid comprising on enlarged version of Yamada-Ota and Xue model 扩大版Yamada-Ota - Xue模型对Eyring-Powell混合纳米流体滞点流动的认识
4区 工程技术
Advances in Mechanical Engineering Pub Date : 2023-10-01 DOI: 10.1177/16878132231206922
Farhan Ali, Syed Sohaib Zafar, Soofia Iftikhar, Muhammad Faizan Ahmad, Anwar Saeed
{"title":"Insight into stagnant point flow of Eyring-Powell hybrid nanofluid comprising on enlarged version of Yamada-Ota and Xue model","authors":"Farhan Ali, Syed Sohaib Zafar, Soofia Iftikhar, Muhammad Faizan Ahmad, Anwar Saeed","doi":"10.1177/16878132231206922","DOIUrl":"https://doi.org/10.1177/16878132231206922","url":null,"abstract":"This paper shows the stagnant point flow of Powell-Eyring hybrid nanofluids due to a stretching sheet. The Xue and Yamada-Ota based on hybrid nanoliquid have been subjected to a comparison study that has been scrutinized. The suspension of two nanoparticles [Formula: see text] and [Formula: see text] with base fluid Ethylene glycol ([Formula: see text]) is studied through hybrid nanoliquid. With the implementation of the noteworthy suitable alteration, the system of equations in terms of ODEs is established. The bvp4c technique is then applied to obtain the numerical solution of reduced ODEs. The significance of physical quantities over thermal, velocity, force friction, and heat transport are elaborated in tabular form and also in graphical form. During this analysis, the Xue model produced less heat transport as compared to the Yamada-Ota hybrid nanofluid. The result shows that the Xue model produces less heat gradient equated to the Yamada-Ota model. The velocity profile is enhanced and the thermal profile has decayed with the larger value of the fluid parameter.","PeriodicalId":49110,"journal":{"name":"Advances in Mechanical Engineering","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135963774","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
The impact of curved-tip propeller geometry on hovering drone performance for air quality monitoring 曲线尖端螺旋桨几何形状对悬停无人机空气质量监测性能的影响
4区 工程技术
Advances in Mechanical Engineering Pub Date : 2023-10-01 DOI: 10.1177/16878132231206330
Mohamed Abdessamia Chakchouk, Abdelkhalak El Hami, Pierre Richard Dahoo, Azzedine Lakhlifi, Wajih Gafsi, Mohamed Haddar
{"title":"The impact of curved-tip propeller geometry on hovering drone performance for air quality monitoring","authors":"Mohamed Abdessamia Chakchouk, Abdelkhalak El Hami, Pierre Richard Dahoo, Azzedine Lakhlifi, Wajih Gafsi, Mohamed Haddar","doi":"10.1177/16878132231206330","DOIUrl":"https://doi.org/10.1177/16878132231206330","url":null,"abstract":"The success or failure of a drone mission depend on several elements, including the drone’s mass and payload, the surrounding environment, the battery’s state, and the propulsion system’s performance. Several studies have been undertaken addressing the propeller performance of this final component, particularly for fixed-wing or quad copter drones with ducted propellers. However, the shape of propeller blades used on tiny civil drones has not drawn as much attention. In this research work, the performance characteristics of a 10 × 4.7-inch curved tip propeller were explored, with the Advanced Precision Composite drone propeller serving as a design reference. This study seeks an alternative to ducted propellers when mass or size limitations prevent their use. The Computational Fluid Dynamics model was confirmed by comparing simulation results to the experimental propeller data source established by the University of Illinois at Urbana-Champaign, starting with a standard type propeller and using thrust coefficient as the key performance indicator. Moreover, the data analysis for the bended tip propeller replicating the well-established model, revealed the benefits as well as the drawbacks of such propellers on the mission profile and the battery lifespan of a quad copter Unmanned Air Vehicle.","PeriodicalId":49110,"journal":{"name":"Advances in Mechanical Engineering","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136059545","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
Investigation of cavitation phenomenon with different fuel temperatures in diesel nozzles 不同燃油温度下柴油机喷嘴内空化现象的研究
4区 工程技术
Advances in Mechanical Engineering Pub Date : 2023-10-01 DOI: 10.1177/16878132231202867
Tianyi Cao, Zhixia He, Jianquan Wang
{"title":"Investigation of cavitation phenomenon with different fuel temperatures in diesel nozzles","authors":"Tianyi Cao, Zhixia He, Jianquan Wang","doi":"10.1177/16878132231202867","DOIUrl":"https://doi.org/10.1177/16878132231202867","url":null,"abstract":"Two-phase cavitating flow in the diesel nozzle has been widely concerned by researchers for a long time. Most of the attention has been paid to irregular geometry-induced cavitation, while the research on string cavitation induced by vortex is relatively less. The two cavitating patterns often occur simultaneously in the nozzle, which are still not understandable for their interaction characteristics. In this paper, it is analyzed that the characteristics of string cavitation and geometry-induced cavitation in the transparent nozzle based on the visual scale-up test bench. In the study of hole-to-hole string cavitation, it is found that when needle lifts elevate, geometry-induced cavitation and hole-to-hole string cavitation are observed all together under the same working condition. The development and stability of hole-to-hole string cavitation are further improved with the increase of fuel temperature. The geometry-induced cavitation and string cavitation interact with each other, that is, geometry-induced cavitation at the nozzle inlet interrupts the hole-to-hole string cavitation inception. The tail of hole-to-hole string cavitation is disturbed by cloud cavitation shedding after its developing into the nozzle hole, leading to fracture in serious cases. At high temperatures, there is a periodic transformation between the needle-originated string cavitation and hole-to-hole string cavitation.","PeriodicalId":49110,"journal":{"name":"Advances in Mechanical Engineering","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136093652","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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